Saturday, October 23, 2010
Go to Health: Can Beet Juice Beat High Blood Pressure?
About one in three US adults has high blood pressure; this is a big problem because blood pressure elevation is a leading contributor to heart attacks and stroke. Amrita Ahluwalia, a professor of vascular biology at Queen Mary’s William Harvey Research Institute in England, has found that blood pressure can be lowered effectively by natural means – drinking 8 ounces of beet juice daily. The nitrate (NO-3) found in beet juice is converted in saliva, by bacteria on the tongue, to nitrite (NO-2); in the acidic environment of the stomach. Nitrite is then converted by various enzymes to nitric oxide (NO). Nitric oxide is a gas that diffuses freely across cell membranes, and signals the smooth muscle surrounding blood vessels to relax, thus resulting in lower blood pressure and increased blood flow. NO also prevents blood platelets and white blood cells from sticking to blood vessel walls, thereby helping to lessen a buildup of plaque. Viagra and related drugs stimulate erections primarily by providing increased NO to blood vessels in the penis. Nitroglycerin, used to decrease the pain of angina, also works by releasing NO to dilate blood vessels in the heart muscle.
Professor Ahluwalia and her team found that in healthy volunteers, blood pressure was reduced within an hour of drinking about 8 ounces of beet juice, with a peak at 3-4 hours later, and some degree of reduction for 24 hours. Since nitric oxide is also formed after eating green leafy vegetables, the mechanism of action of the DASH diet may be similarly explained. The DASH diet – Dietary Approach to Stop Hypertension – emphasizes eating large amounts of vegetables and fruits, along with some low-fat dairy products and little added salt. Look at dashdiet.org for a good discussion of this effective plan.
A recent study of beet juice showed that athletes given beet juice could complete a cycling test for a significantly longer time than when given a placebo. They were able to use oxygen more efficiently during endurance exercise. This finding may also help people with poor fitness who need to increase their exercise tolerance.
Beet juice can have side effects, so it is important to discuss these with you doctor before starting to use it regularly. This is especially true for people taking medication to lower blood pressure. Drinking beet juice can cause dizziness, perhaps because of the drop in blood pressure. Beets can cause red urine and feces, which is a harmless side effect but could make the uninformed think they are bleeding internally. Occasionally people drinking beet juice have a temporary paralysis of the vocal cords, making it hard to talk for a period of time. This can be alarming – and should signal the user to stop the beet juice regimen. Some people are allergic to beets – there is a correlation here with allergy to latex. Beet juice should not be given to children.
If you don’t have your own juicer, it may be expensive to buy beet juice. Biotta sells organic beet juice (17 ounce bottle) on line for $5 plus shipping: With enough demand, your local natural foods store might stock the juice. If this is all too much, you may get the same good results in lowering blood pressure from the DASH diet.
Readers of this column may remember that chocolate contains compounds that activate the nitric oxide system in our bodies. The Kuna Indians who live off the coast of Panama drink lightly processed cocoa as their main beverage and do not show an increase in blood pressure with aging. It is hard to consume chocolate or cocoa regularly and not get an overdose of sugar and in some cases fats. However, by using plain unsweetened cocoa powder combined with xylitol, mashed banana or pomegranate juice, chocolate lovers can stay on a healthy diet!
Sadja Greenwood, MD, MPH back issues on this blog
Tuesday, September 21, 2010
Go to Health: Sugar - What's good about it, and what's Not
In the past 20 years we US citizens have gained a lot of weight. In 2007, 74% of us (adults) were overweight or obese. In children and adolescents, about 25% are overweight or obese, a tripling of the rate of 20 years ago. The speed of this development is alarming, and has many reasons - less time spent on physical activity, more TV & computer games, more cheap fast food, less available produce in inner cities, and the neglect of home cooking by busy people.
Sugars: Another reason for our weight gain relates to the sugars found in processed foods, from breakfast cereals to donuts, cookies, cakes, jam, candy, energy bars, deserts, soft drinks, etc. In 1900 the average yearly consumption of sugar was 5 lbs, and now it is 135 lbs per person! Sucrose – the sugar that comes from sugar cane and sugar beets, is a 50-50 mix of glucose and fructose. Glucose, derived from food, is the main sugar that circulates in our bodies, fueling our brains, muscles and body processes. Fructose is the main sugar in tree fruits, berries and melons. When fruits are eaten, fructose contributes to their good taste and to our health, because of the many other nutrients in these foods.
High fructose corn syrup (HFCS), however, is another story. Between 1970 and 1990, the consumption of HFCS increased 1000% in the US! It is a mixture of 55% fructose and 45% glucose, and is manufactured from corn. HFCS has been used in soft drinks because of it is 40% cheaper than cane sugar. Animal studies indicate that it contributes to greater weight gain, cardiac risk factors and non-alcoholic liver disease when compared to sucrose. A recent study from UCLA showed that pancreatic cancer cells grew more rapidly in the presence of fructose. HFCS is also implicated in high blood pressure. Researchers at the University of Colorado used survey data on 4,500 adults, and found that people said they consumed about 4 soft drinks a day, imbibing 74 grams of fructose. The more fructose they had in their diet, the more likely they were to have high blood pressure, even when adjustments were made for other factors causing hypertension, such as obesity, salt, or alcohol.
Public recognition of problems with HFCS has led some companies, such as Starbucks, to eliminate it from bakery products; some soft drink makers, such as Gatorade, have cut back on its use. Food companies such as Cargill and Archer Daniels Midland insist that the product is similar to ordinary sugar, and are trying to rename it ‘corn sugar’. Nutrition expert Michael Jacobson, director of Center for Science in the Public Interest, and founder of the Nutrition Action Health Letter, takes a somewhat similar stand by saying that the main issue is that people need to consume less sugar – “Soda pop sweetened with sugar is every bit as conducive to obesity as soda pop sweetened with high fructose corn syrup.”
What to tell ourselves about sugar:
1) As a species, we like the taste of sweet foods, and have receptors for them in our mouths. We evolved eating tree fruits and berries. This pattern will keep us healthy.
2) Refined sugar from cane and beets is all right for special occasions, but there are caveats, as follows …
3) Sugar beets make up about 50% of US sugar, and are mainly genetically engineered (Roundup Ready). ‘Superweeds’ are evolving to Roundup, so that more pesticides may be needed. There is currently a temporary ban on GE sugar beet planting in the US because of environmental concerns. Genetically modified cane sugar research is underway in Brazil, Argentina and India; vast amounts of land has been cleared in these countries to grow sugar. If we did not eat as much sugar, the land could be used for real food, or revert to forest. You can find organic cane sugar, which is not genetically modified, but it is more expensive, and much less likely to be used in processed foods.
4) All refined sugars except for xylitol , mannitol, sorbitol and maltitol contribute to tooth decay and tooth loss, which is a big problem, especially among uninsured, low-income children and adults.
5) Refined sugars are empty calories, and are usually combined in foods with other empty calories, such as refined flour and fat. These foods contribute to obesity, diabetes, and many other serious health problems, as mentioned in this article.
6) Sugar-laden foods displace natural foods such as fruits, vegetables, whole grains and protein in our diets. You can train yourself to satisfy your sweet cravings with tangerines, bananas, dried figs and dates – it takes time and persistence, but your body will be happy for your choices. Be sure to fill up on healthy foods, including protein, before you encounter sweets.
Sadja Greenwood, MD, MPH Back issues on this blog
Sugars: Another reason for our weight gain relates to the sugars found in processed foods, from breakfast cereals to donuts, cookies, cakes, jam, candy, energy bars, deserts, soft drinks, etc. In 1900 the average yearly consumption of sugar was 5 lbs, and now it is 135 lbs per person! Sucrose – the sugar that comes from sugar cane and sugar beets, is a 50-50 mix of glucose and fructose. Glucose, derived from food, is the main sugar that circulates in our bodies, fueling our brains, muscles and body processes. Fructose is the main sugar in tree fruits, berries and melons. When fruits are eaten, fructose contributes to their good taste and to our health, because of the many other nutrients in these foods.
High fructose corn syrup (HFCS), however, is another story. Between 1970 and 1990, the consumption of HFCS increased 1000% in the US! It is a mixture of 55% fructose and 45% glucose, and is manufactured from corn. HFCS has been used in soft drinks because of it is 40% cheaper than cane sugar. Animal studies indicate that it contributes to greater weight gain, cardiac risk factors and non-alcoholic liver disease when compared to sucrose. A recent study from UCLA showed that pancreatic cancer cells grew more rapidly in the presence of fructose. HFCS is also implicated in high blood pressure. Researchers at the University of Colorado used survey data on 4,500 adults, and found that people said they consumed about 4 soft drinks a day, imbibing 74 grams of fructose. The more fructose they had in their diet, the more likely they were to have high blood pressure, even when adjustments were made for other factors causing hypertension, such as obesity, salt, or alcohol.
Public recognition of problems with HFCS has led some companies, such as Starbucks, to eliminate it from bakery products; some soft drink makers, such as Gatorade, have cut back on its use. Food companies such as Cargill and Archer Daniels Midland insist that the product is similar to ordinary sugar, and are trying to rename it ‘corn sugar’. Nutrition expert Michael Jacobson, director of Center for Science in the Public Interest, and founder of the Nutrition Action Health Letter, takes a somewhat similar stand by saying that the main issue is that people need to consume less sugar – “Soda pop sweetened with sugar is every bit as conducive to obesity as soda pop sweetened with high fructose corn syrup.”
What to tell ourselves about sugar:
1) As a species, we like the taste of sweet foods, and have receptors for them in our mouths. We evolved eating tree fruits and berries. This pattern will keep us healthy.
2) Refined sugar from cane and beets is all right for special occasions, but there are caveats, as follows …
3) Sugar beets make up about 50% of US sugar, and are mainly genetically engineered (Roundup Ready). ‘Superweeds’ are evolving to Roundup, so that more pesticides may be needed. There is currently a temporary ban on GE sugar beet planting in the US because of environmental concerns. Genetically modified cane sugar research is underway in Brazil, Argentina and India; vast amounts of land has been cleared in these countries to grow sugar. If we did not eat as much sugar, the land could be used for real food, or revert to forest. You can find organic cane sugar, which is not genetically modified, but it is more expensive, and much less likely to be used in processed foods.
4) All refined sugars except for xylitol , mannitol, sorbitol and maltitol contribute to tooth decay and tooth loss, which is a big problem, especially among uninsured, low-income children and adults.
5) Refined sugars are empty calories, and are usually combined in foods with other empty calories, such as refined flour and fat. These foods contribute to obesity, diabetes, and many other serious health problems, as mentioned in this article.
6) Sugar-laden foods displace natural foods such as fruits, vegetables, whole grains and protein in our diets. You can train yourself to satisfy your sweet cravings with tangerines, bananas, dried figs and dates – it takes time and persistence, but your body will be happy for your choices. Be sure to fill up on healthy foods, including protein, before you encounter sweets.
Sadja Greenwood, MD, MPH Back issues on this blog
Sunday, August 29, 2010
Go to Health: Unwanted Pregnancy & Ella, the new emergency contraceptive
Have you noticed that sex scenes in movies almost never include any discussion of whether the woman is using the pill or an IUD, and whether the man has a condom? Stopping to talk about AIDS doesn’t happen either. Film producers are getting better about cigarettes, but apparently condoms are too risqué. There is even controversy about requiring actors in pornographic movies to be protected by condom use. Our inability to get real about sex and to make protection available translates into our high rate of unintended pregnancies. It is not surprising that the US has a higher rate of unintended pregnancy than other developed countries. In France, about one third of pregnancies are unintended. In the US our rate is close to 50%; married and unmarried women are included in this number. Of the 800,00 pregnancies in teenagers per year, over 80% are reported as unintended. One third end in abortion. Teens who become mothers are less likely to finish high school or find decent jobs, and more likely to live in poverty.
The most rational plan for sexually active females and males is to talk about contraception ahead of time and use highly effective methods such as the pill, the IUD and condoms. Teenagers need to rehearse the way they will handle such talks, as they are not easy at first. Since sexual desire often overtakes rational thinking, a ‘plan B’ is needed to prevent unintended pregnancy. It’s called emergency contraception, and the foremost pill on the market is called ‘Plan B’!
Plan B One-Step contains levonorgestrel, a progesterone-type hormone that is used in many birth control pills. It prevents pregnancy primarily by stopping ovulation (the maturation and release of eggs from the ovaries) or by preventing fertilization of the egg if ovulation has already occurred. Plan B One-Step also alters the lining of the uterus, making it less receptive to a fertilized egg. Plan B One-Step is available without prescription to women and men 17 and older; it consists of a single pill that should be taken as soon as possible after unprotected intercourse, or if the condom breaks or pills have not been taken regularly. (Men don’t take Plan B,, but can buy it for their partners.) Girls younger than 17 can get Plan B One-Step with a doctor’s prescription. Women who have been raped should ask for Plan B One-Step in the emergency room. Plan B One-Step can be used up to 5 days after sex but loses some of its effectiveness after 3 days. Other emergency contraceptive pills on the market are Plan B and Next Choice. These both contain two pills, with instructions to take them 12 hours apart. However, studies have shown that both pills can be taken together.
Ella: In mid August, 2010, the FDA approved a new emergency contraceptive that has been used in 22 European countries since October 2009 and is said to be considerably more effective than Plan B. Ella works by preventing ovulation – the release of an egg from the woman’s ovaries, and probably also by changing the uterine lining to make it less receptive. It is similar in chemical configuration to RU 486, and thus has aroused opposition from groups who oppose abortion. Studies have shown Ella to be more effective that Plan B, and useful for up to 5 days after sex. Ella should be available by prescription by October or November of 2010. The approval of Ella by the FDA has been seen as evidence of a shift in the influence of political ideology at the FDA. Approval of Plan B, on and then off prescription, was very slow and controversial, while the approval of Ella was faster and unanimous. Ella and Plan B should not be used if the woman is already pregnant, or breastfeeding.
The Copper T IUD is the most effective way to prevent pregnancy after unprotected sex, It can be inserted within 5 days after sex and is said to be 99% effective in preventing pregnancy. It can remain in place for 10 years, This method is not the best birth control for women who may be at risk for sexually transmitted diseases, as infections in the pelvic organs can occur with IUDs. However, for monogamous couples, the IUD is an excellent choice.
Final Thoughts: If you are reading this column and it doesn’t apply to you, pass on the information to a young person who may need it.
If anyone can explain to me why film-makers find it impossible to include the question of contraception in sex scenes, please leave me a message and let me know. Films have enormous influence on our consciousness, and could do a lot of good by being honest on this subject. The scenes could be made as funny or poignant as real life.
Sadja Greenwood, MD, MPH Past issues on this blog
Sunday, August 15, 2010
Go to Health: Ghrelin and Leptin – the hunger hormones
There are many influences that govern what, when and how much we eat. Clearly our family of origin, habits and thinking play a big role in this, and so do the temptations of sweet, salty and rich foods in every store and restaurant. Most of us probably want to get in touch with our body’s signals that tell us when and how much to eat. Several hormones are constantly playing an unseen and important role in this. Ghrelin (the word comes from “ghre" in Proto-Indo-European languages meaning “grow") is made in the stomach and pancreas; it stimulates hunger. To pronounce this word, make ghrel rhyme with dwell, then add an ‘in’. Leptin (derived from the Greek word ‘leptos’ meaning thin) is formed mainly in fat tissue and inhibits
appetite.
Ghrelin levels increase before meals and when blood sugar is low. Ghrelin stimulates hunger. The hormone circulates in the blood and affects areas of the brain that cause an increase in growth hormone and the dopamine reward area. The pleasurable aspects of food (and alcohol) are reinforced. Ghrelin has also been found to reinforce learning and memory (think of a hungry animal looking for clues to find food). Short sleep duration is associated with increased levels of ghrelin, increased hunger and obesity – so getting enough sleep is important to maintaining a normal weight.
Leptin is a hormone secreted mainly from fat cells – receptors are found in brain areas known to be important in regulating hunger, body temperature and energy expenditure. When an animal gains weight and has larger amounts of body fat, leptin levels rise. Normally, hunger and food intake go down, and body temperature rises. Leptin counteracts the effects of anandamide, a neurotransmitter that stimulates eating and binds to the same receptors as THC in marijuana. Anandamide makes food pleasurable, as does marijuana, while leptin signals the brain that the body has had enough to eat. A recent study in rats showed that animals fed a diet high in fructose became resistant to leptin, and gained more weight than animals on a diet with similar calories but without fructose. This study gives a clue to the rise of obesity in the US. It’s fine to eat fruit, but avoid sweetened drinks, especially if they contain fructose.
The ‘Appestat’ The regulation of appetite has been the subject of much recent research, primarily because of the marked increase in weight gain in our population. The hypothalamus in the brain is the main regulatory organ for appetite; it is influenced by ghrelin, leptin and many other hormones and neurotransmitters. Research indicates that it takes time for the brain to register a feeling of fullness after eating, possibly up to 20 minutes. People who eat rapidly, or are distracted by watching television, may eat more than they need, by ignoring and not waiting for the body’s signals of fullness. Foods that contain more water, fiber and/or protein have the greatest ability to promote feelings of fullness. Most vegetables, fruits and beans or animal foods fall into this category. Whole grain pasta, bread and cereal contain more fiber than foods with refined flour foods, and are 50% more filling. However, choosing healthy food when you are hungry, and confronted with foods like chocolate cake or cheeseburgers, takes considerable resolve! Carrying some nuts, fruit or dried fruit in your backpack or purse can help.
Self-knowledge There are many valuable ways to stay in touch with your body – meditation, conscious relaxation, mindful breathing, and slow walking, come to mind. Slow and conscious eating can also be a great help in staying in touch with your body’s need for the right amount of healthy food.
Sadja Greenwood, MD, MPH – back issues on this blog
appetite.
Ghrelin levels increase before meals and when blood sugar is low. Ghrelin stimulates hunger. The hormone circulates in the blood and affects areas of the brain that cause an increase in growth hormone and the dopamine reward area. The pleasurable aspects of food (and alcohol) are reinforced. Ghrelin has also been found to reinforce learning and memory (think of a hungry animal looking for clues to find food). Short sleep duration is associated with increased levels of ghrelin, increased hunger and obesity – so getting enough sleep is important to maintaining a normal weight.
Leptin is a hormone secreted mainly from fat cells – receptors are found in brain areas known to be important in regulating hunger, body temperature and energy expenditure. When an animal gains weight and has larger amounts of body fat, leptin levels rise. Normally, hunger and food intake go down, and body temperature rises. Leptin counteracts the effects of anandamide, a neurotransmitter that stimulates eating and binds to the same receptors as THC in marijuana. Anandamide makes food pleasurable, as does marijuana, while leptin signals the brain that the body has had enough to eat. A recent study in rats showed that animals fed a diet high in fructose became resistant to leptin, and gained more weight than animals on a diet with similar calories but without fructose. This study gives a clue to the rise of obesity in the US. It’s fine to eat fruit, but avoid sweetened drinks, especially if they contain fructose.
The ‘Appestat’ The regulation of appetite has been the subject of much recent research, primarily because of the marked increase in weight gain in our population. The hypothalamus in the brain is the main regulatory organ for appetite; it is influenced by ghrelin, leptin and many other hormones and neurotransmitters. Research indicates that it takes time for the brain to register a feeling of fullness after eating, possibly up to 20 minutes. People who eat rapidly, or are distracted by watching television, may eat more than they need, by ignoring and not waiting for the body’s signals of fullness. Foods that contain more water, fiber and/or protein have the greatest ability to promote feelings of fullness. Most vegetables, fruits and beans or animal foods fall into this category. Whole grain pasta, bread and cereal contain more fiber than foods with refined flour foods, and are 50% more filling. However, choosing healthy food when you are hungry, and confronted with foods like chocolate cake or cheeseburgers, takes considerable resolve! Carrying some nuts, fruit or dried fruit in your backpack or purse can help.
Self-knowledge There are many valuable ways to stay in touch with your body – meditation, conscious relaxation, mindful breathing, and slow walking, come to mind. Slow and conscious eating can also be a great help in staying in touch with your body’s need for the right amount of healthy food.
Sadja Greenwood, MD, MPH – back issues on this blog
Sunday, August 8, 2010
Go to Health: Almonds, Peanuts, and PlumpyNut
Almonds are a delicious food, and one considered heart-healthy - because of studies showing that they decrease blood sugar and insulin response after a meal, and also lower damage to ingested protein as it is metabolized. Researchers at the University of Toronto followed this study with a look at ‘the portfolio diet’, in which subjects with elevated cholesterol followed an eating plan containing many heart-healthy foods: oatmeal, beans, olive oil, soy products, fibrous vegetables and a daily ounce of almonds (20-24 almonds). LDL cholesterol decreased by 29.6% in 4 weeks, compared to a 33.3% decrease on lovastatin. The ‘portfolio’ concept was to combine many known heart-healthy foods. Researchers called almonds a ‘mini-portfolio’ because they contain several components stressed in the eating plan - vegetable proteins, fiber, and plant sterols (structural components in cell membranes that lower cholesterol in humans). Almonds also are a good source of vitamin E, magnesium, heart-healthy monounsaturated fat, protein and calcium. Adding a daily ration of almonds to a weight loss diet is helpful, as their fat content can prevent overeating. Following salmonella outbreaks from raw almonds in 2001 and 2004, the USDA has mandated that all almonds be pasteurized to reduce bacterial contamination. This move has been very distressing to the raw food community. Some unpasteurized almonds can still be found, labeled as such. Other people prefer the taste of roasted almonds, and are not concerned by the ruling.
Peanuts are believed to have been domesticated about 7000 years ago in Peru; they are members of the bean family and grow underground. The Portuguese took them to China in the 1600s and to Africa in the 1800s; they became important in the diet of both areas. Besides being high in protein (25% by weight), peanuts have numerous health benefits. In 2003, the FDA allowed the following health claim: scientific evidence suggests, but does not prove, that eating 1.5 ounces per day of most nuts, including peanuts as part of a diet low in saturated fat and cholesterol, may reduce the risk of heart disease. (1.5 ounces of most nuts is about 1/3 cup.) Peanuts contain as much antioxidant capacity as blackberries and strawberries, and are richer in anti-oxidants than carrots or beets. Certain of their antioxidants are increased by roasting. They are also a good source of resveratrol, a compound in some plants that is studied for its anti-aging effects and protection against heart disease and cancers. Resveratrol is known to be present in grapes and concentrated in red wine – for non-drinkers, peanuts are a good alternative. For dieters, and people dealing with diabetes, a 2002 study from the Harvard School of Public Health found that women who ate 5 or more 1 ounce servings of peanuts or other nuts per week reduced their risk of type 2 diabetes by almost 30%. A similar finding was found among women eating 5 tablespoons of peanut butter per week.
Peanut allergy can be serious; it affects .6 to 1% of the US population, but is much less common in developing countries – possibly due to different ways of processing the nut. Peanuts can be contaminated with a mold called aflatoxin that can be carcinogenic; processing peanuts at high temperatures makes this contamination unlikely in the US.
PlumpyNut is a high protein, high energy peanut based paste that also contains vegetable oil, powdered milk, sugar, vitamins and minerals. It was specially formulated by a French nutritionist in the 1990s for use in famine conditions in Africa, where it has been lifesaving for emaciated children. It comes in a foil-wrapped bar which the child can use to feed herself or himself. You can see the remarkable results of PlumpyNut feeding on the 60 Minutes program of Oct 21st, 2007, narrated by Anderson Cooper. Recently there has been serious controversy about the patent on PlumpyNut held by the French company that makes it. Regardless of this problem, PlumpyNut is distributed by Doctors Without Borders and other relief organizations, which are worthy of our support.
Sadja Greenwood, MD, MPH Back issues on this blog
Peanuts are believed to have been domesticated about 7000 years ago in Peru; they are members of the bean family and grow underground. The Portuguese took them to China in the 1600s and to Africa in the 1800s; they became important in the diet of both areas. Besides being high in protein (25% by weight), peanuts have numerous health benefits. In 2003, the FDA allowed the following health claim: scientific evidence suggests, but does not prove, that eating 1.5 ounces per day of most nuts, including peanuts as part of a diet low in saturated fat and cholesterol, may reduce the risk of heart disease. (1.5 ounces of most nuts is about 1/3 cup.) Peanuts contain as much antioxidant capacity as blackberries and strawberries, and are richer in anti-oxidants than carrots or beets. Certain of their antioxidants are increased by roasting. They are also a good source of resveratrol, a compound in some plants that is studied for its anti-aging effects and protection against heart disease and cancers. Resveratrol is known to be present in grapes and concentrated in red wine – for non-drinkers, peanuts are a good alternative. For dieters, and people dealing with diabetes, a 2002 study from the Harvard School of Public Health found that women who ate 5 or more 1 ounce servings of peanuts or other nuts per week reduced their risk of type 2 diabetes by almost 30%. A similar finding was found among women eating 5 tablespoons of peanut butter per week.
Peanut allergy can be serious; it affects .6 to 1% of the US population, but is much less common in developing countries – possibly due to different ways of processing the nut. Peanuts can be contaminated with a mold called aflatoxin that can be carcinogenic; processing peanuts at high temperatures makes this contamination unlikely in the US.
PlumpyNut is a high protein, high energy peanut based paste that also contains vegetable oil, powdered milk, sugar, vitamins and minerals. It was specially formulated by a French nutritionist in the 1990s for use in famine conditions in Africa, where it has been lifesaving for emaciated children. It comes in a foil-wrapped bar which the child can use to feed herself or himself. You can see the remarkable results of PlumpyNut feeding on the 60 Minutes program of Oct 21st, 2007, narrated by Anderson Cooper. Recently there has been serious controversy about the patent on PlumpyNut held by the French company that makes it. Regardless of this problem, PlumpyNut is distributed by Doctors Without Borders and other relief organizations, which are worthy of our support.
Sadja Greenwood, MD, MPH Back issues on this blog
Sunday, July 25, 2010
Go to Health: Walnuts
Recent studies on the benefits of eating walnuts have made nutrition headlines: a reduction in the risk of prostate cancer (in mice) and slower growth of breast cancers (also in mice). These unfortunate mice have been bred or treated to develop these particular cancers. Researchers say that it is too soon to draw conclusions for humans from these studies. However, there are several other good reasons to include walnuts in your daily diet. Walnuts, flax seeds, and to a lesser extent canola oil (buy organic forms of this oil) contain relatively high amounts of an omega-3 fatty acid called ALA (alpha-linolenic acid). ALA is a plant precursor to the EPA and DHA found in fish oil. Green leafy vegetables, exclusively grass-fed animals, seeds such as pumpkin seeds and a vegetable known as purslane also have ALA. ALA is converted to EPA and DHA in our bodies, although the conversion is incomplete. Omega-3 fatty acids, from fish and plant sources, are essential for the human brain and body. Besides its ALA content, walnuts have other health benefits which are under investigation. Read on!
No Weight gain: walnut consumption, even in sizable amounts, has not led to significant weight gain. A recent study from Loma Linda School of Public Health asked subjects (but not a control group) to add 1/3 of a cup of walnuts (~280 calories) to their daily food intake. They were given no other dietary guidelines. Participants showed no greater weight gain than the control group over a 6 month period. They ate slightly less food when adding the walnuts, in a voluntary manner. Similar findings have been seen among people who regularly eat other nuts. Nuts lead to satiety, and may make it easier to ignore candy, cake and other empty calories.
Preventing Heart Disease Another Loma Linda study looked at people with moderately high cholesterol levels; when they added slightly less than 1/3 cup of walnuts to their usual diet, their total cholesterol and triglyceride levels decreased significantly. Subjects with the highest baseline readings improved the most. Men with elevated levels of lipoprotein(a) showed a significant decrease in this protein; lipoprotein(a) may increase the risk of heart attack. Another Loma Linda study contrasted the effects of walnuts and fatty fish (fish contain the omega-3 fatty acids DHA and EPA). The fish diet – 2 weekly servings of 4 oz of salmon – decreased triglycerides and increased HDL (good cholesterol) more than the control diet or walnut diet. The walnut diet, adding 1/3 cup of walnuts 6 days a week – showed better effects on LDL cholesterol, and lipoprotein(a). The authors concluded that including walnuts and fatty fish in the diet was helpful in decreasing the risk of heart disease. (While fresh or frozen salmon has become very expensive, you can still find wild-caught Alaskan salmon in cans for about $4.00. Get the unsalted kind if possible.) Researchers at the University of Barcelona have recently shown that in addition to lowering cholesterol, walnuts can improve the elasticity of the arteries, allowing blood to flow more easily throughout the body. This is an important finding.
Melatonin in walnuts Melatonin is the hormone secreted by the pineal gland, behind our eyes, that regulates our sleep-wake cycle. Darkness causes its levels to rise, and bright light inhibits it. As we get older, our nighttime melatonin levels wane, making it harder to fall asleep or stay asleep. Melatonin also acts as an anti-oxidant that helps the body resist toxic molecules called free radicals. Free radicals, that can damage DNA, are thought to be important in aging, cancers, brain disease et al. Melatonin is made by plants as well as animals and is fairly abundant in walnuts. Researchers at the University of Texas in San Antonio found that when laboratory rats were fed walnuts, their blood levels of melatonin went up, as did the total antioxidant capacity of their blood. The researchers surmised that the combination of melatonin and omega-3 fatty acid in walnuts made these nuts unusually beneficial. I surmise that walnuts may be a perfect bedtime snack, and an easy food to have by your bedside when the dreaded two a.m. insomnia makes your world look impossible. Dried tart cherries are said to have a similar helpful effect on sleep, again due to their melatonin content.
Sadja Greenwood, MD,MPH back issues on this blog
:
No Weight gain: walnut consumption, even in sizable amounts, has not led to significant weight gain. A recent study from Loma Linda School of Public Health asked subjects (but not a control group) to add 1/3 of a cup of walnuts (~280 calories) to their daily food intake. They were given no other dietary guidelines. Participants showed no greater weight gain than the control group over a 6 month period. They ate slightly less food when adding the walnuts, in a voluntary manner. Similar findings have been seen among people who regularly eat other nuts. Nuts lead to satiety, and may make it easier to ignore candy, cake and other empty calories.
Preventing Heart Disease Another Loma Linda study looked at people with moderately high cholesterol levels; when they added slightly less than 1/3 cup of walnuts to their usual diet, their total cholesterol and triglyceride levels decreased significantly. Subjects with the highest baseline readings improved the most. Men with elevated levels of lipoprotein(a) showed a significant decrease in this protein; lipoprotein(a) may increase the risk of heart attack. Another Loma Linda study contrasted the effects of walnuts and fatty fish (fish contain the omega-3 fatty acids DHA and EPA). The fish diet – 2 weekly servings of 4 oz of salmon – decreased triglycerides and increased HDL (good cholesterol) more than the control diet or walnut diet. The walnut diet, adding 1/3 cup of walnuts 6 days a week – showed better effects on LDL cholesterol, and lipoprotein(a). The authors concluded that including walnuts and fatty fish in the diet was helpful in decreasing the risk of heart disease. (While fresh or frozen salmon has become very expensive, you can still find wild-caught Alaskan salmon in cans for about $4.00. Get the unsalted kind if possible.) Researchers at the University of Barcelona have recently shown that in addition to lowering cholesterol, walnuts can improve the elasticity of the arteries, allowing blood to flow more easily throughout the body. This is an important finding.
Melatonin in walnuts Melatonin is the hormone secreted by the pineal gland, behind our eyes, that regulates our sleep-wake cycle. Darkness causes its levels to rise, and bright light inhibits it. As we get older, our nighttime melatonin levels wane, making it harder to fall asleep or stay asleep. Melatonin also acts as an anti-oxidant that helps the body resist toxic molecules called free radicals. Free radicals, that can damage DNA, are thought to be important in aging, cancers, brain disease et al. Melatonin is made by plants as well as animals and is fairly abundant in walnuts. Researchers at the University of Texas in San Antonio found that when laboratory rats were fed walnuts, their blood levels of melatonin went up, as did the total antioxidant capacity of their blood. The researchers surmised that the combination of melatonin and omega-3 fatty acid in walnuts made these nuts unusually beneficial. I surmise that walnuts may be a perfect bedtime snack, and an easy food to have by your bedside when the dreaded two a.m. insomnia makes your world look impossible. Dried tart cherries are said to have a similar helpful effect on sleep, again due to their melatonin content.
Sadja Greenwood, MD,MPH back issues on this blog
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Go to Health: Walnuts
Recent studies on the benefits of eating walnuts have made nutrition headlines: a reduction in the risk of prostate cancer (in mice) and slower growth of breast cancers (also in mice). These unfortunate mice have been bred or treated to develop these particular cancers. Researchers say that it is too soon to draw conclusions for humans from these studies. However, there are several other good reasons to include walnuts in your daily diet. Walnuts, flax seeds, and to a lesser extent canola oil (buy organic forms of this oil) contain relatively high amounts of an omega-3 fatty acid called ALA (alpha-linolenic acid). ALA is a plant precursor to the EPA and DHA found in fish oil. Green leafy vegetables, exclusively grass-fed animals, seeds such as pumpkin seeds and a vegetable known as purslane also have ALA. ALA is converted to EPA and DHA in our bodies, although the conversion is incomplete. Omega-3 fatty acids, from fish and plant sources, are essential for the human brain and body. Besides its ALA content, walnuts have other health benefits which are under investigation. Read on!
No Weight gain: walnut consumption, even in sizable amounts, has not led to significant weight gain. A recent study from Loma Linda School of Public Health asked subjects (but not a control group) to add 1/3 of a cup of walnuts (~280 calories) to their daily food intake. They were given no other dietary guidelines. Participants showed no greater weight gain than the control group over a 6 month period. They ate slightly less food when adding the walnuts, in a voluntary manner. Similar findings have been seen among people who regularly eat other nuts. Nuts lead to satiety, and may make it easier to ignore candy, cake and other empty calories.
Preventing Heart Disease Another Loma Linda study looked at people with moderately high cholesterol levels; when they added slightly less than 1/3 cup of walnuts to their usual diet, their total cholesterol and triglyceride levels decreased significantly. Subjects with the highest baseline readings improved the most. Men with elevated levels of lipoprotein(a) showed a significant decrease in this protein; lipoprotein(a) may increase the risk of heart attack. Another Loma Linda study contrasted the effects of walnuts and fatty fish (fish contain the omega-3 fatty acids DHA and EPA). The fish diet – 2 weekly servings of 4 oz of salmon – decreased triglycerides and increased HDL (good cholesterol) more than the control diet or walnut diet. The walnut diet, adding 1/3 cup of walnuts 6 days a week – showed better effects on LDL cholesterol, and lipoprotein(a). The authors concluded that including walnuts and fatty fish in the diet was helpful in decreasing the risk of heart disease. (While fresh or frozen salmon has become very expensive, you can still find wild-caught Alaskan salmon in cans for about $4.00. Get the unsalted kind if possible.) Researchers at the University of Barcelona have recently shown that in addition to lowering cholesterol, walnuts can improve the elasticity of the arteries, allowing blood to flow more easily throughout the body. This is an important finding.
Melatonin in walnuts Melatonin is the hormone secreted by the pineal gland, behind our eyes, that regulates our sleep-wake cycle. Darkness causes its levels to rise, and bright light inhibits it. As we get older, our nighttime melatonin levels wane, making it harder to fall asleep or stay asleep. Melatonin also acts as an anti-oxidant that helps the body resist toxic molecules called free radicals. Free radicals, that can damage DNA, are thought to be important in aging, cancers, brain disease et al. Melatonin is made by plants as well as animals and is fairly abundant in walnuts. Researchers at the University of Texas in San Antonio found that when laboratory rats were fed walnuts, their blood levels of melatonin went up, as did the total antioxidant capacity of their blood. The researchers surmised that the combination of melatonin and omega-3 fatty acid in walnuts made these nuts unusually beneficial. I surmise that walnuts may be a perfect bedtime snack, and an easy food to have by your bedside when the dreaded two a.m. insomnia makes your world look impossible. Dried tart cherries are said to have a similar helpful effect on sleep, again due to their melatonin content.
Sadja Greenwood, MD, MPH back issues on this blog
No Weight gain: walnut consumption, even in sizable amounts, has not led to significant weight gain. A recent study from Loma Linda School of Public Health asked subjects (but not a control group) to add 1/3 of a cup of walnuts (~280 calories) to their daily food intake. They were given no other dietary guidelines. Participants showed no greater weight gain than the control group over a 6 month period. They ate slightly less food when adding the walnuts, in a voluntary manner. Similar findings have been seen among people who regularly eat other nuts. Nuts lead to satiety, and may make it easier to ignore candy, cake and other empty calories.
Preventing Heart Disease Another Loma Linda study looked at people with moderately high cholesterol levels; when they added slightly less than 1/3 cup of walnuts to their usual diet, their total cholesterol and triglyceride levels decreased significantly. Subjects with the highest baseline readings improved the most. Men with elevated levels of lipoprotein(a) showed a significant decrease in this protein; lipoprotein(a) may increase the risk of heart attack. Another Loma Linda study contrasted the effects of walnuts and fatty fish (fish contain the omega-3 fatty acids DHA and EPA). The fish diet – 2 weekly servings of 4 oz of salmon – decreased triglycerides and increased HDL (good cholesterol) more than the control diet or walnut diet. The walnut diet, adding 1/3 cup of walnuts 6 days a week – showed better effects on LDL cholesterol, and lipoprotein(a). The authors concluded that including walnuts and fatty fish in the diet was helpful in decreasing the risk of heart disease. (While fresh or frozen salmon has become very expensive, you can still find wild-caught Alaskan salmon in cans for about $4.00. Get the unsalted kind if possible.) Researchers at the University of Barcelona have recently shown that in addition to lowering cholesterol, walnuts can improve the elasticity of the arteries, allowing blood to flow more easily throughout the body. This is an important finding.
Melatonin in walnuts Melatonin is the hormone secreted by the pineal gland, behind our eyes, that regulates our sleep-wake cycle. Darkness causes its levels to rise, and bright light inhibits it. As we get older, our nighttime melatonin levels wane, making it harder to fall asleep or stay asleep. Melatonin also acts as an anti-oxidant that helps the body resist toxic molecules called free radicals. Free radicals, that can damage DNA, are thought to be important in aging, cancers, brain disease et al. Melatonin is made by plants as well as animals and is fairly abundant in walnuts. Researchers at the University of Texas in San Antonio found that when laboratory rats were fed walnuts, their blood levels of melatonin went up, as did the total antioxidant capacity of their blood. The researchers surmised that the combination of melatonin and omega-3 fatty acid in walnuts made these nuts unusually beneficial. I surmise that walnuts may be a perfect bedtime snack, and an easy food to have by your bedside when the dreaded two a.m. insomnia makes your world look impossible. Dried tart cherries are said to have a similar helpful effect on sleep, again due to their melatonin content.
Sadja Greenwood, MD, MPH back issues on this blog
Monday, June 28, 2010
Cannabidiol - a Little Known Compound in Marijuana
Cannabidiol, known as CBD, makes up about 40% of extracts from the cannabis plant. It is said to be non-psychoactive, and to counteract the psychoactive compounds known as THC. Researchers at the Canadian Department of Agriculture have found that hemp - the type of cannabis grown for fiber or in the wild in temperate climates - is low in THC and high in CBD. The plant that originated in hot climates has different genetics, and is high in THC but low in CBD. Most cannabis currently grown for street and medicinal use is the latter type, bred to be high in THC, low in CBD. This is important for growers, as CBD is known to block the effects of THC. In other words, CBD prevents a marijuana ‘high’. In addition, CBD has been found to have interesting and promising medicinal uses. Research reports on CBD are now found in the medical literature.
Pain/Sativex : Several recent studies have shown that CBD, often combined with THC, is effective against pain in patients with advanced cancer whose pain is not controlled by medicines like morphine.. Patients appreciate the lack of hallucinogenic side effects. CBD/THC extracts have also been helpful with pain and spasticity in patients with multiple sclerosis. Canada released a medicine called Sativex in 2005, which was licensed for use in patients with multiple sclerosis and cancer pain. Sativex is a mouth spray; its full effect is achieved in about an hour. It is a mixture of THC and CBD, derived from the whole plant. Sativex is currently being used in England and Spain, for multiple sclerosis, severe nerve pain, malnutrition due to AIDS, and nausea/vomiting from chemotherapy. The US FDA has approved Sativex for certain clinical trials for cancer pain.
Cancer: Research has shown that CBD may work as an anti-cancer agent with low toxicity. Researchers at CPMC in San Francisco have been working on the ability of CBD to inhibit the growth and spread of breast cancer cells in a mouse model. If the work goes well, clinical trials of CBD in human breast cancer patients may take place. CBD is also being studied as a therapy for leukemia and brain tumors known as gliomas.
Other Uses: CBD has been tested in schizophrenia, epilepsy, ulcerative colitis, and Crohn’s Disease. As yet, there are no definitive answers as to its efficacy.
CBD in the leaf: Some people with severe pain are chewing the green leaves of marijuana plants for relief. The balance between THC and CBD in the leaf is said to be helpful without giving hallucinations or a ‘high’. People differ in their response to the leaf. They find that if the leaf is green and newly harvested, they can get pain relief and stay sober, even energized, by simply chewing it. If leaves are heated or aged, however, certain effects of THC are felt, and users can become tired and feel unwell. Because of current laws on individual use, this is anecdotal information.
November Ballot: Californians will be voting in November on an initiative to legalize the recreational use of marijuana for those over 21, and to allow small residential cultivation of the plant. Local governments, but not the state government, will be able to tax and regulate marijuana. A bill is pending in the California legislature that would legalize, tax and regulate marijuana, which could generate income for the whole of California. Many proponents say that the initiative is the first step toward a rational drug policy, and will save millions by not putting users in prison. Opponents are anxious about addiction, driving under the influence, use of the drug by more teenagers, and a further proliferation of pot dispensaries. Stay tuned for a detailed discussion of the pros and cons of this important issue as November approaches.
Sadja Greenwood, MD, MPH back issues at on this blog
Pain/Sativex : Several recent studies have shown that CBD, often combined with THC, is effective against pain in patients with advanced cancer whose pain is not controlled by medicines like morphine.. Patients appreciate the lack of hallucinogenic side effects. CBD/THC extracts have also been helpful with pain and spasticity in patients with multiple sclerosis. Canada released a medicine called Sativex in 2005, which was licensed for use in patients with multiple sclerosis and cancer pain. Sativex is a mouth spray; its full effect is achieved in about an hour. It is a mixture of THC and CBD, derived from the whole plant. Sativex is currently being used in England and Spain, for multiple sclerosis, severe nerve pain, malnutrition due to AIDS, and nausea/vomiting from chemotherapy. The US FDA has approved Sativex for certain clinical trials for cancer pain.
Cancer: Research has shown that CBD may work as an anti-cancer agent with low toxicity. Researchers at CPMC in San Francisco have been working on the ability of CBD to inhibit the growth and spread of breast cancer cells in a mouse model. If the work goes well, clinical trials of CBD in human breast cancer patients may take place. CBD is also being studied as a therapy for leukemia and brain tumors known as gliomas.
Other Uses: CBD has been tested in schizophrenia, epilepsy, ulcerative colitis, and Crohn’s Disease. As yet, there are no definitive answers as to its efficacy.
CBD in the leaf: Some people with severe pain are chewing the green leaves of marijuana plants for relief. The balance between THC and CBD in the leaf is said to be helpful without giving hallucinations or a ‘high’. People differ in their response to the leaf. They find that if the leaf is green and newly harvested, they can get pain relief and stay sober, even energized, by simply chewing it. If leaves are heated or aged, however, certain effects of THC are felt, and users can become tired and feel unwell. Because of current laws on individual use, this is anecdotal information.
November Ballot: Californians will be voting in November on an initiative to legalize the recreational use of marijuana for those over 21, and to allow small residential cultivation of the plant. Local governments, but not the state government, will be able to tax and regulate marijuana. A bill is pending in the California legislature that would legalize, tax and regulate marijuana, which could generate income for the whole of California. Many proponents say that the initiative is the first step toward a rational drug policy, and will save millions by not putting users in prison. Opponents are anxious about addiction, driving under the influence, use of the drug by more teenagers, and a further proliferation of pot dispensaries. Stay tuned for a detailed discussion of the pros and cons of this important issue as November approaches.
Sadja Greenwood, MD, MPH back issues at on this blog
Monday, June 21, 2010
Cell Signaling via Hormones
You probably have a cell phone and you may have a computer; many of you contact the world and your friends with calls, texting, email, facebook, twitter, and old-fashioned talk. Within your body, your cells are connected in a much more intricate way, constantly signaling each other through the bloodstream, nerves, and direct or short distance contact. What goes on between your 10-100 trillion cells is amazing; no cell can live in isolation – survival depends on an elaborate intercellular communication network that coordinates the growth and metabolism of cells in diverse organs. In this column I will outline the function of endocrine glands that produce hormones, chemicals that circulate in the bloodstream and affect cells and organs throughout the body.
Endocrine Glands in the Brain
Hypothalamus: this tiny key gland, located near the center of the brain, regulates the anterior pituitary, increasing or decreasing its hormonal output. It regulates the autonomic nervous system, body temperature, and many other functions.
Anterior pituitary: this gland regulates growth hormone, the thyroid gland, the adrenal gland, the ovaries and testes, and milk synthesis in the breast
Posterior pituitary: this gland regulates uterine contraction, milk letdown, and kidney functions in men and women..
Pineal gland: located behind the eyes, the pineal regulates the sleep-wake cycle via the hormone melatonin. Bright light suppresses melatonin and wakes you up, darkness promotes melatonin secretion and puts you to sleep.
With all this happening in glands of the brain, it is clearly important to keep your brain safe and healthy. My advice – avoid brain injury by always wearing helmets for riding bikes or horses, and be very careful on motorcycles. Don’t hit soccer balls with your head, and don’t allow your children to do so. Football and boxing often injure the brain. Avoid drugs and excess alcohol. Treat high blood pressure, to avoid a stroke. Exercise daily and eat healthfully.
Some other Endocrine Glands
Thyroid Gland: located in the lower neck, the thyroid secretes hormones known as T3 and T4, that stimulate the body to consume oxygen, use energy, and thereby increase the rate of metabolism. They also promote protein synthesis. Calcitonin, produced by specialized cells in the thyroid gland, stimulates bone construction.
Adrenal Glands: Located above the kidneys, these glands put out cortisol, which stimulates glucose production, suppresses inflammation, and inhibits immune responses. They also produce aldosterone, which increases blood volume and blood pressure. The adrenals produce androgens, which give women increased facial hair, and become a source of estrogen for women after menopause. The inside of the adrenal glands produce epinephrine – the fight-or-flight hormone, which also increases blood pressure, heart rate and muscular readiness.
Pancreas: Located below the stomach and adjacent to the liver, this organ secretes insulin, which promotes the uptake of glucose from the bloodstream, enabling cells to use it for energy, and the liver to store it as glycogen. The pancreas also secretes glucagon, which acts in the opposite direction, increasing blood glucose levels when needed for activity.
Ovary: Estrogen, produced from pre-puberty to menopause, stimulates the growth of the uterus and its lining, as well as breast cells. It has many effects throughout the body and brain. Estrogen increases the secretion of cholesterol in bile, which is why women in their reproductive years are more prone to gall stones. Progesterone, produced by ovaries in the second half of the menstrual cycle, and during pregnancy, helps to sustain pregnancy. It also has favorable effects on the thyroid, bones, teeth, gums, joints and tendons.
Testis: Androgens from the testes, mainly testosterone, increase muscle mass and strength, deepen the voice and promote the growth of bodily hair. Testes also secrete some estrogen, which helps with bone strength.
There are other hormone secreting organs in the body as well, including the heart, kidneys, skin, gastrointestinal tract, and fat. Imagine all these hormones circulating in the bloodstream, influencing your trillions of cells. It gives me a feeling of awe - of evolution, of our closeness to other animals, who share these hormones, and of the wisdom of our bodies. Stay as healthy as you can, and your body should reward and amaze you with its intricate workings.
Sadja Greenwood, MD, MPH
Back issues at on this blog
Endocrine Glands in the Brain
Hypothalamus: this tiny key gland, located near the center of the brain, regulates the anterior pituitary, increasing or decreasing its hormonal output. It regulates the autonomic nervous system, body temperature, and many other functions.
Anterior pituitary: this gland regulates growth hormone, the thyroid gland, the adrenal gland, the ovaries and testes, and milk synthesis in the breast
Posterior pituitary: this gland regulates uterine contraction, milk letdown, and kidney functions in men and women..
Pineal gland: located behind the eyes, the pineal regulates the sleep-wake cycle via the hormone melatonin. Bright light suppresses melatonin and wakes you up, darkness promotes melatonin secretion and puts you to sleep.
With all this happening in glands of the brain, it is clearly important to keep your brain safe and healthy. My advice – avoid brain injury by always wearing helmets for riding bikes or horses, and be very careful on motorcycles. Don’t hit soccer balls with your head, and don’t allow your children to do so. Football and boxing often injure the brain. Avoid drugs and excess alcohol. Treat high blood pressure, to avoid a stroke. Exercise daily and eat healthfully.
Some other Endocrine Glands
Thyroid Gland: located in the lower neck, the thyroid secretes hormones known as T3 and T4, that stimulate the body to consume oxygen, use energy, and thereby increase the rate of metabolism. They also promote protein synthesis. Calcitonin, produced by specialized cells in the thyroid gland, stimulates bone construction.
Adrenal Glands: Located above the kidneys, these glands put out cortisol, which stimulates glucose production, suppresses inflammation, and inhibits immune responses. They also produce aldosterone, which increases blood volume and blood pressure. The adrenals produce androgens, which give women increased facial hair, and become a source of estrogen for women after menopause. The inside of the adrenal glands produce epinephrine – the fight-or-flight hormone, which also increases blood pressure, heart rate and muscular readiness.
Pancreas: Located below the stomach and adjacent to the liver, this organ secretes insulin, which promotes the uptake of glucose from the bloodstream, enabling cells to use it for energy, and the liver to store it as glycogen. The pancreas also secretes glucagon, which acts in the opposite direction, increasing blood glucose levels when needed for activity.
Ovary: Estrogen, produced from pre-puberty to menopause, stimulates the growth of the uterus and its lining, as well as breast cells. It has many effects throughout the body and brain. Estrogen increases the secretion of cholesterol in bile, which is why women in their reproductive years are more prone to gall stones. Progesterone, produced by ovaries in the second half of the menstrual cycle, and during pregnancy, helps to sustain pregnancy. It also has favorable effects on the thyroid, bones, teeth, gums, joints and tendons.
Testis: Androgens from the testes, mainly testosterone, increase muscle mass and strength, deepen the voice and promote the growth of bodily hair. Testes also secrete some estrogen, which helps with bone strength.
There are other hormone secreting organs in the body as well, including the heart, kidneys, skin, gastrointestinal tract, and fat. Imagine all these hormones circulating in the bloodstream, influencing your trillions of cells. It gives me a feeling of awe - of evolution, of our closeness to other animals, who share these hormones, and of the wisdom of our bodies. Stay as healthy as you can, and your body should reward and amaze you with its intricate workings.
Sadja Greenwood, MD, MPH
Back issues at on this blog
Tuesday, June 8, 2010
Go to Health - Save Your Eyesight
“Sans teeth, sans eyes, sans taste, sans everything” wrote Shakespeare in As You Like It about the final stage of life. All the world’s a stage is great poetry, but certain steps not available in Shakespeare’s time can preserve your eyesight into old age. (As far as teeth are concerned, visit your dentist! I’ll take up the tooth issue in a later column.)
Glaucoma: A regular checkup by an eye doctor to screen for increased pressure in the fluid of your eyes will detect glaucoma, an eye disease leading to progressive loss of sight. Treatment with medicinal eye drops and laser surgery is effective. Most people should start eye checks at age 35- 40, and follow the testing advice of their eye doctor. Older people, African Americans, Hispanics, and those with a family history of glaucoma are more at risk.
Cataracts are changes in the lens inside the eye that focuses light on the retina (in the back of the eye). When the lens becomes cloudy, vision is impaired. Some causes of cataracts can be avoided – excessive exposure to UV light – wear sunglasses on bright days, and when on the water or in the snow. Start using sunglasses early in life. Don’t smoke! Smoking is a risk factor for cataracts. Stay active and of normal weight, to avoid diabetes, another risk factor for cataracts. Cataracts can be successfully treated with surgery, with the implantation of a new lens.
Macular Degeneration is a deterioration of the central portion of the retina – the interior layer of the eye that transmits signals into the optic nerve. With the macula we see detail – to read, recognize faces, do crafts, and get around safely. There is a dry and a ‘wet’ form of macular degeneration – the wet form can give rapid loss of vision due to blood vessel leaking that scars the retina. Macular degeneration is more common among lightly pigmented people (‘whites’), in smokers, in people who are obese, and in those with a family history of the disease.
Prevention of macular degeneration is important and the following steps are part of a program for healthy living that you already know. The health of your eyes is not separate from the rest of your body:
*Stop smoking! It’s a risk factor for blindness.
*Eat lots of vegetables, especially leafy greens. Kale, spinach. collard greens, broccoli, green peas and Brussels sprouts are all good sources of the antioxidants lutein and zeaxanthin that are especially helpful for the retina. Prolonged cooking decreases the bioavailability of lutein, so steam your greens lightly, and eat a raw salad daily. Egg yolk is another good source of these antioxidants. Chickens that have been out in green pastures lay eggs with the deepest orange yolks, with more lutein.
*Eat fish and/or take fish oil supplements - the omega-3 fatty acids may reduce the risk. A 2009 study at the National Eye Institute in Bethesda showed that a diet with high levels of omega-3 fatty acids resulted in slower progression of macular degeneration (in mice), with improvement in some lesions. The mice also had lower levels of inflammatory makers, which may explain the protective effect.
*Exercise and maintain a healthy weight. A study from the University of Wisconsin found that people who were physically active were markedly less likely to develop macular degeneration.
*Wear sunglasses – they protect the retina
*See your eye doctor regularly
There is great beauty in this world, despite its terrible problems. To enjoy this visual beauty into old age, follow the steps in the column.
Sadja Greenwood, MD, MPH Leave me a message!
Glaucoma: A regular checkup by an eye doctor to screen for increased pressure in the fluid of your eyes will detect glaucoma, an eye disease leading to progressive loss of sight. Treatment with medicinal eye drops and laser surgery is effective. Most people should start eye checks at age 35- 40, and follow the testing advice of their eye doctor. Older people, African Americans, Hispanics, and those with a family history of glaucoma are more at risk.
Cataracts are changes in the lens inside the eye that focuses light on the retina (in the back of the eye). When the lens becomes cloudy, vision is impaired. Some causes of cataracts can be avoided – excessive exposure to UV light – wear sunglasses on bright days, and when on the water or in the snow. Start using sunglasses early in life. Don’t smoke! Smoking is a risk factor for cataracts. Stay active and of normal weight, to avoid diabetes, another risk factor for cataracts. Cataracts can be successfully treated with surgery, with the implantation of a new lens.
Macular Degeneration is a deterioration of the central portion of the retina – the interior layer of the eye that transmits signals into the optic nerve. With the macula we see detail – to read, recognize faces, do crafts, and get around safely. There is a dry and a ‘wet’ form of macular degeneration – the wet form can give rapid loss of vision due to blood vessel leaking that scars the retina. Macular degeneration is more common among lightly pigmented people (‘whites’), in smokers, in people who are obese, and in those with a family history of the disease.
Prevention of macular degeneration is important and the following steps are part of a program for healthy living that you already know. The health of your eyes is not separate from the rest of your body:
*Stop smoking! It’s a risk factor for blindness.
*Eat lots of vegetables, especially leafy greens. Kale, spinach. collard greens, broccoli, green peas and Brussels sprouts are all good sources of the antioxidants lutein and zeaxanthin that are especially helpful for the retina. Prolonged cooking decreases the bioavailability of lutein, so steam your greens lightly, and eat a raw salad daily. Egg yolk is another good source of these antioxidants. Chickens that have been out in green pastures lay eggs with the deepest orange yolks, with more lutein.
*Eat fish and/or take fish oil supplements - the omega-3 fatty acids may reduce the risk. A 2009 study at the National Eye Institute in Bethesda showed that a diet with high levels of omega-3 fatty acids resulted in slower progression of macular degeneration (in mice), with improvement in some lesions. The mice also had lower levels of inflammatory makers, which may explain the protective effect.
*Exercise and maintain a healthy weight. A study from the University of Wisconsin found that people who were physically active were markedly less likely to develop macular degeneration.
*Wear sunglasses – they protect the retina
*See your eye doctor regularly
There is great beauty in this world, despite its terrible problems. To enjoy this visual beauty into old age, follow the steps in the column.
Sadja Greenwood, MD, MPH Leave me a message!
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