Monday, May 30, 2011

Beets and Green Vegetables Relax Your Arteries

A recent conference on Nutrition and Health, sponsored by the University of Arizona, contained many useful ideas for everyday life. The problems with sugar, in last week’s column, were on the menu. Here is another topic.

Beets and Greens: These foods contain nitrates, which used to be considered harmful because of serious health problems when infants drank contaminated well water. However, it was found that the main problem was fecal bacteria in the wells, rather than excess nitrates. In the 1970’s, researchers found that dietary nitrates (NO3) are converted into nitric oxide (NO), in the presence of L-arginine (an amino acid) and oxygen. NO is an important ‘signaling molecule’ in the body, diffusing rapidly – as it is a gas – across cell membranes. It causes relaxation of the smooth muscles that line blood vessels, resulting in lower blood pressure and increased blood flow. Nitroglycerine works to lessen the pain of angina (chest pain resulting from lack of oxygen for the heart muscle) by its conversion to NO. Viagra works to simulate penile erection by the release of NO. The production of NO is elevated in people living in high altitudes, which helps them get more oxygen by dilation of the blood vessels in their lungs. NO transmits messages between nerve cells and is associated with memory, learning, sleeping, feeling pain, and depression.

Researchers at Wake Forest University studied volunteers over age 70 given a diet containing beet juice and high nitrate vegetables. The subjects were found to have increased blood flow to their brains, potentially helping to avoid dementia. Studies on beet juice, at the University of Exeter, found it enables people to exercise up to 16% longer. The amount of nitrate in studies on athletes was the equivalent of what is found in 2-3 red beets or a plate of spinach. Other vegetables high in nitrates are kale, lettuce, parsley, cabbage, celery, radishes and turnips.

People with high blood pressure may be interested to know that the DASH Diet (Dietary Approach to Stop Hypertension) may owe at least some of its effectiveness to an emphasis on green leafy vegetables. For those who want quick results without cooking, beet juice is available on line. Mix it with soda water or plain water, and start with a little at a time. A few people don’t feel well after drinking beet juice.

The Dash Diet This diet, which has been shown to be effective in lowering blood pressure, can work surprisingly well within two weeks. DASH is described on line at the WebMD site and also in the book – The DASH Diet Action Plan – based on the National Institutes of Health Research. This book has great reviews, and should be read by anyone who is serious about reducing blood pressure and possibly getting off of blood pressure medications. Of course, it is important to talk to your doctor about changing your medicines. For those who want to start the eating plan right away, here it is. Eat more vegetables, fruits and low or non-fat dairy foods. Eat less red meat, processed meat, sweets and foods high in fat. Eat more whole grains, fish, and poultry. Read labels carefully, and avoid foods high in salt. For snacks, try unsalted popcorn (avoid the buckets in movies!), unsalted nuts of all kinds, raisins, and low or non-fat yogurt. Don’t forget that the nitric oxide (NO) in green vegetables and beets will rapidly go to work for you, by relaxing your arteries, increasing blood flow, and lowering your blood pressure. And, of course, there’s moving the body, which is also good for you, your arteries and your blood pressure. See you on the trails!
Sadja Greenwood, MD, MPH

Tuesday, May 17, 2011

Go to Health: “Fructose is alcohol without the buzz”

So says Dr. Robert Lustig, Professor of Pediatric Endocrinology and director of the children’s obesity program at UCSF. His talk – Sugar: The Bitter Truth – has been watched over a million times on Youtube; I will try to summarize his points in this column.

The obesity epidemic in the US has been growing steadily since the public was told in the 1980s to decrease fats in their diet. The introduction of low-fat processed foods, laden with sugars for palatability, and devoid of fiber, laid the groundwork for our weight gain. Roughly half of teenage boys drink more than two six-packs of soft drinks every week. Today, one in 50 adults is severely obese (with a BMI of 40 or higher) and 34% of us are obese (BMI 30 or higher). The share of obese children has tripled in that time, to 17%. This is more than double the percentages of 30 years ago. Someone whose height is 5’6” is obese at 186 pounds; a 6’ person is obese at 221 pounds.

Understanding sucrose, glucose, fructose and starch: Sucrose is derived from sugar cane and sugar beets. It is 50% glucose and 50% fructose. High fructose corn syrup is 55% fructose and 45% glucose. From the point of view of the liver, they are about the same – neither is good for us. The fructose in whole fruit is fine, because it is encased in fiber, which slows its absorption. Whole fruits also have many beneficial compounds for health. Starch is a complex carbohydrate, made up of joined glucose molecules, used by many plants for energy storage. Our digestion easily breaks down most starch to glucose.

Glucose digestion: When we eat plants, from cabbage to potatoes, we break down their starch to glucose; this travels in the bloodstream to all our body cells for energy use. About a quarter of the glucose goes to the liver, where it makes glycogen – a useful and necessary storage compound for energy. A small amount is translated into fat.

Fructose digestion: When we eat or drink sugar (sucrose) or high fructose corn syrup (HFCS), the 50% or 55% that is fructose goes to the liver, as only the liver can metabolize it. This is in contrast to glucose, used by all our body’s cells. Some fructose is broken down into uric acid and excreted by the kidneys. Uric acid increases the risk of gout, and also elevates blood pressure. Much of it is metabolized to fat, leading to a problem called non-alcoholic fatty liver – rarely if ever seen before the recent sugar craze. Some of it goes into the blood stream as triglycerides, which become fat. As triglycerides rise, and body fat increases, cells become resistant to insulin. Insulin, produced by the pancreas, causes cells in the liver, muscle and fat to take up glucose from the blood, for energy production and storage. When blood glucose rises, due to the cells’ insulin resistance, diabetes results. A diet high in fructose also is associated with ‘leptin resistance’ – the body does not respond to the hormone called leptin that cuts off appetite. The eater keeps on eating.

Alcohol digestion: Alcohol is fermented sugar. When it enters the liver, it is digested in a way that is similar to fructose, resulting in high blood pressure, fat deposition in the liver (ultimately cirrhosis) and increased triglycerides in the bloodstream. Alcohol also leads to obesity (beer belly), insulin resistance and possible addiction. A small amount of alcohol, especially as red wine, is heart-healthy (1 five ounce glass for women, 2 for men). However, even small amounts of alcohol raise women’s risk for breast cancer.

What to do!
Here is the formula that Dr. Lustig gives to the families with children in his obesity clinic: He says it works – they lose weight – if they can follow it and stay off of soda.
1.Only drink water or plain milk
2.Eat carbohydrates with their natural fiber.
3.Wait 20 minutes before seconds.
4.Buy screen time minute for minute with physical activity. Screen time includes TV, DVDs, computer games, et al.
Look at 2 in this table. This would mean avoiding all foods made with sugar – cakes, cookies, pies, candy, ice cream, jam, syrup, the works. These foods were occasional treats one hundred years ago, and now they are everywhere, and often cheaper than real food. It also means eating whole grain pasta, 100% whole grain bread, and brown rice. Even Dr Lustig admits to an occasional dessert, and lets his kids eat ice cream on Sunday (according to another Youtube video). However, he still labels sugar a ‘toxin’ and would like FDA regulation. Others are calling for a tax on high-sugar soft drinks, which would decrease use and help pay for health care reform. Stay tuned for a discussion of this proposal. In the meantime – opt for water, unsweetened coffee and tea, and an orange for dessert!
Sadja Greenwood, MD, MPH back issues on this blog

Sunday, May 8, 2011

Go to Health – Cinnamon

This common and amazing spice was first grown in Ceylon (Sri Lanka) and was imported to Egypt, the Mediterranean world and Europe as early as 2000 BCE. Spices like cinnamon, that we take for granted, were great luxuries in times past; they were used for flavoring, to prevent food spoilage, and for treating many ailments. Cinnamon was found to inhibit bacterial growth in stored food, which was very useful before the days of refrigeration.

Blood Sugar lowering: Currently, the interest in cinnamon centers on its role in lowering blood sugar. A study in normal subjects from the University of Lund in Sweden showed that adding cinnamon to a meal significantly lowered blood sugar an hour later, and also delayed stomach emptying. A study from the Beltsville Human Nutrition Research Center (US Department of Agriculture) on men and women with type 2 diabetes showed that cinnamon (given as 1, 3, or 6 grams daily in capsules) significantly reduced fasting blood sugar, LDL cholesterol, total cholesterol, and triglycerides. This is important, as people with type 2 diabetes have an increased risk of heart disease and stroke. The results from 1 gram of cinnamon were effective, and this amounts to about 1/5th teaspoon per day. Cinnamon had a sustained effect on levels of blood sugars and fats, even if not consumed every day. The authors of this study note that a number of other herbs have been reported to yield blood-sugar lowering effects in patients with diabetes: bitter melon, Gymnema (see below), Korean ginseng, onions, garlic, and flaxseed meal. The authors write that cinnamon may work by increasing glucose uptake by cells and activating the synthesis of glycogen ( a normal storage compound for glucose). Also, cinnamon is believed to stimulate cell receptors for insulin.

Gymnema sylvestris is an herb from India where it has been used to treat diabetes since before modern medicine. It curbs sugar cravings, and may also stimulate insulin secretion. It is available in the U.S. (online and in some natural food stores) as a supplement. Not enough is known about its side effects and dosage levels, so people who use it should work with their health-care practitioner. It should not be used in pregnancy or at the time of any surgery.

Polycystic Ovary Syndrome is a disorder associated with infertility in women, who also have multiple cysts on their ovaries, elevated glucose, weight problems, excess body hair and menstrual irregularities. A study was published in 2007 from Columbia University showing that oral cinnamon (1 gram daily) improved their glucose levels. More studies are underway using cinnamon for this condition.

Brain chemistry: A professor of psychology at Ohio Northern University found that students scored higher on attention, memory and visual-motor response speed when smelling cinnamon or chewing cinnamon-flavored gum.

How much is enough? There is concern that a substance called coumarin in cinnamon may be toxic to the liver in certain sensitive individuals. Liver damage is reversible if cinnamon is stopped. Since the genetics of this potential problem is not worked out, it is prudent to use cinnamon as a spice rather than in large doses. People with diabetes should talk to their doctors or nurse practitioners about using 1/5th teaspoon a day on oatmeal, baked apples or other foods, in case their need for medications decrease. Other people can continue to use cinnamon sensibly on favorite dishes and enjoy the wonderful flavor of this spice.

I have enjoyed reading Healing Spices by Bharat B. Aggarwal as a takeoff for this column on cinnamon. Aggarwal is a molecular biologist and cancer researcher at the M.D. Anderson Cancer Center of the University of Texas in Houston. Look for a wonderful collection of spices at the Bolinas People’s Store, or at most natural food stores. Leave me a comment, or a question!
Sadja Greenwood, MD, MPH back issues on this blog.

Monday, May 2, 2011

Phthalates – what are they & how to avoid them

Phthalates are a class of chemicals added to plastics to increase their flexibility and durability. About a billion pounds per year are produced worldwide. They are found in the enteric coating of pills and supplements, in adhesives and glues, personal care products, medical devices, detergents, paints, printing inks, shower curtains, vinyl upholstery, car interiors and many other plastic products. They easily diffuse into the environment as plastics age. We all have phthalates in our bodies – from our diet, skin exposure (from personal care products) general environmental contamination and inhalation. Cheese, butter and meats are a source of phthalates in food, in part from plastic packaging.

Shana Swan at the University of Rochester School of Medicine has studied the exposure of pregnant women to phthalates. She has written that most findings concern male children, where she found a correlation between a shortened distance between the anus and penis, and a smaller penis size with higher concentration of phthalates in the mother’s urine during pregnancy. These measurements may indicate an anti-androgen effect of phthalates, which was also found in some experimental animals. Swan writes that sensitive biomarkers to assay human phthalate exposure have been available for a short time (10-11years), so that the long term effects may not yet be known. The necessary epidemiological studies are expensive and slow, so that animal studies and small human studies will be necessary. Results from these are controversial. Some recent studies have found correlations between low sperm counts and phthalate levels in men. . Studies on early puberty in girls have not reliably shown a correlation with phthalates at this point.

Studies on phthalate levels in pregnant women and their babies/children have been done in several universities. Women exposed to phthalates and pesticides in the workplace are more likely to take six or more months to conceive and to have lower birth-weight babies, according to a recent study at Erasmus Medical College in Rotterdam. Researchers at Mt Sinai (NYC), Cornell and the US Centers for Disease Control found that higher prenatal exposure to phthalates was connected to disruptive and problem behaviors in children ages 4-9. Behaviors included aggressiveness, and ADHD.

What you can do
Lowering exposure to phthalates is prudent, and especially important if you are pregnant or care for children. Body-care products containing phthalates are a source of exposure for infants. Read the ingredients whenever you buy a product: avoid personal care products (hair products, nail polish, deodorants, perfumes, lotions, etc) with DBP, DEP, BzBP. Be aware that the term ‘fragrance’ can mean that phthalates are present. This may mean a serious change in your use of body-care products and cosmetics. You can find safer cosmetics of all kinds at the website of the Environmental Working Group: www.ewg.org/skindeep/.

DEHP is used in PVC plastics. DMP is in insect repellents. Choose plastics with the recycling code 1,2 or 5. Codes 3, 6 and 7 may contain bisphenol A or phthalates. Parents should not buy soft plastic PVC toys for children. California has a law – signed by Governor Schwarzenegger – that bans products containing more than 0.1% phthalates from toys as well as baby bottles and other items that children can put in their mouths.

Something positive!
After reading about the widespread nature of phthalates in our environment, as well as bisphenol A, you are probably ready for some better news. Dr. B.B. Aggarwal, a cancer researcher at the University of Texas MD Anderson Cancer Center, has written a new book called Healing Spices in which he brings together ancient traditional medicine and modern medical research to show how herbs and spices can promote healing and health. I will report on his findings in subsequent columns. In the meantime, know that he has a chapter on cocoa and chocolate, and is also a strong proponent of turmeric. See his website – Curcumin – The Indian Solid Gold, and prepare to be surprised at the science on the actions of curcumin against cancer and other diseases. Curcumin is the active agent in turmeric. Make some curry for dinner!
Sadja Greenwood, MD, MPH – back issues on this blog