Sunday, July 26, 2009

The DASH Diet - Dietary Approach to Stop Hypertension

If your blood pressure is higher than you or your doctor would like, you may be pleased to know how you can help make things better. The DASH diet is a well-researched way to improve your health and your blood pressure. It emphasizes:
*fruits and vegetables
*fat free or low fat milk or yogurt
*whole grains – brown rice, whole wheat, oats, rye, barley, corn, quinoa
*lean meat, poultry or fish
*nuts, seeds and beans
*small amounts of oil or soft (non-hydrogenated) margarine.
*Sweets, soft drinks and added sugars should be very low in this diet.
*Salt and salty foods (read labels!) should be minimized to make the diet effective - try to lower your sodium intake to 1500 milligrams per day. 2/3 teaspoon of salt =1500 mg.
* alcohol can increase blood pressure: men should not drink more than 2 drinks a day, women not more than one.

The potassium found in fruits and vegetables and the calcium in dairy products or fortified soy milk are important in this diet. People have found that their blood pressure begins to decline within the first two weeks of adherence. Remember that celery is effective for lowering blood pressure, and pomegranate juice has also been found helpful. According to researchers at the U. of Maryland, if you already take medication to lower blood pressure, pomegranate juice or extract could make the effects of those drugs too strong, so check with your doctor. You may be able to reduce your dose of medications.

To make the DASH Diet work for you, details and plans for daily meals and snacks are needed. The National Heart, Lung and Blood Institute has a good explanatory website:
http://www.nhlbi.nih.gov/health/public/heart/hbp/dash/new_dash.pdf

Alternatively, search your local library for the DASH diet; they will probably carry books on the subject. Amazon has several books: ‘The DASH Diet Action Plan: Based on the National Institutes of Health Research’ by Marla Heller, or ‘Your Guide to Lowering Your Blood Pressure With DASH’.

While you explore the DASH Diet, you should know about other approaches that have been shown to lower blood pressure:
*30 minutes of brisk walking daily may keep some people off of medication, and lower the dose for others. Two walks of 15 minutes are also good. Get a pal; make it fun; contact the trees and birds. Biking, swimming and other sustained aerobic exercise will also work.
*weight loss: the Dash Diet and exercise will help with this. Every 2 pounds lost can bring down blood pressure 1 point. After a year of gradual weight loss,, your blood pressure might be normal.
*transcendental meditation has been studied at the University of Kentucky and found to be the most effective relaxation method for lowering blood pressure: http://www.tm.org/national-institutes-of-health. This method of meditation is now non-religious and easy to learn.
*Resperate: this device has been studied at Rush University and the Mayo Clinic, and found helpful in guiding users into deep slow breathing that lowers blood pressure. It should be used 15 minutes 3-4 times a week, and will only be effective as long as it is used. The price is $300, but it can be tried for a month for $25. www.resperate.com or call 877-988-9388.

One in 3 adults in the US have high blood pressure. It is important to pay attention to this problem, in order to avoid having a stroke, heart attack or heart failure. Use a home blood pressure cuff, and work with your doctor and nurse-practitioner to get normal readings!
Sadja Greenwood, MD, MPH

Monday, July 20, 2009

Go to Health - Salt - Sodium Chloride

Our tongue and palate taste foods that are sweet, salty, sour, bitter and savory (umami). Salt is essential for us, as it is found in our blood, cells, bones, and the fluid between cells. Salt is necessary for the function of our nerves and muscles. The digestion of food in our stomachs by hydrogen chloride also comes from salt. When humans were hunter-gatherers, we got salt from eating animals; they got theirs from finding salt in rocks, brackish water and brine springs. (The city of Buffalo is named for the buffalo who made a wide path to a salt lick near Lake Erie!) When we became farmers, we needed to find sources of salt for our diets; the story of how humans have found, prepared and traded salt is a fascinating one of early commerce. You can find it in "Salt - A World History" by Mark Kurlansky.

How much salt to we need? The answer varies – depending on our body size, the amount we sweat, and problems such as serious diarrhea or kidney disease. The present consensus is that adults need 1000 - 1500 mg of sodium a day, and should not get more than 2400 mg. However, we are now averaging 3436 mg a day. Sodium is present in all animal food we eat, in small amounts in vegetables, but in large amounts in bread and prepared foods, which make up 70-80% of our daily salt intake.

Why does excess salt in our diet matter? You know the answer – it has to do with high blood pressure (hypertension). Increased salt causes more fluid to be retained in the blood vessels, so the heart must work harder to pump blood through the body. Salt may also act on arterioles - blood vessels that dilate and constrict to regulate blood pressure and blood flow. By contracting under the influence of sodium, arterioles increase resistance to the movement of blood and thereby increase blood pressure. Genetics play a role in our sensitivity to salt – some people are more susceptible to high blood pressure, and sodium sensitivity appears to increase with age. African Americans tend to be more salt sensitive than others and should be especially careful to eat less salt. A national study showed that 29% of US adults have hypertension (systolic pressure consistently over 140, diastolic over 90 on multiple readings), and another 28% have prehypertension. (systolic pressure of 120-139, diastolic of 80-89 on multiple readings). An increased risk for heart disease and stroke is the reason for concern about blood pressure.

Since most of the salt in our diets comes from prepared food – be prepared to find it! Carefully read the labels on canned and dried soups, sauces, vegetable juices, salad dressing, lunch meats, bacon, bread, popcorn, crackers and chips. Most of us don’t have the time or desire to make everything at home, but we can all be detectives. Making more foods from scratch saves money as well as health. Your taste for lots of salt is reversible; decrease your use gradually and your taste buds will adjust. As you eat more fruits and vegetables you will be increasing the potassium in your diet. A potassium-rich diet blunts the effects of salt on blood pressure, may reduce the risk of developing kidney stones, and possibly decrease bone loss with age.

When you are on the go, pack fresh and dried fruit in your bag, along with carrots, celery and unsalted nuts. Try low sodium V-8, or Knudsen’s plain or organic low sodium Very Veggie.
Next week I’ll describe the DASH diet, and other ways to lower blood pressure, including the right kind of exercise, and gradual weight loss.
Sadja Greenwood, MD, MPH

Sunday, July 12, 2009

Go to Health: Celery and Purslane

Go to Health: Celery and Purslane

About 40% of medicines in the U.S. today come from plants—or are based on chemicals found in plants. Beyond that, nearly 70 percent of the Earth's 6.2 billion people rely on plant-based medicine. Here are two examples close to home that we may have ignored:
Celery – crunchy and familiar
Purslane - an amazing ‘weed’


Celery lowers blood pressure:
Scientists at the University of Chicago and at the Hunan Hematological Research Center in China have determined the mechanisms by which celery lowers blood pressure. Celery contains a chemical called 3-n-butyl phthalide, which relaxes the smooth-muscle lining of blood vessels, making them wider and thereby lowering blood pressure. Phthalide works by lowering the concentration of stress hormones in the blood, which constrict blood vessels. In studies with normal rats, a dose of phthalide equivalent to four stalks of celery in humans lowered blood pressure by an average of 13 percent. The same dose also lowered the rats' cholesterol levels by 7 percent. Celery contains 341 milligrams potassium and 125 milligrams sodium per 100 gram serving. Any food with a ratio of three parts potassium to one part sodium is good for people with high blood pressure. Small studies indicate that celery may also be helpful in reducing uric acid levels in gout.
Some people are allergic to celery. If that is not the case, try 4 stalks a day (not the leaves) for blood pressure problems, and check with your clinic and your home-based blood pressure cuff to see if it is useful.

Purslane has omega-3s and more:
Purslane was used in ancient Greece, Africa and India as a medicine. Found throughout the world, it reached the Americas by the 1400s. Purslane contains more alpha linolenic acid (ALA) than any other leafy green vegatable. ALA, also found in walnuts, flax seed and greens, is slowly converted by our bodies into the omega-3 fatty acids found in fish. Purslane has a higher mineral content than most vegetables we eat and has various potent antioxidants. After millennia of widespread use as a folk medicine, it is now being tested on a surprising variety of health problems.
*Oral lichen planus –a chronic condition affecting the lining of the mouth with white patches, which can be painful. Studies done in the US and Iran show that purslane capsules were helpful.
*Diabetes – preliminary animal studies in China show that purslane can lower blood glucose levels and raise HDL cholesterol (the good kind).

*Anti-aging effects – animal studies in China showed that purslane increased memory, mental activity and various biochemical signs of aging.
*Heavy uterine bleeding – Studies at the medical university in Qom, Iran showed that 8 out of 10 women whose abnormal bleeding did not respond to standard treatment had normal periods after taking purslane seed powder for 3 days after the onset of bleeding.
*Phytoremediation: Japanese scientists at the University of Osaka have found purslane can remove bisphenol A - an endocrine disrupting compound with estrogenic properties – from ground water. Indian scientists at the Sardar Patel Centre for Science and Technology have found that purslane picks up heavy metals in industrial effluent, and can be used to clean contaminated areas
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Go purslane, the 21st century vegetable! You can find purslane at some farmer's markets. You can buy seed on line; just search for purslane seed.
Sadja Greenwood, MD –back issues on this blog. Leave me your comments.