How safe is chaparral and does it cleanse toxins?

Q: I am taking chaparral as a supplement because I read that it cleanses toxins stored in the body. Is it safe to use?

A: Chaparral Larrea divaricata is a desert shrub that grows in Mexico and the Southwestern United States. It is also known as greasewood and creosote bush because of the distinctive tarlike fragrance of its tiny leaves. The odor is very strong after a rain, a unique and pleasing desert smell.

Native Americans made tea from the leaves of this plant to treat chicken pox, colds, diarrhea, menstrual cramps, pain, snake bites, skin disorders and rheumatism. Others have promoted it for an even longer list of ailments ranging from acne to dandruff, diabetes, PMS, sciatica, rheumatoid arthritis, ulcers, urinary tract infections and cancer. Chaparral is available today in capsules and tablets as well as tincture form.

Chaparral contains a powerful antioxidant called NDGA (nordihydroguaiaretic acid) that has been used as a food preservative and may account for some of its medicinal properties. But I don't recommend taking chaparral internally (as a tea or supplement) for any indication.

Although it has been linked to rare cases of kidney and liver dysfunction, it appears to be generally nontoxic. It does not cause hepatitis, as some sources state. But the tea tastes terrible and tends to give you nasty burps, and I haven't seen any scientific evidence showing that it is effective for any of the conditions for which it is so often recommended, including cleansing the body of toxins.

I do recommend chaparral for topical use. Mexican herbalists have long valued it for healing eczema and other kinds of skin irritation and inflammation, and I find that it works well, better than many pharmaceutical products. You can buy chaparral lotions or salves from stores that sell herbal preparations. If you live in an area where chaparral grows, you can make your own remedies from it.

To make a poultice, steep leaves in hot water until the liquid has a strong smell. Then soak a cloth in it, and apply it to the affected area. If a large portion of the skin is involved, add a liter or so of strong chaparral tea to a bath that you can soak in.

Blood pressure

Q: Can I ever stop taking medicine for high blood pressure to see if diet and lifestyle changes have brought my blood pressure back to normal?

A: Hypertension (high blood pressure) is the most common form of cardiovascular disease in the United States, affecting nearly one in three adults. High blood pressure is a threat because it makes the heart work harder, increasing its oxygen demands and contributing to angina (chest pain related to heart disease). Unchecked, high blood pressure increases the risk of heart attacks, stroke and kidney disease.

Some people can lower and control their blood pressure with healthy lifestyle measures - losing weight if necessary (even a 10 percent weight loss might do the trick), quitting smoking if that's an issue, limiting intake of caffeine (in coffee, tea and sodas) and alcohol, all of which can contribute to the problem, as well as cutting back on salt (processed foods are the biggest sources of sodium in today's Western diet) and practicing relaxation methods.

The last of these may be the most important, yet doctors often fail to emphasize the importance of learning how to relax the involuntary nervous system, which controls the tone of blood vessels. Meditation, yoga, breathing exercises and biofeedback training can all help. I recommend that you also check out a simple device called RESPeRATE (www.resperate.com) that teaches you to lower your blood pressure by changing your breathing patterns. If you've made and are maintaining these lifestyle changes, you might then try to cut down on your blood pressure medication. Do so gradually, and be sure to monitor your pressure at home - at least two to three times a day, both when you are calm and when you are not - to make sure that it doesn't start to rise. If it does, you'll have to return to the usual dosage of your medication. It would be best to make these changes under the supervision of your physician so you will not be alone in your efforts.

A large study from the U.S. Centers for Disease Control and Prevention published in the May 4, 2007, issue of Morbidity and Mortality Weekly Report that while most Americans who have high blood pressure are trying to bring it under control, 70 percent of them have failed. The CDC researchers collected information on more than 101,000 people and found that of the nearly 25,000 who had high blood pressure, 98.1 percent said they were doing at least one thing to lower it: Nearly 71 percent said they had changed their eating habits, 79.5 percent said they had reduced or eliminated the salt in their diets, 79.2 percent either didn't drink or had cut back on alcoholic beverages, 68.6 percent exercised, and 73.4 percent were taking medication. But the study showed that those efforts paid off in only 30 percent of all cases.

If you have a family history of hypertension, lifestyle measures may not be enough to keep your blood pressure under control - you probably will need some medication. But no one should depend on drugs alone. A healthy lifestyle, including relaxation practice, is also key to keeping blood pressure in the safe range.

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