Ask the experts: answer to your questions from the leaders in natural medicine

Natural Health, Dec, 2001

Does fiber prevent colon cancer? I'm confused about whether I should eat a high-fiber diet to prevent colon cancer. Some studies say yes, but others say fiber encourages tumor growth.

JAMES GORDON, M.D., REPLIES: I wouldn't recommend cutting back on high-fiber foods. The negative studies you refer to appeared in the New England Journal of Medicine last year and created quite a stir in the media. They contradicted earlier findings that showed high-fiber, low-fat diets lower colon cancer incidence. However, contrary to what you may have heard, these research studies did not show that fiber encouraged tumor growth; they reported that fiber, in the form of supplements in one study and in fruits and vegetables in the other, did not necessarily prevent the colon polyps that can grow into tumors. That's a critical distinction.

It's also important to distinguish between high-fiber foods and fiber supplements. Little evidence supports taking fiber supplements to reduce your risk of colon cancer. But more than 20 studies show that fiber-rich foods, especially fruits and vegetables, may reduce colon-cancer risk.

High-fiber foods are thought to speed food through your intestines, thereby preventing your body from absorbing potentially carcinogenic food additives. Some researchers also believe that these high-fiber foods stimulate the production of substances that regulate cell growth in your colon, and provide an array of vitamins and minerals that may help stave off cancer.

But remember, eating a high-fiber diet shouldn't be your only concern. You also have to eat foods low in animal fat, which has been implicated in colon cancer and in other cancers.

A Fix for Heart Palpitations

I get heart palpitations. The herb motherwort seems to help, but is it safe? Is there anything else I can try?

CAROLYN DEAN, M.D., N.D., REPLIES: I'll assume that your doctor ruled out arrhythmia (abnormal heart rhythm) with an electrocardiogram and mitral valve prolapse (a malfunctioning of the heart valves) with an echocardiogram, two common and serious causes of heart palpitations.

If these conditions aren't the cause of your palpitations, it's safe for you to continue treatment with motherwort (Leonurus cardiaca) in doses of 2 to 4 dropperfuls of the liquid extract three times a day for as long as you want. But keep in mind that although motherwort may temporarily regulate your heart rate, the herb does not address the underlying cause of your heart palpitations. One possible cause is a magnesium deficiency. You need this mineral to produce energy, nourish your muscles, transmit nerve signals, and utilize calcium properly--all of which affect the health of your heart. Frequent muscle cramps, muscle spasms, or migraines would clinch the diagnosis. Ask your doctor to administer a red blood cell magnesium test to find out if your levels are too low.

If you're deficient, increase your daily intake of magnesium-rich foods by eating at least one daily serving of either leafy green vegetables like spinach and kale (preferably from organic farms, which tend to have sod higher in magnesium than conventional farms), nuts, seeds, or whole grains. Or take a magnesium supplement in a 400 mg dose per day. If you experience loose stools, cut back your dose until your stools return to normal.

Sweaty Yoga Safety

I recently tried my first Bikram yoga class and was dismayed to find the classroom heated to 100 degrees. Why is such a high temperature necessary?

JUDITH HANSON LASATER REPLIES: Instructors claim the heat loosens your joints and muscles and allows you to sweat out toxins. However, not everyone should practice yoga in such extreme heat. Avoid high temperatures if you have heart or kidney problems (heat can strain your heart and dehydrate you), if you have a fever or are recovering from an illness, or if you're pregnant (unless your doctor okays it).

Even if you're in good health, high-temperature yoga may not suit you. According to Ayurveda, the ancient form of medicine still practiced in India, people's body types, or doshas, cause them to crave or avoid certain temperatures. The three types are vata, kapha, and pitta. Vatas are usually slim and they tend to be cold and therefore seek hot temperatures. Kaphas are robust, have rounder bodies, and like heat (but not humidity). Pittas are also robust, but they tend to sweat and they hate hot temperatures. It sounds like you might be a pitta.

If you want to give the class another chance, drink water during and after the class to cool your body and replenish lost fluids. Also practice good hygiene by using your own yoga mat. If you have to borrow, shower before class (for the sake of the next student who uses the mat) and place a clean towel on top of the mat. Shower as soon as possible after class to wash away any heat-thriving bacteria on your skin.

Make Your Own Toothpaste

I'm not happy with my store's selection of toothpastes. Can I mix my own?

LAUREL VUKOVIC REPLIES: You can, and it's easy to do. The following homemade natural tooth powder does a great job of polishing my teeth and leaves my mouth feeling clean and refreshed. I also like it because it doesn't have that very sweet flavor found in conventional toothpastes.