In January 2008, results of a two-year clinical trial revealed that Zetia failed to show any benefits among patients who took it in combination with the statin Zocor (simvastatin) in a drug called Vytorin. In fact, the study showed that Vytorin didn't work any better than a statin alone and that fatty plaque accumulated in the carotid (neck) artery almost twice as fast as it did in patients who took only Zocor. (However, experts not connected with the study said the difference in plaque accumulation was slight.) Plaque is made up of deposits of cholesterol that can clog arteries leading to heart attacks and strokes.

In the study, known as ENHANCE, Zocor taken alone reduced LDL ("bad") cholesterol by an average of 41 percent; Vytorin reduced it by 58 percent. That would have been good news if the study hadn't also shown that the combination drug seemed to prompt more plaque accumulation than Zocor.

We haven't heard the last on this subject. A Congressional committee is investigating why the drug companies that make Vytorin delayed release of the study data for almost two years. And two other clinical trials now underway are testing whether the combination of Zetia and a statin prevents heart attacks and stroke as effectively - or better than - a statin alone. Another issue raised by the study was the question of risks to the liver posed by Zetia. Some patients were dropped after tests showed that their liver enzymes were abnormally elevated.

Commenting on the study, the American Heart Association (AHA) noted that while both drugs tested lowered cholesterol, neither reduced it to desirable levels. The AHA also said that the ENHANCE study "was not large enough or long enough to determine whether the combination drug is more or less effective than the single drug in reducing heart attacks or deaths" but that there were no statistically significant differences in the safety of the products.

If you're taking Zetia, don't stop without consulting your physician. I would not recommend it, however, as the only intervention for high cholesterol.

Andrew Weil, M.D.

Tieraona Low Dog, M.D., director of education for the Arizona Center for Integrative Medicine, says that PCOS is principally a metabolic problem and that many treatment approaches are similar to those for insulin resistance. For example, she says that exercise is "an absolute must - no exceptions!" This means exercising for at least 30 minutes every day.

I recommend the following dietary changes:

• Adopt my anti-inflammatory diet.
• Avoid conventionally raised beef and dairy products. (They may contain residues of estrogenic hormones used as growth promoters.)
• Increase your intake of whole soy foods, including tofu, tempeh, soymilk, and edamame. The isoflavones in soy may help with the hormonal imbalances.

Dr. Low Dog notes that a small study published in the July, 2007, issue of Fertility and Sterility showed that one-quarter to one-half teaspoon of cinnamon powder reduced insulin resistance in women with PCOS. She adds that two herbs used in Chinese medicine, peony and licorice, have been studied in PCOS, but she cautions that the recommended doses are rather high and may further elevate blood pressure. If you want to try these herbs, consider working with a practitioner of traditional Chinese medicine (TCM) who also may suggest dietary changes and acupuncture. To find a TCM practitioner in your area, contact the National Certification Commission for Acupuncture and Oriental Medicine at www.nccaom.org.

Andrew Weil, M.D.

Although the group recognizes the recently reported drop in breast cancer incidence, attributed mainly to declining use of hormone replacement therapy, it maintains that data linking radiation and environmental chemicals to breast cancer are "compelling." And it suggests that a critical factor in breast cancer risk may be exposure to endocrine-disrupting chemicals during childhood, adolescence and in the womb.

Rates of other diseases have also been rising with increased exposure to many of the chemicals discussed in the report, including birth defects and developmental disorders, childhood cancers, and asthma. Again, we have no proof of a causal relationship, just worrisome coincidence.

We have no conclusive evidence that environmental chemicals are responsible for the increase in breast cancer, either - although those 400-plus studies cited in the report testify to the fact that researchers suspect a connection and have been looking for a link. (Obesity, a recognized risk factor for breast cancer, also has risen markedly in the same time period.)

We may never know for sure exactly what causes breast cancer. I discussed this report with Ruby Senie, Ph.D., a breast cancer epidemiologist at Columbia University in New York. Given the huge number of synthetic chemicals to which we are likely exposed "in combinations too numerous to imagine," Dr. Senie says, "There is no way that any epidemiologic study can adequately assess breast cancer risk due to any specific potential carcinogen."

The chemicals won't go away any time soon, so it's up to you to protect your health by eating foods high in antioxidants. Select organic varieties when it comes to foods that tend to have high pesticide residues. (For guidance, check the Web site of the Environmental Working Group at www.ewg.org.) Take a good quality antioxidant multivitamin-mineral every day as insurance against dietary gaps. The long-term solution may be more and better regulation of the chemicals in our environment, but that will come only if we, as citizens, demand it.

Andrew Weil, M.D.

It may be possible, however, to develop intolerances to foods you eat often - you may find you are less able to digest them than you used to be or that you react badly to some of them. But with certain exceptions (lactose intolerance, gluten intolerance) food intolerances are highly individual and mysterious. In some cases they are triggered by physical or emotional stress or exposure to environmental toxins. Lactose intolerance stems from a deficiency of the enzyme lactase, which is needed to help digest lactose, a sugar in milk. Individuals with this problem develop bloating, abdominal pain and, often, diarrhea when they consume milk. Gluten intolerance is caused by an abnormal immune response to gluten, the major protein in wheat and some other grains. These problems have a genetic basis.

Some people react to natural substances like the histamine in foods such as cheese, some wines and certain fish, particularly tuna and mackerel. Eating a food with a high level of histamine can lead to what seems to be an allergic reaction but is really just a response to the effects of the compound, sometimes called "histamine toxicity."

I encourage you to vary your diet - include as much fresh food as possible, minimize your consumption of processed foods and fast food and eat lots of fruits and vegetables. If you follow my anti-inflammatory diet, you'll get the vitamins, minerals, essential fatty acids and dietary fiber you need for optimal health.

Andrew Weil, M.D.

Affected children may have trouble following spoken directions. (When they get older, you may have to give them written directions.) They may also have problems in social settings if they can't process what is being said or express themselves normally. This diagnosis isn't in any way related to a child's intelligence. In fact, these youngsters often have above-average IQ'S.

Mixed receptive language disorder can be treated with speech and language therapy. Some kids may also need psychotherapy to deal with emotional or behavioral problems resulting from their inability to understand language and express themselves.

In addition, I would recommend giving them omega-3 fatty acids, which play an important role in normal brain development and function. My colleague Sandy Newmark, M.D., a pediatrician, advises that the correct dose of fish oil is 15-20 mg per pound of a child's body weight. Nordic Naturals makes a liquid product that can be measured out in the correct dose. Dr. Newmark also suggests making sure that that affected children get plenty of antioxidant vitamins and minerals from fruits and vegetables. Many pediatricians recommend that you don't give youngsters supplements until they've reached the age of four, but then you could consider a good multivitamin containing antioxidants to supplement what kids get from their diets.

Andrew Weil, M.D.

Some animal studies have found that maca increases sexual function, but I've been able to find only two human studies, both questionable. One showed improved libido among men between the ages of 21 and 56 who took either 1,500 or 3,000 mg of maca for 12 weeks. The Peruvian researchers who conducted the study found no difference in hormone levels among the men, suggesting that the change in libido couldn't be attributed to a direct effect of maca on male hormones. Statistical flaws in the study also weaken its conclusions. A second study conducted by same research group showed an improvement in sperm production and sperm motility (movement) in nine healthy men aged 24 to 44 who took either 1500 or 3000 mg of maca daily for four months. Again, no changes in hormone levels were seen, and, again, poor methodology casts doubt on the validity of the findings.

Dr. Low Dog notes that there is a growing body of basic science studies of maca as well as some animal data. While the safety profile of maca appears to be good, we have virtually no evidence from clinical trials demonstrating effectiveness in humans for anything. I'm sure maca is a nutritious component of the Andean diet, but given the lack of scientific information on any of the claimed health benefits, I see no reason to take maca supplements.

Andrew Weil, M.D.

While pe min gan wan is generally well-tolerated by patients, Dr. Horwitz says that the natural remedies he prefers for allergic rhinitis are khella tea, stinging nettle, and quercetin, along with saline nasal irrigation (neti pot or NeilMed Sinus Rinse bottle).

He notes that another TCM formulation is going to be studied among patients with asthma in an FDA-approved clinical trial at Mount Sinai School of Medicine in New York City. The formula contains extracts of a mixture of the raw herbs: Ling-Zhi 20 g, Ku-Shen 9 g, and Gan-Cao 3 g. Ling-Zhi is Ganoderma lucidum (reishi mushroom); Ku-Shen is made from roots of Sophora flavescens or S.angustifolia (yellow mountain laurel); and Gan-Cao is made from the root of a licorice relative, Glycyrrhiza uralensis.

Dr. Horwitz says he frequently recommends licorice root, one of the ingredients in the formula, to patients with asthma.

Andrew Weil, M.D.

I reviewed your question with Randy Horwitz, M.D., Ph.D., medical director of the Program in Integrative Medicine. He stressed that the most important aspect of treating a presumed hydrocele is accurate diagnosis. The main concern is to make sure that the problem isn't an incarcerated inguinal hernia, a potentially life-threatening condition that can occur when part of the intestine pushes through a weak spot in the inguinal canal (an opening between layers of abdominal muscle near the groin) and becomes trapped there. These cases require surgery. Another possible cause that is rare in the United States but common in less developed countries (and can occur among men who travel to these areas) is filiarisis (elephantiasis), an infection caused by a parasitic worm.

Dr. Horwitz says that in most cases patients just need reassurance that the condition is not harmful. Surgery may be indicated if the skin of the scrotum is irritated or weakened by chronic pressure or if the diagnosis is uncertain. Neither Dr. Horwitz nor I know of any natural remedies for hydrocele.

Andrew Weil, M.D.

Drugs get into the water supply when we take pills and excrete amounts that our bodies don't absorb. Bit by bit, the excess goes into wastewater, which is treated before being recycled back into reservoirs and is cleaned again before being piped into homes.

If you read news reports of the Associated Press (AP) investigation that revealed the presence of drugs in water supplies nationwide, you know that different drugs were found in different areas. Tests in Tucson where I live found three medications, an antibiotic, an anticonvulsant, and the byproduct of a heart medication. The federal government doesn't require that water be tested for drugs and hasn't set safety limits for drugs in water. Of the 62 major water providers the AP contacted during its investigation, only 28 tested for drugs.

Some of these lapses are pardonable: until recently, we didn't have tests sensitive enough to detect the trace amounts of drugs the AP investigation identified. Fortunately, the stir kicked up by these findings has prompted some states and municipalities to begin testing their water supplies. Congressional hearings have been promised.

Unfortunately, at present, there's not much individuals can do to protect their personal water supplies. Most home water filtering systems aren't designed to remove drug traces, and bottled water isn't tested for pharmaceuticals either. Only one filtering technology, reverse osmosis, can remove drug traces, but it is expensive and, depending on the system, uses three to nine gallons of water for every one gallon that you get filtered. These systems are also very slow - you may have to wait for up to four hours for it to produce a gallon of drinkable water.

In my home and offices I use a water distiller called D-3. I've always thought distillation, rather than filtering, was the best water purification method and that distilled water is best for drinking. Distillation will reliably remove more contaminants than other purifying systems and is cheaper than bottled water in the long run.

I'll follow this issue closely as we learn more about the extent of the drug residue problem and its ramifications and will keep you posted on developments.

Andrew Weil, M.D.

I've read a few reports that saw palmetto can promote hair growth in men. Some people even recommend squeezing out the contents of saw palmetto soft gel capsules and rubbing it into the scalp. I think the effect, if any, is modest.

However, James A. Duke, Ph.D., a leading authority on healing herbs and author of The Green Pharmacy, explains that saw palmetto may promote hair growth because it inhibits conversion of the male sex hormone testosterone to dihydrotestosterone (DHT). DHT is involved in prostate enlargement and also plays a role in the destruction of hair follicles that leads to male pattern baldness. In Dr. Duke's Essential Herbs, he says he has collected a number of uncontrolled case studies suggesting that saw palmetto triggers hair regrowth. Dr. Duke recommends the same dose that I recommend for BPH.

In "The Green Pharmacy," Dr. Duke lists several other herbs that might help prevent hair loss:

• Licorice (Glycyrrhiza glabra), which also prevents conversion of testosterone to DHT. Dr. Duke suggests adding licorice to your shampoo.
• Rosemary (Rosmarinus officinalis), which may encourage hair growth by stimulating circulation when mixed with an oil and rubbed into the scalp. Dr. Duke noted that naturopaths often suggest nightly scalp massage with one part rosemary oil and two parts almond oil.
• Danshen (Salvia miltiorrhiza) and sage (Salvia officinalis), which Dr. Duke says have the reputation of preventing hair loss and retaining hair color. He suggests adding a few teaspoons of sage tincture to your shampoo.

In his book,Dr. Duke mentions stinging nettle (Urtica dioica) for baldness prevention in those with thinning hair. The source he cites is Rudolf Fritz Weiss, M.D., a German herbal physician and author who recommends tincture of nettle. Duke says that he knows of no research supporting this recommendation but respects Weiss. Dr. Duke includes sesame seeds, horsetail and safflower as additional possibilities.

I know of no evidence suggesting that pumpkin seed, pygeum (Pygeum africanum), or zinc is useful. And I know of no other herbs or supplements that would help.

Andrew Weil, M.D.