Archive 2006 2007 2008 2009

Q: Can pumpkin seeds help keep the prostate healthy or combat the symptoms of an enlarged prostate?  H.S., VIA THE INTERNET

A: They have been used to treat male urinary problems for centuries, and there is some evidence that pumpkin seed oil and extract can make urine flow more easily. But no study has shown that pumpkin seeds can actually maintain prostate health—that is, prevent enlargement of the prostate.

Pumpkin seeds are a healthy, tasty snack. Plain roasted seeds have 148 calories and 12 grams of healthy fat per ounce. They also have 14 milligrams of vitamin E (93% of the RDA) per ounce, as well as thiamin and folate (B vitamins), magnesium, iron, and zinc.

Q: Are starch-blocking pills a safe and effective way to diet?  M.R., VIA THE INTERNET

A: No. These products, such as Carb Crusher, Starch Away, and Slender Now System, claim that you can eat all you want and still lose weight—provided you take these pills, at a cost of $50 to $100 a month. The idea is that the pills block starch digestion. For example, if you ate cereal containing 240 calories and took a starch blocker, you’d absorb only 26 of the calories, or so the sellers claim. The pills usually contain an extract of white kidney beans, a protein compound that blocks an enzyme in the intestine (alpha amylase) and keeps it from breaking down starch, as it normally would do. Thus, in theory, the starch passes into your large intestine and is excreted.

Manufacturers cite lab studies to support their claims, but no human studies on these products have yet been published—and most investigators are involved financially with the manufacturers. The idea of starch-blocking may sound logical—and it’s impossible to say that the pills have no effect at all. But the protein in the pill, or most of it, is itself probably digested before it can block anything. Starch digestion begins in the mouth, and continues in the small intestine. Another problem: the body is likely to produce more alpha amylase than a pill could block. Still another is that undigested starch in your large intestine would cause gas, bloating, abdominal pain, and diarrhea. Customers who complain of such symptoms are told it’s a sign that the pills work.

Starch blockers are nothing new—the FDA took several such products off the market in the 1980s. There actually is an FDA-approved prescription drug (acarbose, brand name Precose) that does slow starch digestion. It is used only for people with diabetes as a means of blocking a rapid rise in blood sugar. Its effects are moderate, and it does not lead to weight loss. Side effects include gas and diarrhea.

No one, particularly people with diabetes, should take starch blockers sold over the counter.

Q: Is it true that having gum disease puts me at higher risk for a heart attack?  L.R., VIA THE INTERNET

A: Maybe. Some (but not all) studies suggest there’s a link between periodontal (gum) disease and cardiovascular disease. But that doesn’t necessarily mean that gum disease is actually a cause of heart disease and strokes. It may merely suggest that you are at increased risk—and even that isn’t certain.

One new study, in the journal Stroke, found that older people who had lost more than 10 teeth tended to have more plaque in the main arteries in the neck leading to the brain—a major risk factor for stroke—compared to those who lost fewer teeth. Tooth loss is a sign of long-term gum disease (current gum disease, oddly enough, was not linked to arterial plaque). Another recent study, from Harvard, looked at more than 40,000 men and found a link between tooth loss, as well as current periodontal disease, and stroke. Since some things that increase the risk of gum disease—such as age, smoking, and diabetes—also increase the risk of cardiovascular disease, these studies controlled for such factors.

There are many theories, some quite complicated, to explain a possible link. Notably, periodontal disease, a bacterial infection of the gums, may trigger inflammation elsewhere in the body, and chronic inflammation is now thought to contribute to atherosclerosis (plaque formation in the arteries that leads to coronary artery disease and stroke). A simpler explanation may be that people who take good care of their teeth and gums may have a more healthful diet and have better health habits in general, which in turn may help prevent heart attack and stroke.

So take good care of your teeth and gums. It may help you live longer

Q: Are knock knees a problem for exercise?  S.T., LOS ANGELES

A: Yes, they can be. People who are signi-ficantly knock-kneed are at increased risk for a variety of injuries when running or doing other high-impact exercise. Many people are somewhat knock-kneed, and depending on the severity, this can put added strain on the hips, knees, lower legs, ankles, and feet. A problem for knock-kneed runners is that this can make their feet roll inward too much (overpronate). To see if you are knock-kneed, stand straight with your feet hip-width apart and look in a mirror: if your kneecaps are not aligned with the center of your feet and turn inward, you have some degree of knock knee.

If you have knock knees (or are bowlegged) and are thinking about running or starting another high-impact activity, you might want to talk to an orthopedist or physical therapist. You may need to get orthotic devices for your shoes, start a special exercise program, or perhaps avoid high-impact exercise altogether. Cycling and swimming are safer alternatives.

Q: Raw fish isn’t safe because it may contain parasites. What about lox and nova?  R.L, NEW YORK CITY

A: It’s highly unlikely that these forms of commercially preserved salmon pose any danger. Lox is heavily salted, but not smoked. Nova (so called because Nova Scotia is a major source of salmon) is cold-smoked and less heavily salted. Salting does kill parasites, but theoretically they could survive cold-smoking. There have been no reports of parasitic infection from commercial lox or nova, as far as we could find. Furthermore, cold-smoked salmon is almost always frozen after smoking, which also kills parasites.

UC Berkeley Wellness Letter, February 2004