Dear HEALTHbeat subscriber,

If you’re trying to keep your cholesterol in check, what should you eat? Or not eat? Conventional wisdom used to hold that eating cholesterol raised the level of cholesterol in the bloodstream. We know now that dietary trans fats are the real bad guys when it comes to increasing LDL (or “bad”) cholesterol. This week’s HEALTHbeat offers 11 dietary strategies for lowering your cholesterol. Also in this issue, Dr Celeste Robb-Nicholson, editor in chief of the Harvard Women’s Health Watch, discusses the role of radiofrequency waves in treating urinary incontinence.

Wishing you good health,


Nancy Ferrari
Managing Editor
Harvard Health Publications
HEALTHbeat@health.harvard.edu

In with the good

Different foods lower cholesterol in various ways. Some deliver soluble fiber, which binds cholesterol and its precursors in the digestive system and drags them out of the body before they get into circulation. Some give you polyunsaturated fats, which directly lower LDL. And some contain plant sterols and stanols, which block the body from absorbing cholesterol.

1. Oats. An easy first step to improving your cholesterol is having a bowl of oatmeal or cold oat-based cereal like Cheerios for breakfast. It gives you 1 to 2 grams of soluble fiber. Add a banana or some strawberries for another half-gram. Current nutrition guidelines recommend getting 20 to 35 grams of fiber a day, with at least 5 to 10 grams coming from soluble fiber. (The average American gets about half that amount.)
   
   
2. Barley and other whole grains. Like oats and oat bran, barley and other whole grains can help lower the risk of heart disease, mainly via the soluble fiber they deliver.
   
   
3. Beans. Beans are especially rich in soluble fiber. They also take awhile for the body to digest, meaning you feel full for longer after a meal. That’s one reason beans are a useful food for folks trying to lose weight. With so many choices — from navy and kidney beans to lentils, garbanzos, black-eyed peas, and beyond — and so many ways to prepare them, beans are a very versatile food.
   
   
4. Eggplant and okra. These two low-calorie vegetables are good sources of soluble fiber.
   
   
5. Nuts. A bushel of studies shows that eating almonds, walnuts, peanuts, and other nuts is good for the heart. Eating 2 ounces of nuts a day can slightly lower LDL, on the order of 5%. Nuts have additional nutrients that protect the heart in other ways.
   
   
6. Vegetable oils. Using liquid vegetable oils such as canola, sunflower, safflower, and others in place of butter, lard, or shortening when cooking or at the table helps lower LDL.
   
   
7. Apples, grapes, strawberries, citrus fruits. These fruits are rich in pectin, a type of soluble fiber that lowers LDL.
   
   
8. Foods fortified with sterols and stanols. Sterols and stanols extracted from plants gum up the body’s ability to absorb cholesterol from food. Companies are adding them to foods ranging from margarine and granola bars to orange juice and chocolate. They’re also available as supplements. Getting 2 grams of plant sterols or stanols a day can lower LDL cholesterol by about 10%.
   
   
9. Soy. Eating soybeans and foods made from them, like tofu and soy milk, was once touted as a powerful way to lower cholesterol. Analyses show that the effect is more modest — consuming 25 grams of soy protein a day (10 ounces of tofu or 2½ cups of soy milk) can lower LDL by 5% to 6%.
   
   
10. Fatty fish. Eating fish two or three times a week can lower LDL in two ways: by replacing meat, which has LDL-boosting saturated fats, and by delivering LDL-lowering omega-3 fats. Omega-3s reduce triglycerides in the bloodstream and also protect the heart by helping prevent the onset of abnormal heart rhythms.
    
    
11. Fiber supplements. Supplements offer the least appealing way to get soluble fiber. Two teaspoons a day of psyllium, which is found in Metamucil and other bulk-forming laxatives, provide about 4 grams of soluble fiber.

Out with the bad

Harmful LDL creeps upward and protective HDL drifts downward largely because of diet and other lifestyle choices. Genes play a role, too — some people are genetically programmed to respond more readily to what they eat — but genes aren’t something you can change. Here are some steps you can take:

Saturated fats. One way to lower your LDL is to cut back on saturated fat. Try substituting extra-lean ground beef for regular; low-fat or skim milk for whole milk; olive oil or a vegetable-oil margarine for butter; baked fish or chicken for fried.

Trans fats. Trans fats boost LDL as much as saturated fats do. They also lower protective HDL, rev up inflammation, and increase the tendency for blood clots to form inside blood vessels. The Institute of Medicine recommends getting no more than two grams of trans fats a day; less is even better.

Q: I have stress urinary incontinence and don’t want to have surgery. What can you tell me about Renessa?

A. Renessa is a procedure that uses radiofrequency waves to treat stress urinary incontinence — the kind caused by increased abdominal pressure from coughing, sneezing, laughing, lifting heavy objects, and certain recreational activities. The radiofrequency waves are delivered through a probe inserted into the urethra (the tube that carries urine from the bladder to outside the body). The probe reaches the upper urethra, near the bladder, and the heat generated by the radiofrequency waves causes the tissue in that area to scar, making it firmer and presumably more resistant to involuntary leakage.

Renessa was approved in 2005 for the treatment of stress urinary incontinence in women who aren’t candidates for surgery. It requires anesthesia but takes only about 20 minutes and can be performed on an outpatient basis. Follow-up studies are encouraging: in one study, 78% of 170 women reported improvement after one year. But so far, the only published studies of Renessa have been funded by the manufacturer, Novasys Medical. Moreover, there are no long-term data on its effects. That’s important, because heating the tissue injures it. While that may reduce incontinence in the short term, we don’t know how patients will be faring five or 10 years down the road.

I suggest that you try other noninvasive therapies, including bladder training and Kegel exercises. If you’re overweight, losing weight may also help. If these don’t work, talk to your clinician about established surgical options, all of which have a longer track record than Renessa. Before recommending Renessa, I’d like to see some long-term research that isn’t sponsored by the manufacturer.

This Question and Answer first appeared in the October 2009 Harvard Women’s Health Watch, available at www.health.harvard.edu/women.