Diet Can Circumvent Heart Disease
Studies suggest vegetable tablets, whole grains and baked or broiled fish
MONDAY, May 2, 2005 (HealthDay News) -- New research pinpoints ways to protect your heart with what you put in your mouth.
Swallowing vegetable-based tablets with your statins if you take them, eating lots of whole grains, and cooking your fish just the right way can all guard against cardiovascular damage, say three studies presented Monday at the American Heart Association's annual conference on cardiovascular disease, epidemiology and prevention in Washington, D.C.
The first study found tablets made of plant stanols, which inhibit cholesterol absorption, further reduced LDL, or "bad," cholesterol levels in people already taking statins. The tablets could offer a convenient and cheap addition to standard cholesterol therapy, the researchers stated.
"Plant stanols are materials found in vegetable foods, and are able to inhibit the absorption of cholesterol," said study author Dr. Anne Goldberg, an associate professor of medicine at Washington University School of Medicine in St. Louis. "These compounds are now part of the [dietary] recommendations to help lower cholesterol, but trying to increase the amounts of them can be a little bit difficult. The ones that are available right now tend to be complex in fat. This can be a good way to lower LDL, but a lot of people don't want the extra calories."
For this study, 26 people on statins -- drugs designed to lower cholesterol -- were asked to follow a specific diet and were randomly assigned to take four plant stanol capsules twice a day or a placebo. At the end of nine weeks, participants taking the plant stanol tablets had a drop in LDL cholesterol of 9.1 percent.
"We also found that the higher the LDL to start with, the greater the reduction with plant stanols, suggesting that this may be very useful in people taking statins to provide an additional effect," Goldberg said.
The study was funded by Lifeline Technologies, which is planning to eventually market the tablets, probably as a food supplement, Goldberg noted.
A second study found that women eating diets rich in high-quality carbohydrate and soluble fiber, such as whole-grain breads, had lower levels of C-reactive protein (CRP), a marker for inflammation that has been associated with coronary heart disease.
This observational study included 15,033 women involved in the Women's Health Study, who had filled out a questionnaire on eating habits.
"The simple way to go is to concentrate on full grains, substitute brown rice for white rice, and eat lots of fruits and vegetables," said study author Emily B. Levitan, a doctoral candidate at the Harvard School of Public Health in Boston.
A third study looked at different ways of preparing fish to see what effect it had on cardiac structure and function.
"Fish intake is associated with a lower risk of several cardiovascular outcomes, including sudden death, stroke, atrial fibrillation and congestive heart failure, but the mechanisms of the benefits of fish are not well-established," explained study author Dr. Dariush Mozaffarian, who is with Brigham and Women's Hospital and Harvard Medical School, both in Boston.
Again, the study involved analyzing food questionnaires, this time from about 5,000 men and women.
"Intake of tuna or other baked and broiled fish was strongly associated with a lower heart rate, lower blood pressure and lower cardiovascular resistance, which is a measure of the stretchability of arteries," Mozaffarian said. "Fried fish intake was associated with worse cardiac structure and worse systolic function."
In other words, Mozaffarian added, "all fish meals may not be equal."
But fighting heart disease does not stop at the dinner table.
A final study found that aerobic activities such as jogging and biking can help lower triglyceride levels in overweight and obese people. This was a meta-analysis of 13 completed randomized, controlled studies.
"We found a reduction of about 16 milligrams per deciliter, or about 11 percent, and those changes appear to have occurred independent of any changes in body weight which were small, or body fat or body mass index," said lead author George A. Kelley. He is director of the meta-analytic research group at the School of Medicine in the Department of Community Medicine at West Virginia University.
"Lowering of triglycerides is important because it has been shown to be an independent predictor of heart disease," he said. "Statins have been shown to reduce triglyceride levels from 6 percent to 30 percent, so our results are comparable to the use of statins for the lowering of triglycerides."
While it's not clear why aerobic exercise had a specific effect on triglycerides and apparently little effect on cholesterol levels, Kelley said, "This is another example of the importance of aerobic exercise for reducing cardiovascular risk."
To learn more about heart disease, visit the American Heart Association.