By Sally Squires
Tuesday, October 2, 2007
Many people live to eat, but what if you could eat to live?
That's the idea behind using foods -- from avocados, barley and beans to nuts, oatmeal and soy -- to control the high blood pressure and elevated cholesterol levels that are ticking time bombs for heart disease.
Diet is proving to be a powerful weapon that can rival the effectiveness of many medications. Plus, food comes with other benefits: It costs less than most drugs, has no dangerous side effects and, of course, includes the pleasurable act of eating.
Take the Dietary Approaches to Stop Hypertension (DASH) Diet, developed by the National Heart, Lung, and Blood Institute. DASH is rich in fruit, vegetables, beans and whole grains. It includes lean meat, skinless poultry and fish, as well as low-fat and nonfat dairy products. Nuts, olives and healthy oils, including olive and soft margarine, are important ingredients in DASH.
Sodium intake is also reduced on DASH. Americans consume an average 3,375 milligrams of sodium daily, according to the National Health and Nutrition Examination Survey. But a recent study comparing three levels of sodium intake, ranging from 1,200 milligrams daily to 3,300 milligrams with the DASH diet, found that 2,300 milligrams was most acceptable to participants.
As for lowering blood pressure, research shows that following DASH for 30 days cut systolic blood pressure -- the pressure during heartbeats -- by an average of 12 millimeters of mercury, an accomplishment that rivals many blood pressure medications.
Smart food choices can also have a big effect on cutting blood cholesterol. The National Cholesterol Education Program, the American Heart Association and the American College of Cardiology have long advised consumers to reduce the amount of unhealthy saturated fat, trans fat and cholesterol in their diets.
A few doctors go farther. California physician Dean Ornish, the Cleveland Clinic's Caldwell Esselstyn and Neal Barnard of the Physicians Committee for Responsible Medicine advocate a vegetarian diet to lower low-density lipoprotein (LDL), the so-called bad cholesterol, and help reverse blocked arteries. (Recent research suggests that this approach can also help control and sometimes reverse Type 2 diabetes.)
At the University of Toronto, David Jenkins, professor of nutrition and metabolism, and his colleagues have assembled a portfolio of foods that lower blood cholesterol a little. Subbing them for less healthful foods lowered cholesterol by as much as 30 percent, equal to the effects of some statin drugs.
This mostly vegetarian "Portfolio" plan includes plenty of fruit, vegetables and fiber-rich foods, including oatmeal, beans, whole-grain bread, cereal and pasta. Soy is another important ingredient, as are nuts.
Foods fortified with plant substances called stanols and sterols are also key to the Portfolio plan. In the intestines, plant stanols and sterols compete with dietary cholesterol for absorption. Eating two grams per day can help lower LDL by 6 to 15 percent.
Among the foods now fortified with stanols and sterols are some margarine (Take Control, Benecol and Smart Balance); orange juice (Minute Maid Heartwise), granola bars (Nature Valley Healthy Heart), cereal (Health Valley Heartwise), a smoothie-like drink (Promise Activ Super Shot) and chocolate (Cocoa Via.)
Cutting blood cholesterol levels used to mean eating very little fat -- and missing out on a lot of flavor. But the Portfolio approach proves otherwise. In a year-long study, participants ate a moderate-fat diet, with 30 percent of daily calories as fat. Nearly all of it came from healthy sources such as olive oil, avocados and nuts. (Participants ate about two ounces of nuts daily.)
Trouble is that none of these dietary approaches works for everyone. Body weight seems to be what separates those who respond well from those who don't. Overweight and obese people -- that is, those with a body mass index of 25 or higher -- get about half the cholesterol-lowering response from changes in diet as those at a healthy weight, says Penny Kris-Etherton, professor of nutrition at Pennsylvania State University.
The difference may result from C-reactive protein, a substance whose levels rise as inflammation occurs inside the body. Dubbed "a fire within" the body, this inflammation is caused by obesity, arthritis, inflammatory bowel disease, Type 2 diabetes, insulin resistance and gum disease, among other triggers. C-reactive protein levels appear to raise heart disease risk by promoting plaque buildup within artery walls.
As levels of C-reactive protein increase, foods lose their ability to lower blood cholesterol, as Kris-Etherton plans to report today at the annual meeting of the American Dietetics Association in Philadelphia.
How to combat that? Perhaps by adding more fiber to the diet. A study based on the National Health and Nutrition Examination Survey found that the higher the fiber intake, the lower the blood levels of C-reactive protein in people of all ages and health conditions.
Also, skip foods with processed white flour and added sugar. Research shows those foods can raise C-reactive protein levels, particularly in women.
Weight loss and more physical activity are other strategies. Both cut C-reactive protein levels in men and women. So did following a high-fiber DASH diet, suggesting yet again new ways to eat to live.