A combination of healthy diet, moderate physical exercise, no smoking and limited alcohol consumption can lower women's risk of heart disease by as much as 83 percent and stroke by 75 percent, a study published today reports.
While each of those lifestyle guidelines has been known to be effective in reducing risk of heart disease individually, Boston researchers said they were surprised by the enormous benefits of collective lifestyle modifications. The results from the continuing Nurses' Health Study, reported in today's issue of the New England Journal of Medicine, provide the strongest evidence yet that relatively simple changes in lifestyle can lead to a dramatic reduction in the number of deaths caused by heart attack the leading killer of both women and men.
The preventive measures are ``old news,'' said Dr. Meir Stampfer, of the Harvard School of Public Health, the study's lead author. ``The new part is putting it all together and quantifying the benefits. Over 80 percent of these heart attacks could be prevented. ... Taken together with medical intervention, you could very drastically reduce the burden of heart disease in this country.''
``We're not asking people to run marathons,'' said Dr. Walter Willett, chairman of Nutrition at Harvard School of Public Health and a co-author of the study. ``Everyone could achieve these goals.''
Women with the lowest risk were nonsmokers who exercised at least 30 minutes per day, were not overweight (having a body mass index of 25 or less), consumed an average of half an alcoholic beverage per day and ate a healthier-than-average diet.
Although men on average suffer heart attacks about 10 years earlier than women, cardiovascular disease which also includes strokes has claimed the lives of more women than men each year since 1984. Because women generally think breast cancer to be a bigger threat to their health, ``many women have delayed intervention and treatment of heart disease, so it's really important to dispel that myth,'' said Dr. JoAnn Manson, chief of Preventive Medicine at Brigham and Women's Hospital, where the study is based.
The Nurses' Health Study began in 1976 when 121,700 women between the ages of 30 and 55 first provided detailed answers to a questionnaire. It covers 11 states and is the longest women's health study ever initiated. Stampfer and his colleagues have followed 84,129 female registered nurses for 14 years in the heart-disease portion of the study. They chose women who were initially free of cardiovascular disease, cancer and diabetes and surveyed them every two years.
During the course of the heart-disease study, 296 of the women died from cardiovascular disease and 832 had nonfatal heart attacks.
The study found cigarette smoking to be the most important individual risk factor. The researchers said that diet is probably the risk factor least understood by the public. ``People (think) that `fat is bad' and `low-fat' is healthy,'' said Stampfer. ``It's not that simple.'' According to Willett, some types of fat are far worse than others, and unsaturated fats can actually prove healthy.
The study is important, experts said, because it focused on behaviors that women can modify themselves. While recent advances in drugs to treat hypertension and cholesterol levels have proved beneficial, those interventions require a prescription, may be costly and may cause side effects. In contrast, the behavior changes recommended by the researchers are inexpensive, have no side effects and may also reduce the risk of other diseases, including cancer and diabetes.
