For women only - questions and answers on women's health - includes an interview with Harvard Medical School researcher, JoAnn E. Manson - Cover Story

Nutrition Action Healthletter, March, 1995 by Bonnie Liebman

Men die younger of heart attacks. Men don't get menstrual periods. Men can't get pregnant. Men do most of the research.

Which of these reasons ex lain why scientists have done far more studies on diseases in men than in women? Any and all.

But that's beginning to change. In 1990, the National Institutes of Health set up an Office of Research on Women's Health to help solve the problem.

Now we've got the Women's Health Study, the Women's Health Initiative, the Women's Antioxidant and Cardiovascular Disease Study, and more. All told, they involve hundreds of thousands of American women.

This month, Nutrition Action talks to Harvard Medical School researcher JoAnn E. Manson, one of the architects of those massive studies. Though the studies won't be finished for years, says Manson, there's quite a bit we already know about women, diet, and disease.

Q: Do women know which diseases really threaten their lives?

A: Many don't. A woman's risk of dying from heart disease is six times as great as her risk of dying of breast cancer. Fully one-third of all women will die of heart disease. Most women, however, think that breast cancer is the leading cause of death.

It's understandable that there's a lot of anxiety concerning breast cancer. It does kill more premenopausal women than heart disease. But over their lifetimes, women are much more likely to die of heart disease.

Q: Why do people think that heart attacks strike only men?

A: Women get heart attacks ten to 15 years later than men. So we're really talking about a postmenopausal disease. But the stage is set for heart disease in adolescence and young adulthood. It develops over a lifetime.

Q: So fatty foods clog arteries in younger women and girls, but it happens much more slowly?

A: Yes. If you're 35, you're likely to have more fatty blockage in your blood vessels than if you're 20. The process speeds up after menopause.

I don't want to make a young premenopausal woman worry about developing a heart attack at any moment, but I also don't want women to be complacent about it. No one is immune from heart disease, and it's very important to adopt a healthy lifestyle early on.

Q: Are women with heart disease treated differently than men?

A: Yes. Symptoms of heart disease like angina - chest pain that occurs with exertion - are more likely to be ignored or overlooked in women. Women tend to get into an emergency room much later after having a heart attack and tend to get less aggressive management of their heart disease. Women are nearly twice as likely as men to die in the year following a heart attack. And women who undergo coronary bypass surgery or angioplasty also do worse than men.

But all of these adverse outcomes may be because women are older and have more advanced disease at the time that they're diagnosed and treated.

LESS DATA ON DRUGS

Q: Do we know less about heart disease in women than in men?

A: Yes. For example, there is evidence that cholesterol-lowering drugs help women - or men - who have a prior history of cardiovascular disease. But should you put healthy people on cholesterol-lowering medication when they have mildly or moderately elevated cholesterol? For men, the answer is yes. For women, we don't know.

Q: What about diet?

A: Eating less saturated fat and dietary cholesterol lowers blood cholesterol in both men and women, although genetics also plays a role. Every one percent drop in blood cholesterol should translate into a two to three percent fall in the risk of heart disease.

Q: How little sat fat is best?

A: Less than seven percent of calories is desirable. Less than recommended.

And there is increasing evidence that the trans fats in margarines and partially hydrogenated oils raise heart disease risk, perhaps by lowering HDL ["good"] cholesterol as well as raising LDL ["bad"] cholesterol.

Total fat should stay below 30 percent of calories to reduce the risk of cancer, heart disease, and obesity.

Q: Are other causes of heart disease the same in women and men?

A: Most are. For example, smoking is a potent risk factor. So is a family history of heart attack before age 60. And high blood pressure is extremely important. It increases the risk three to four times above that of a woman with normal blood pressure. Obesity is a very strong risk factor in both men and women, but physicians are more complacent about obesity in women.

Q: Why?

A: One reason is that a woman's fat tends to be distributed more in her lower body - hips, buttocks, and thighs - than in her upper body, especially the waist and abdomen. Lower-body obesity may be less of a risk factor for heart disease, diabetes, and high blood pressure than upper-body obesity, but it's not substantially increases the risk of diabetes. And many women - as well as men - have upper-body obesity.

Q: What about exercise?

A: Physical activity is very protective in both men and women, though it has been studied much less in women. It increases HDL cholesterol, lowers the risk of diabetes, lowers blood pressure over the long term, lowers the tendency for blood to clot, and is good for reducing stress [see "What Women Can Do"]