Strokes have tripled in recent years for women ages 35 to 54. To blame for this alarming figure is the obesity epidemic.

According to a federal health survey that zeroed in on the years 1999 to 2004, two percent of women in this age group suffered a stroke. In a previous survey, from 1988 to 1994, only one-half of a percent had strokes. Although these percentages are small -- most strokes occur in older people -- the sudden spike in middle age is still worrisome.

Researchers say female waistlines are about two inches bigger than they were a decade ago. This bulge, they believe, is correlated with the increase in strokes.

Also worthy of consideration is the fact that women's average body mass index -- a common yet often inaccurate measure of obesity -- increased from 27 to 29. Female blood sugar levels were also notably higher. Risk factors that did not change from survey to survey are smoking, heart disease, and diabetes. Obesity, then, seems to be the culprit.

Belly fat stands out, says study leader Dr. Amytis Towfighi -- the portion of women with abdominal obesity rose from 47 percent to 59 percent. This change was not so apparent for men which makes sense since studies show abdominal obesity is a stronger risk for women than men.

In the past, men have always suffered more strokes than women. Women are now catching up.