Women who were overweight at age 18 may be at greater risk of premature death than those who weren’t.

That finding comes from a study published in the Annals of Internal Medicine.

The 12-year study included 102,400 female American nurses. When the study started in 1989, the nurses were 24 to 44 years old. They reported their current height and weight, their height and weight at age 18, and their history of smoking, drinking alcohol, and physical activity.

The nurses were then followed for 12 years by the researchers, who included Rob van Dam, PhD, of the nutrition department at Harvard School of Public Health.

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Rare Cases of Premature Death

The vast majority of participants were still alive at the end of the follow-up period, regardless of weight.

However, 710 nurses -- less than 1 percent of the entire group -- died during the follow-up period. Given their young age -- 56 years old, at most -- the researchers considered all of those deaths to be premature.

Premature death risk was higher for nurses who had been overweight or obese at age 18, even if they had only been moderately overweight based on their BMI (body mass index, a ratio of weight to height).

But the bottom line may not be quite that simple. As an observational study, the results don’t show whether being overweight directly caused the deaths.

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Other Factors

The study did not separate out the premature death risk in women who had been overweight at 18 but lost their extra weight before joining the study.

Women who were overweight or obese as teens were more likely to be overweight at the start of the study, smoke cigarettes, drink greater amounts of alcohol, and avoid vigorous physical activity during adolescence.

Adjusting for those factors didn’t change the study’s results. Adult BMI didn’t totally explain the findings either, note van Dam and colleagues.

They caution that the results need to be confirmed in other groups, since most of the nurses were white and because self-reported data isn’t always accurate. For instance, the researchers found some underreporting of weight when they checked some of the nurses’ medical records.

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Second Opinion

The journal includes an editorial by the CDC’s William Dietz, MD, PhD. He didn’t work on van Dam’s study.

Dietz notes that “the reported effect of overweight on death has been controversial.” But he sees little argument about links between obesity and adult diseases such as diabetes and heart disease.

Losing extra weight may lower those risks, Dietz points out. For instance, he writes that losing 10 percent of body weight can help curb obesity-related high blood pressure, blood fat problems, and glucose (blood sugar) intolerance.

The best strategy, Dietz says, is to help kids avoid gaining extra weight in the first place. He offers these suggestions:

Parents should limit high-calorie foods and TV time for kids. Schools can restore physical education classes and offer healthy foods. Communities should boost access to recreational facilities.

If your teen years are long behind you, and you’re still carrying extra pounds, don’t despair. Your doctor can gauge your health and talk about changes that might improve it.

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By Miranda Hitti, reviewed by Louise Chang, MD

SOURCES: van Dam, R. Annals of Internal Medicine, July 18, 2006; vol 145: pp 91-97. Dietz, W. Annals of Internal Medicine, July 18, 2006; vol 145: pp 145-146. News release, Harvard School of Public Health.