Weight Gain May Up Womens Heartburn

May 31, 2006 -- When women gain weight, they may raise their risk of developing heartburnheartburn, even if they don't gain a lot of weight and aren't already overweight or obese.

So says a study published in The New England Journal of Medicine.

"Even moderate weight gain among persons of normal weight may cause or exacerbate symptoms of reflux," write Brian Jacobson, MD, MPH, and colleagues. Jacobson works at Boston University's medical school and Boston Medical Center.

Jacobson's team created a questionnaire on gastroesophageal reflux disease (GERDGERD, often called heartburn). They sent the questionnaire to more then 10,000 women who took part in the Nurses' Health Study, a long-term study of women's health.

The results: 6,215 women -- 59% of those who took the survey -- reported GERD symptoms, most of which were mild or moderate. Those who had gained weight since age 18 were more likely to be in that group.

Jacobson and colleagues did a little time traveling for the study's sake.

Flash back to 1976. That's when the Nurses' Health Study started. Participants were 30 to 55 years old then.

In 1980, participants reported their weight when they were much younger -- 18 years old. They also reported their weight in 1998, when they were 52 to 77 years old.

Jacobson's team compared participants' self-reported weight at age 18 with their weight at age 52 to 77 years. They also calculated the women's BMI (body mass index), which relates height to weight.

Those who gained weight had greater odds of new or worsened GERD, the study shows. That pattern was seen for women with normal, overweight, and obese BMI.

Specifically, "an increase in BMI of more than 3.5, as compared with no weight changes, was associated with an increased risk of frequent symptoms of reflux," the researchers write.

What does that mean in real life? Let's say a woman was 5-feet 5-inches tall and weighed 125 pounds at age 18. That gives her a BMI of 20.8.

If that same woman later weighs 148 pounds, her BMI would have risen by over 3.5, assuming her height hadn't changed. But even at her heavier BMI of 24.6, her BMI would still fall short of the overweight BMI category, which starts at a BMI of 25.

Adjusting for other factors -- including dietary habits -- didn't change the study's results.

The findings support the theory that being overweight or obese is a risk factor for GERD, write Jacobson and colleagues. They add that since the study only included women, they can't say whether or not the results also apply to men.

The researchers can't be certain that the women reported their weight accurately. Jacobson's team also isn't sure which came first: women's weight gain or GERD.

SOURCES: Jacobson, B. The New England Journal of Medicine, June 1, 2006; vol 354: pp 2340-2348. WebMD Health Tools: "BMI Calculator."