The good news A loss of just 11 pounds cuts your risk of developing knee osteoarthritis by 50 percent. “You don’t have to lose a huge amount of weight to reap benefits,” Felson says.
Culprit No. 3
PRESSURE ON THE TUMMY
Obese women are the most prone to GERD, or gastroesophageal reflux disease, in which stomach acids back up into the esophagus, known as acid regurgitation, and cause heartburn. But now scientists have linked it to the over-weight too. A study of more than 10,000 women reported in The New England Journal of Medicine found that relatively small weight gains increased the risk: Among women with a baseline BMI of 25 or less, GERD in-creased 1.13 times if their BMI increased by just 0.5 to 1.5 units. For women who increased their BMI by 3.5 units, say from 24 to 27.5, their likelihood of having more frequent GERD symptoms grew nearly three times.
“There is a linear relationship between GERD and body mass index, and the more weight you gain, even if it is a moderate amount, the more problems you have,” says lead study author Brian Jacobson, MD, assistant professor of medicine at the Boston University School of Medicine.
The good news “It doesn’t take a lot of weight loss to reduce symptoms,” Jacobson says. Women who reduced their BMI value by 3.5 units, say from 27.1 to 23.6, experienced a 40 percent reduction in symptoms. While no one knows exactly how weight affects acid reflux symptoms, one theory is that extra fat around the middle increases stomach pressure, causing fluids to back up into the esophagus.
Culprit No. 4
Belly fat appears to be a risk factor for dementia. Scientists from Kaiser Permanente’s Division of Research recruited more than 6,500 men and women in northern California and measured their abdominal fat when they were ages 40 to 45. Then, 35 years later, researchers looked at the occurrence of dementia in the group. “What we saw was that a bigger belly was bad news,” says research scientist Rachel Whitmer, PhD, lead author of the Kaiser report.
The study, published in the journal Neurology last year, determined that dementia risk was 2.3 times greater for men and women who were overweight with a belly bulge than for those with a normal weight and waist size. People of normal weight but with excess belly fat had a 1.89 times higher risk of getting dementia than those of normal weight and no excess belly fat. “Excess weight is an issue, but where you carry it may be a bigger issue,” Whitmer says.
Although it’s not completely understood why belly fat may attack the brain, some animal studies have linked extra leptin, an appetite-control hormone made by belly fat cells, to diminished cognitive function. The hormone
may also be a player in the process of forming plaque in areas of the brain that control memory and thinking, Whitmer says. No study so far, however, has tested whether losing weight now reduces your risk of dementia later.
Culprit No. 5
A major study on breast cancer and weight found that women who gained 22 pounds after age 18 increased their risk of breast cancer by 18 percent. Researchers speculate that the connection may happen because after menopause, most of a woman’s estrogen comes from fat tissue. Therefore, having more fat increases the amount of estrogen in the body, which raises the risk of breast cancer. “It’s clear that there’s a correlation between weight gain and breast cancer development, and between weight gain and poorer outcomes after cancer treatments,” says medical oncologist Jennifer Griggs, MD, associate professor of medicine at the Uni-versity of Michigan, Ann Arbor. But will losing weight lower your risk of developing breast cancer? While no one knows for sure, it certainly can’t hurt, Griggs says.
THE BOTTOM LINE
Yes, the odds are stacked against you whether you want to lose weight or just maintain your current size. By midlife, your metabolism is slowing down, and your lean muscle mass (which burns more calories than fat tissue) is on the decline.