Health Discovery: Pay Attention to Waist-Hip Ratio

STUDY FINDINGS:

• In older people, waist size relative to hip size may be a more important measure of obesity than body mass index, which measures weight relative to height.

How big are your hips compared to your waist? It may be time to get out the tape measure because the answer could be important to your health, according to a new study.

For years, health experts have advised people to calculate their BMI, or body mass index, which measures weight relative to height. Now a study published in the July Annals of Epidemiology finds another set of numbers—the waist-hip ratio—might be a more revealing predictor of longer life.

The waist-hip ratio is a measure of waist size divided by hip size. World health officials say men have too much abdominal fat if their ratio is greater than 0.9. For women, the cutoff is 0.85. For inspiration, actresses Marilyn Monroe, Audrey Hepburn and Sophia Loren all had waist-hip ratios close to 0.7—clearly healthy figures.

The researchers in this study examined the BMI, the size of the waist and the waist size compared to the hip size in 1,189 men and women ages 70 to 79 during a 12-year period. They found that those with the largest waist-hip ratio had a higher risk of dying. So, for example, in a woman with a hip size of 40 inches, an increase in waist size from 32 to 36 inches meant a nearly 30 percent higher risk of death: the bigger the belly compared to the hips, the bigger the risk.

They found no such mortality link with waist size alone. And higher BMI numbers didn’t carry a larger risk either.

Preethi Srikanthan, an assistant professor at UCLA’s David Geffen School of Medicine said waist size relative to hip size is a better measure than BMI in older adults.

She said the waist-hip ratio might provide a better snapshot of late-life fitness by reflecting the extent of muscles in the hips and upper thighs, adding that keeping or developing good muscles later in life is as important as losing unwanted weight.

For the men in the study the risk of death jumped 75 percent once their waists grew wider than their hips. The study, however, was too small to isolate risk by specific groups, including gender, says Francisco Lopez-Jimenez, M.D., director of clinical practice at the Mayo Clinic’s Cardiovascular Health Clinic in Rochester, Minn. He also cautioned that the findings do not mean the scale can now be ignored. A growing waist-hip ratio has to be taken “very seriously,” he says, adding that a high waist-hip ratio may be telling you your muscle mass in legs and pelvis has gone down, while abdominal fat has increased.

Charlotte Huff is a health and business writer who lives in Fort Worth, Texas.