Will a Higher BMI Protect You After 65?

A soon-to-be-released study suggests older adults with overweight may have a lower heart disease mortality risk.

At the upcoming European Congress on Obesity in May, researchers will present an observational study that found the upper end of a normal BMI range (23–25 kg/m²) was linked to the lowest risk of dying from cardiovascular disease—but only to a point. Once subjects passed the age of 65, people considered moderately overweight (26–28 kg/m²) were the least likely to die of heart disease.

The study, which used U.K. Biobank data for 22,874 adults already diagnosed with type 2 diabetes from 2006 to 2010, found that for people in middle age, a BMI in the overweight range was linked to a higher risk of cardiovascular death by 13%. However, in adults over the age of 65, an overweight BMI was correlated with an 18% lower risk of death than among patients of the same age with a normal BMI.

At face value, the study seems to indicate that higher weight may provide a protective element later in life, but endocrinologists and geriatricians caution that BMI is an imperfect metric that ignores body composition. The study also tracked waist circumference and waist-to-height ratio, demonstrating that higher numbers in both measurements directly correlated to a higher risk of cardiovascular death across all age groups.

BMI Doesn’t Tell the Whole Story

Tonia Vinton, MD, medical director at UT Southwestern Medical Center, specializes in weight management and preventative medicine. She told Verywell that the BMI formula excludes information that can be very telling.

“Folks who have the disease of obesity usually have an excess of fat and a loss of lean muscle mass at the same time,” Vinton said. In older adults who are already losing muscle mass with age, this confluence may be diagnosed as sarcopenic obesity.

Sarcopenia is a loss of functional skeletal muscle mass and strength. The condition is age-related, but muscle loss begins in the 30s. As fat mass peaks between age 60 and 70 and replaces lost muscle mass, sarcopenic obesity can occur.

“What they’re saying in this meta-analysis is that sarcopenic obesity later in life may suggest that this person is actually aging a little slower,” Vinton said. It’s not that higher BMI is necessarily better; it’s that people who don’t experience sarcopenia until after age 65 are hanging onto muscle mass longer, delaying aging and heart disease.

Since BMI doesn’t take into account body composition, it’s difficult to pinpoint a reason for the lower risk of death seen in the study, which study authors acknowledged. If BMI is higher because of muscle mass as opposed to fat, that’s a good thing.

The study was also comprised primarily of White women and may not be indicative of other ethnicities. Vinton said BMI standards in the United States are primarily based on White subjects and differ for other ethnicities, rendering the study insights inconclusive for a broader audience.

Watch the Waist Measurements

The study showed that a higher waist circumference and waist-to-height ratio indicated a greater chance of cardiovascular-related deaths regardless of age. This implies that higher body fat, especially visceral fat, is detrimental no matter what.

Tina Sadarangani, PhD, RN, assistant professor at New York University and creator of CareMobi at The Enlightened Caregiver, says that some extra weight can reduce the risk of osteoporosis and can act as a “reserve” in the case of serious illness.

“That said, too much extra weight, especially in the midsection, can increase the risk of cardiovascular disease and also place extra strain on our joints,” Sadarangani told Verywell via email.

Vinton agrees, adding that the focus should be on weight training to build functional muscle mass.

“I think the takeaway is let’s be strong,” Vinton says. “We’re very centered on numbers as a culture, but that’s not a very healthy goal. It’s much more important to have high functionality as we age.”