By George Citroner
Upending conventional wisdom, a new study has found that there is no one-size-fits-all, healthy BMI range for people living with Type 2 diabetes.
Rather, the research reveals a twist—a person’s optimal body weight actually shifts as they grow older.
Surprising Finding
Upcoming research to be unveiled at the European Obesity Congress in Venice next month sheds new light on the ideal body weight range for adults with Type 2 diabetes to reduce their risk of dying from cardiovascular disease.
The study, based on health data from the UK Biobank, a biomedical database available to the public that contains genetic, health, and behavioral information on about 500,000 people, followed 22,874 participants with the condition for nearly 13 years, tracking their cardiovascular health.
The researchers examined the data by dividing participants into two age cohorts—those over 65 (the elderly) and those aged 65 or younger (the middle-aged). They then assessed how factors like body mass index (BMI), waist circumference, and waist-to-height ratio correlated with the risk of cardiovascular death in each age group.
For adults 65 and younger, the findings suggest that people in this age group who were overweight showed a 13 percent increased risk of cardiovascular mortality than those who maintained a normal BMI, which is between 18.5 and 24.9.
However, the trend reversed for those over 65. In this older group, people who were moderately overweight had the lowest risk, experiencing an 18 percent lower risk of cardiovascular death compared to their normal-weight peers.
The researchers also found a positive correlation between waist circumference, waist-to-height ratio, and cardiovascular mortality risk. As waist circumference increased, so did the risk of cardiovascular death. This trend held true regardless of age, with similar patterns observed for waist-to-height ratio. However, no significant BMI thresholds were identified.
Experts Weigh In
“Importantly, we demonstrate that optimal BMI for people with type 2 diabetes varies by age, independent of traditional cardiometabolic risk factors,” Dr. Shaoyong Xu from Xiangyang Central Hospital, and lead author of the study, said in a statement. “Our findings suggest that for older individuals who are moderately overweight but not obese, maintaining rather than losing weight may be a more practical way of reducing their risk of dying from cardiovascular disease,” he added.
The results are “very difficult to interpret and draw conclusions from,” Dr. Theodore Strange, chair of medicine at Staten Island University Hospital in New York, told The Epoch Times, as it is an observational study and no causes could be identified.
The researchers could not determine why being overweight was protective for older diabetics. The findings may not apply to people from non-white ethnic backgrounds, as the UK Biobank cohort was predominantly white, they noted.
A small amount of excess weight in the elderly could indicate better nutritional status and prevent frailty, Dr. Strange said. “But this has never been shown in an evidenced-based study.”
Continued evaluation of this significant research is important to help the growing population of older adults with diabetes live healthier, higher-quality lives, he added.
The ‘Obesity Paradox’
The phenomenon described in the study falls under what is commonly known as the “obesity paradox,” Dr. Shiara Ortiz-Pujols, an obesity medicine specialist at Staten Island University Hospital in New York, told The Epoch Times.
The obesity paradox refers to counterintuitive findings suggesting that while people with overweight or obesity are at higher risk of developing heart problems, those with existing heart conditions who are overweight or obese tend to have better outcomes and lower mortality rates than their normal-weight counterparts.
The science behind BMI remains contentious. The American Medical Association has acknowledged the metric’s significant limitations and has encouraged doctors to not rely on BMI alone when diagnosing obesity.
BMI, the primary factor used to assess risk in this study, fails to account for important factors like body composition, gender differences, fat distribution, and muscle mass, Dr. Ortiz-Pujols said.
Also, she added, BMI does not adequately reflect the changes that occur with aging, including:
- Greater fat accumulation
- Loss in lean muscle mass
- Increased frailty and reduced exercise capacity
- Higher risk of malnutrition
- Greater risk of cachexia, an unintentional weight and muscle loss associated with chronic diseases, including heart failure
Focusing on BMI as the sole indicator of morbidity and mortality risk, particularly in the elderly, provides an incomplete understanding of why older adults with obesity may have a lower risk of adverse health outcomes, Dr. Ortiz-Pujols said. This oversight fails to capture the nuances of how body composition and aging-related changes can impact health.
