Excess fat having a health-advancing influence is an oxymoron to almost everyone. But in some rare cases, abdominal obesity may not be a Type 2 diabetes risk factor at all due to specific genetic predispositions, according to a new study.
What Is Metabolically Healthy Obesity?
Scientists dug into the rare phenomenon of metabolically healthy obesity. The term refers to a condition where a person is obese based on their body mass index but does not exhibit the typical metabolic abnormalities often associated with obesity, including insulin resistance. They have relatively normal metabolic markers, suggesting a lower risk of obesity-related health complications like diabetes.
“There is a growing body of evidence for metabolically healthy obesity,” researcher Mete Civelik, who holds a doctorate in bioengineering and is an associate professor at the University of Virginia (UVA) School of Medicine, said in a press statement. “In our study, we found a genetic link that may explain how this occurs in certain individuals.”
Can Belly Fat Be Protective?
Researchers found that some people have genetic variants that predispose them to store fat in the abdominal region while simultaneously having a defensive effect against Type 2 diabetes.
However, the rarity of the variants makes the applicability of these findings to the general population unclear.
Within the extensive array of human genome regions that contribute to the buildup of visceral fat, five specific genes were found to exhibit a safeguarding influence against Type 2 diabetes, Yonathan Aberra, the lead author of the study and a doctoral candidate at UVA’s Department of Biomedical Engineering, a joint program of the School of Medicine and School of Engineering, said in a press release. This implies that these five genes seemingly encourage fat accumulation while concurrently providing protection against the development of the condition.
A specific genetic variation called rs6860588 may explain the unusual link. People with the “T” version of this variation tended to have more belly fat which didn’t increase their diabetes risk.
Expert Urges Caution
While the findings present intriguing possibilities, experts caution that more research is needed to quantify how prevalent these genetic variants are in the population and to further validate the results before challenging the large body of epidemiological evidence linking abdominal obesity to increased diabetes risk.
“There is strong epidemiological evidence that waist-to-height ratio, which is a proxy for central adiposity, can predispose to diabetes even in people whose weights are OK,” Margaret Ashwell, a British-based public health researcher and a consultant in nutrition science specializing in obesity and shape, told The Epoch Times.
The waist-to-height ratio compares waist circumference to height; ideally, waist circumference is less than half of height. “Fat stored in central depots is a risk factor for major metabolic diseases, such as Type 2 diabetes and heart disease” Ms. Ashwell added.
While the new study suggests some people may have genetic factors that protect them, it is not saying that central adiposity is not a risk factor for Type 2 diabetes in the general population, Ms. Ashwell said.
“The simple message of ‘keep your waist to less than half your height’ can be applied to men and women and children of all ages in all ethnic groups,” she said.