Weight More Dominant than Genetics in Diabetes Risk

WEIGHT loss could prevent or even reverse diabetes, particularly in targeted populations at genetic risk of developing diabetes. Research presented at the European Society of Cardiology (ESC) Congress 2020 described a UK study assessing the impact of BMI compared to genetics for risk of developing diabetes. 

The UK study of 445,765 participants determined inherited risk of diabetes using 6.9 million genes and recorded height, weight, and BMI. Researchers then stratified participants into five groups according to genetic risk of diabetes, and into five groups according to BMI. Participants were 54% female, with an average age of 57.2 years. Average follow-up of participants was to age 65.2 years and during follow-up 31,298 developed Type 2 diabetes. 

Participants in the highest BMI group (average BMI: 34.5 kg/m2) had an 11-fold increased risk of diabetes compared with the lowest BMI group (average BMI: 21.7 kg/m2). Those in the highest BMI group had the greatest risk of developing diabetes of any group, including across all genetic risk groups. Statistical analysis was performed to assess risk of diabetes where high BMI was maintained over a greater period of time and found that the duration of high BMI did not impact risk of diabetes. Explaining the significance of this finding, Professor Brian FerenceUniversity of Cambridge, Cambridge, UK, and University of Milan, Milan, Italy said: “This suggests that when people cross a certain BMI threshold, their chances of diabetes go up and stay at that same high-risk level regardless of how long they are overweight.” 

Diabetes affected 463 million people worldwide in 2019, with 90% attributed to Type 2 diabetes mellitus cases. Since obesity is the main modifiable risk factor for diabetes, Prof Ference advocated targeting obesity in combatting diabetes: “It may also be possible to reverse diabetes by losing weight in the early stages before permanent damage occurs.” The study findings likely include individual variation in the BMI threshold that contribute to developing diabetes, as different people will develop abnormal blood sugar levels at different weights. Prof Ference explained the clinical message: “The findings indicate that most cases of diabetes could be avoided by keeping BMI below the cut-off which triggers abnormal blood sugar. This means that to prevent diabetes, both BMI and blood sugar should be assessed regularly. Efforts to lose weight are critical when a person starts to develop blood sugar problems.”