A study published by the University of Eastern Finland in The Journal of Clinical Endocrinology & Metabolism has established that a healthy diet combined with regular exercise is likely to lower the risk of type 2 diabetes by a high degree, even in people who have a genetic predisposition.
Type 2 diabetes is an emerging global health concern, and the International Diabetes Federation has estimated that one in eleven adults has this disorder, with 90% of the cases attributable to type 2 diabetes. In the United States alone, the CDC estimated that 38.4 million people had diabetes in 2021, including 38.1 million adults. Of those, 8.7 million adults were undiagnosed. It is therefore much-needed to look for more effective ways of prevention.
While more than 500 genetic variants that predispose to a higher risk of developing type 2 diabetes have been identified, it is also evident that major risk factors include physical inactivity, low intake of dietary fiber, high intake of saturated fat, and overweight. It has already been shown that lifestyle changes may prevent the onset of type 2 diabetes, but it was not known whether people at high genetic risk would also benefit from these changes.
The T2D-GENE trial was a three-year lifestyle intervention study involving nearly 1,000 men aged 50 to 75 in eastern Finland, all of whom had raised fasting glucose at baseline. More than 600 men took part in the intervention group, which received guidance on health-promoting lifestyles through group meetings and a dedicated web portal. Seventy-six single nucleotide polymorphisms, indicating a higher risk of type 2 diabetes, were used to rank each participant as high or low genetic risk. Chiefly, in the course of the study, the participants and researchers were unaware of the genetic risk group to which a participant had been assigned.
The participants in the lifestyle intervention group were able to make considerable improvements in their diets: they increased their intake of dietary fiber, improved the quality of fats consumed, and boosted their intake of vegetables, fruits, and berries. Many had a weight reduction, even though this was not an explicit objective. They did retain their already high levels of physical activity throughout.
Lifestyle changes were seen to help the deterioration of glucose metabolism, hence a quite low prevalence of type 2 diabetes in the intervention group relative to the control. These benefits were equally vital for individuals regardless of their genetic risk.
“These findings encourage everyone to make health-promoting lifestyle changes,” states Docent Maria Lankinen of UEF, a lecturer and first author of the study. She stressed that group and internet-based lifestyle guidance is an effective way to save healthcare resources.
It should serve as a reminder that an overall healthy lifestyle really can make a difference in people who are genetically predisposed to type 2 diabetes. This research turns the spotlight on diet and exercise as ways to prevent disease, interventions that could be scaled up and scaled down in a much more resource-efficient way if taken seriously enough in maintaining public health.