High-protein diet could improve weight loss and reduce insulin resistance in obese or overweight adults with type 2 diabetes

Adults with type 2 diabetes and a particular genotype will benefit more from a high-protein diet than people without the genotype, according to new research.
The study, conducted at Tulane University, New Orleans, found that the T allele of DHCR7, which affects how vitamin D is metabolised, leads to greater weight loss benefits from a high-protein diet.
“People carrying genotypes determining different levels may benefit by taking high-protein weight-loss diets in improving insulin resistance, which is related to high diabetes risk,” Lu Qi, chair of the department of epidemiology at Tulane University in New Orleans told Endocrine Today.
The researchers analysed data from 732 adults, all of whom were either overweight or obese. Each of them had been assigned to one of four diets: low protein, high protein, low fat or high fat. The researchers genotyped three variants that affect vitamin D metabolism: DHCR7, CYP2R1 and GC, then observed how each genotype affected body weight, fasting glucose level, insulin and insulin resistance.
The researchers found that, for those in the high-protein diet group, DHCR7 was linked to lower levels of fasting insulin and insulin resistance. There were no similar effects in any of the other diet group or genotype combinations.
Lu Qi said: “For overweight or obese patients, eating a low-calorie, high-protein diet may help lower diabetes risk. In diet intervention trials similar to our study, [it would be helpful] to study the changes of vitamin D levels and their impact on diabetes-related biomarkers among individuals carrying different genotypes of DHCR7 variant.”
The findings were published in Diabetologia.