Vitamin D-related genotype affects response to high-protein diet, insulin … – Healio
Adults with type 2 diabetes carrying the T allele of DHCR7, which affects vitamin D metabolism, are more likely to benefit from a high-protein weight-loss diet than those who do not carry the genetic variant, according to research in Diabetologia.
“People carrying genotypes determining different vitamin D levels may benefit [differently] by taking high-protein weight-loss diets in improving insulin resistance, which is related to high diabetes risk,” Lu Qi, MD, PhD, chair of the department of epidemiology at Tulane University in New Orleans, told Endocrine Today.
Qi, Qibin Qi, PhD, of Albert Einstein College of Medicine in New York, and colleagues analyzed data from 732 adults with overweight or obesity and available genotype data participating in the POUNDS Lost study, a randomized trial of adults assigned to one of four energy-limited diets for 2 years. The four diets were low protein, high protein, low fat and high fat. Researchers genotyped three variants — DHCR7 rs12785878, CYP2R1 rs10741657 and GC rs2282679 — that are related to vitamin D metabolism and assessed genotype effects on changes in body weight, fasting glucose level, insulin and homeostasis model assessment of insulin resistance (HOMA-IR) at 6 months (n = 656) and 2 years (n = 596).
In the high-protein diet group, researchers found the T allele of DHCR7 rs12785878 was associated with greater decreases in fasting insulin (P = .0009) and HOMA-IR (P = .002); there was no significant genotype effect in the low-protein diet group. After adjustment for age, sex, ethnicity and baseline value for the respective outcome trait, researchers found significant interactions between DHCR7 rs12785878 and both high- and low-protein diets in changes in fasting insulin and HOMA-IR at 6 months.
Researchers did not observe an interaction between the other two genetic variants and diet type on changes in blood glucose control.
“For overweight or obese patients, eating a low-calorie, high-protein diet may help lower diabetes risk,” Lu Qi said. “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.” – by Regina Schaffer
Disclosure: The researchers report no relevant financial disclosures.