Monique van Nielen, PhD, from Wageningen University in the Netherlands, and colleagues examined the long-term association between total, animal and plant protein intake and the incidence of type 2 diabetes.
Data was collected from 12,403 patients with incident type 2 diabetes from the European Prospective Investigation into Cancer and Nutrition-InterAct case-cohort study, and a stratified subcohort of 16,154 individuals from eight European countries. Participants were followed for an average of 12 years.
The incidence of type 2 diabetes was increased for those with high intake of total protein (per 10 g: hazard ratio, 1.06; P<0.001 trend) and animal protein (per 10 g: HR, 1.05; P=0.001 for trend), the researchers found after adjusting for important diabetes risk factors and dietary factors.
The effect was modified by sex (P<0.001) and by body mass index among women (P< 0.001). The correlations were stronger among women, especially obese women with a BMI >30 kg/m² (per 10 g animal protein: HR, 1.19) and were not significant for men. There was no correlation between plant protein intake with type 2 diabetes (per 10 g: HR, 1.04; P=0.098 for trend).
“In view of the rapidly increasing prevalence of type 2 diabetes, limiting isoenergetic diets high in dietary proteins, particularly from animal sources, should be considered,” the researchers wrote.