High animal protein intake increases risk for Type 2 diabetes in the elderly
MedWire News: Results from a Greek study show that a high intake of animal protein is associated with an increased risk for Type 2 diabetes in an elderly population, whereas plant protein intake may have a protective effect.
Demosthenes Panagiotakos (Harokopio University, Athens, Greece) and colleagues enrolled 1190 men and women aged 65-100 years between 2005 and 2007 to take part in The Mediterranean Islands (MEDIS) study. In total, 260 were diabetic and 930 nondiabetic.
The researchers assessed the impact of different dietary intakes on the incidence of Type 2 diabetes using a semiquantitative food frequency questionnaire and food composition tables. Diabetes was defined as having a fasting blood glucose level of 125 mg/dl or above.
Following adjustment for age, gender, history of hypertension or hypercholesterolemia, obesity, and dietary habits, the team found that a 5% increase in meat and meat protein products or total protein intake was associated with a significant 34% and 29% increased relative risk for Type 2 diabetes, respectively.
Diabetic patients obtained 4.8% of their total energy intake from meat and meat protein compared with only 4.4% in the nondiabetic group.
Plant protein intake, in contrast, did not significantly influence risk for Type 2 diabetes in this study cohort, but the researchers believe it may have a protective effect.
"A possible pathophysiological explanation for the role of protein intake on glycemic-control indices and consequently, diabetes prevalence, is that high protein intakes, especially from red meat, contain certain types of preservatives, additives and other chemicals related to meat preservation, packaging, and processing," write the authors.
"The compounds that are most associated with the pathogenesis of diabetes are nitrates and nitrites, which are added in meat processing, as well as a variety of heterocyclic amines and polycyclic aromatic hydrocarbons formed in red meat, especially when cooked to 'welldone'. These compounds can be converted to N-nitrosamines, which are toxic to pancreatic beta cells."
The results of this study are published in the journal Diabetes and Metabolism.
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By Helen Albert