Replacing Dietary Meat with Fish Increases Plasma Glucose without Affecting Protein Glycation

Western diets high in red meat are associated with hyperglycemia, which promotes insulin resistance and diabetes. Elevated plasma glucose promotes glycation of circulating proteins such as albumin, which is thought to lead to some of the complications associated with hyperglycemia. We hypothesized that lowering meat consumption would reduce protein glycation. Forty five healthy adult omnivorous subjects were randomized into one of three groups and instructed to either consume meat or poultry twice per day (control), eliminate meat and increase dietary fish (pesco‐vegetarian), or adopt a vegetarian diet (lacto‐vegetarian) for four weeks. Fasting plasma samples were collected from participants at baseline and after 4 weeks of the dietary intervention. Plasma glucose concentrations were measured using a commercially available kit. Percent glycated albumin was measured by mass spectrometry. Plasma glucose concentrations were significantly increased following 4‐weeks of pesco‐vegetarian diet (P=0.002, paired t‐test). Neither the lacto‐vegetarian (P=0.898) or the control diet (P=0.233) affected plasma glucose concentrations. Despite the significant increase in plasma glucose following a pesco‐vegetarian diet, no change in percent glycated albumin was observed (P>0.50, ANOVA). These findings may indicate a protective effect of the pesco‐vegetarian diet on protein glycation in the presence of elevated plasma glucose and suggest the need for additional studies to examine the link between increased fish consumption and glucose regulation.