Whole egg protein markedly increases blood vitamin D concentrations in male Sprague‐Dawley rats (1041.9)

Diabetes is characterized by altered methyl group and vitamin D metabolism; aberrations that may play a role in cardiovascular disease and other co‐morbidities. Whole eggs are a rich source of nutrients such as choline, vitamin B6, vitamin B12, and sulfur amino acids that can optimize methyl group metabolism. Egg yolks also are a natural source of vitamin D, which may help to elevate circulating vitamin D (25‐OH‐vitamin D) concentrations. To date, the impact of whole egg consumption on methyl group metabolism and vitamin D balance has not been explored in a rat model. Eighteen male Sprague‐Dawley rats were fed three diets formulated to contain 20% protein from casein (control), egg white, or lyophilized whole egg for 6 wks. Blood, liver, kidney, and urine samples were obtained for analysis. Both the egg white protein and whole egg groups exhibited a trend (p= 0.07) for elevated activity of hepatic glycine N‐methyltransferase, a key regulatory enzyme in methyl group metabolism that is disrupted in a diabetic state. Although there was no difference in circulating 25‐OH‐vitamin D concentrations between the control and egg white protein diets, the whole egg diet resulted in a 4‐fold increase. This finding may be important in diabetes as urinary loss of 25‐OH‐vitamin D is elevated. These results suggest that whole egg consumption could be a viable approach to enhancing vitamin D status and optimizing methyl group metabolism. Grant Funding Source : Supported by Egg Nutrition Center