The middle of winter when sun exposure is limited is a good time for everyone to pay attention to getting enough vitamin D from food sources. This is particularly important for individuals living with diabetes, since there is preliminary evidence that vitamin D status is compromised due to secondary effects of diabetes.
Researchers at Iowa State University wanted to evaluate the effects of a food-rich source of vitamin D versus synthetic vitamin D on risk markers for diabetes. They started by studying rats genetically prone to develop obesity and type 2 diabetes (called Zucker rats) to determine whether vitamin D status was lower and more importantly, could be improved through simple addition of whole eggs in the diet. Eggs served as a quality source of protein and provided an active form of vitamin D (25D).
Here is what they found:
- The diabetic rats showed a marked increase in circulating vitamin D concentrations with the egg-based diet (148% higher than diabetic rats in the non-egg group), as did the lean control rats (a two-fold increase versus the non-egg group).
But there were benefits observed beyond vitamin D status. Keep in mind that Zucker rats are both obese and have diabetic related metabolic risk factors, like elevated blood glucose.
- Although still elevated, the whole egg diet reduced (by half) blood glucose and triglyceride levels in the obese diabetic rats. Whole eggs in diet also resulted in decreased weight gain.
This research team noted the following:
“This proof of principle study clearly demonstrated that whole egg consumption clearly results in increased plasma 25D concentrations, attenuated hyperglycemia and hypertriglyceridemia, as well as reduced weight gain in T2D [type 2 diabetes] rats.”
“Because whole egg is a natural food source of 25D, it represents an ideal dietary strategy to maintain vitamin D homeostatis in T2D…”
Future research to expand on this proof of principle study can help determine how much egg per day provides benefit and whether improving vitamin D status improves specific health outcomes associated with diabetes.
Click here for more information describing this research from the Iowa State University.
Jones, SK, GY Koh, MJ Rowling, and KL Schalinske. “Whole egg consumption prevents diminished serum 25-hydroxycholecalciferol concentrations in Type 2 Diabetic rats.” J Agric Food Chem 2016;64:120-124. This study was supported in part by the Egg Nutrition Center.