Consumption of 12 eggs per week for 1 year increases serum zeaxanthin concentrations but not other major carotenoids, tocopherols, and retinol in humans (645.25)

Abstract

Previous work has shown that egg yolk consumption yields increase bioavailability of lutein and zeaxanthin compared to dietary supplements. However, little is known of the effects of an egg‐rich diet on serum levels of the other carotenoids, vitamin A and vitamin E. This study investigated how a diet of 12 eggs per week for 1 year influenced serum carotenoid, tocopherol, and retinol concentrations in adults. A group of 45 adults were placed into either the intervention group (n=27; consumed 12 eggs per week for 12 months) or control group (n=18; consumed no eggs or high egg products for 12 months) after 6 weeks of an egg‐free diet. Serum carotenoid and vitamin concentrations were measured by high performance liquid chromatography (HPLC) at baseline and 12 months. Seven day diet records were collected and analyzed on a monthly basis to help ensure the egg consumption protocol. Results showed that the intervention group demonstrated a statistically significant increase (83%) in serum zeaxanthin concentrations after 12 months. A notable, but not statistically significant, increase in serum lutein concentration was also observed in the intervention group (52%) after 12 months. Although serum alpha‐carotene concentration did not change in the intervention group, it significantly increased in the control group (18%) after 12 months. No other serum carotenoid, retinol, or alpha‐ or gamma‐tocopherol concentrations changed significantly during the 12 months. The findings of this study suggest that egg yolk consumption does not significantly alter the serum concentrations of tocopherols, retinol, and carotenoids other than alpha‐carotene and zeaxanthin.Grant Funding Source: Supported by the Egg Nutrition Center