(P06-052-25) Bioavailability of 25-Hydroxyvitamin D3 From Intrinsically Labeled Eggs and Chicken

Objectives: Approximately 42% of U.S. adults are D insufficient [(25(OH)D < 20 ng/mL]. Biofortifying chicken and eggs with 25(OH)D3 may help improve D intakes. This study investigated if the consumption of 25(OH)D3 intrinsically enriched chicken and eggs can maintain or even improve D levels over the winter months.

Methods: Fifty-seven participants (22.6 ± 3.5 yr, 24 ± 2.8 kg/m2) completed an 8-week study [from January to March when endogenous production of 25(OH)D3 is limited] where they were randomized into three interventions: 25(OH)D3 enriched chicken and egg group (25D3), placebo group (P) ingesting control chicken and eggs, or D3 supplement group (D3) ingesting control chicken and eggs and a daily 1000 IU D3 supplement. Participants were given 1,500 g of 25(OH)D3 enriched or control chicken weekly (week 1-8), and five 25(OH)D3 enriched or control eggs were added per week from week 5-8. Blood was collected biweekly for assessment of D metabolites.

Results: Groups did not significantly differ in age, BMI, or 25(OH)D3 at baseline. At week 4, 25(OH)D3 concentrations were increased (27.0 ± 8.3 vs. 30.2 ± 6.6 ng/mL, p<0.05) in the D3 group (n=19, ingesting an average of 6658 ± 1571 IU of vitamin D3 weekly). In contrast, no significant change in 25(OH)D3 was evident (28.7 ± 9.2 vs. 26.0 ± 10.2 ng/mL) across this time interval in the 25D3 group (n=19, ingesting an average of 3258 ± 516 IU of 25(OH)D3 per week). Participants in the P group (n=19) exhibited a decrease in 25(OH)D3 levels (24.0 ± 8.3 vs. 20.9 ± 7.8 ng/mL, p<0.05). Between visits 5 and 8, subjects were provided 5 eggs/week providing a mean of 560 ± 138 IU/week, 207 ± 41 IU/week or 210 ± 37 IU/week in the 25D3, P, or D3 group respectively. At week 8, mean serum 25(OH)D3 concentration (32.5 ± 8.1 ng/mL) in the D3 group was higher when compared to the 25D3 group (25.5 ± 9.9 ng/mL, p<0.05) or the P group (19.7 ± 6.7 ng/mL, p<0.05). At week 8, 47% of participants in the P group were vitamin D insufficient ( < 20 ng/mL) compared to only 11% of participants in the 25D3 group and 0% of participants in the D3 group (Fisher’s Exact Test for Count Data, p<0.01).

Conclusions: Consumption of 25(OH)D3 enriched poultry meat and eggs helped protect against the seasonal decline in serum 25(OH)D3, but additional studies are needed to investigate the effects of 25D3 biofortified poultry products on 25(OH)D3 status and related health outcomes.

Funding Sources: The US Department of Agriculture, USDA-2019-67021-29945