An interventional study of Vitamin D3 bioenhanced eggs and 25(OH)D3 bioenhanced eggs in Healthy Adult Participants and Vitamin D Insufficiency, sponsored by Cornell University. Recruiting at 1 site in United States. Open to participants aged 18 Years to 40 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-10-05.
Sponsored by Cornell University · Not applicable, Interventional, and Basic science
The purpose of this research is to evaluate if 1) consumption of vitamin D3- or 25(OH)D3-biofortified eggs will increase vitamin D and 25(OH)D status in young adults who consume these bioenhanced eggs, 2) to determine if the gut microbiome profile is associated with 25(OH)D or vitamin D status and 3) to evaluate possible changes in the gut microbiome following an 8-week supplementation period providing 5(OH)D- or vitamin D bioenhanced eggs.
In the wintertime, decreased UVB exposure limits vitamin D synthesis. Vitamin D insufficiency is common in the US and globally, with insufficiency evident in 41% of US adults over the age of 18 years, and has been linked to several adverse health outcomes. While dairy products are the major source of dietary vitamin D intake for the US public, little attention has been placed on other animal products (meat or eggs) as a source of vitamin D3 and 25(OH)D3. Determining the bioavailability of vitamin D-fortified eggs can inform updated dietary guidelines.
Decreased 25(OH)D status has also been associated with a less diverse gut microbiome. Additionally, little attention has been given to how bioenhanced foods containing vitamin D3 or 25(OH)D3 may differentially shape the gut microbiome and thus human vitamin D metabolism. Prior research shows a strong correlation between 1,25(OH)2D3 concentration and gut microbial diversity in elderly men. Further research will help inform recommendations that address the efficacy of the form of vitamin D ingested from food products and how vitamin D status may shape the gut microbiota.
Cornell University is the lead sponsor of 96 studies on the registry; 18 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Dietary Supplement: Vitamin D3 bioenhanced eggs
Dietary Supplement: 25(OH)D3 bioenhanced eggs
Six vitamin D3-fortified eggs per week will be provided to participants to consume each week for 8 weeks
Six 25(OH)D3-fortified eggs will per week be provided to participants to consume each week for 8 weeks.
Vitamin D Status
Serum concentrations of vitamin D2, vitamin D3, 25(OH)D2, 25(OH)D3, 1,25(OH)2D2, 1,25(OH)2D3, 24,25(OH)2D3, and vitamin D binding protein concentration will be measured biweekly over 8 weeks to assess vitamin D and 25(OH)D bioavailability.
Time frame: Baseline, and time course of week 2, week 4, week 6, week 8
Gut microbiome composition
Fecal samples will be collected for metagenomic analyses to evaluate the impact of vitamin D or 25(OH)D status and intake on the gut microbiome.
Time frame: Baseline, week 4, week 8
Plan to share: No
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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