Free-range chicken eggs have at least 3X more vitamin D
Free-range farming: a natural alternative to produce vitamin D-enriched eggs
Nutrition
Julia Kühn, Dipl., Alexandra Schutkowski (Dr.), Holger Kluge (Dr.), Frank Hirche (Dr.),
Gabriele I. Stangl (Dr.) [email protected]
Institute of Agricultural and Nutritional Sciences, Martin-Luther-University Halle-Wittenberg, 06120 Halle (Saale), Germany
Objective: Food-based strategies need to be developed to improve the vitamin D status of individuals. Recent studies identified UVB irradiation as an efficient method to enrich mushrooms and eggs with vitamin D. These findings prompted us to test, whether free-range farming of hens could provide a valuable method to produce vitamin D-enriched eggs.
Methods: Laying hens were randomly assigned to three groups of 33/34 animals each, and were kept either indoors (indoor group), outdoors (outdoor group) or with an indoor/outdoor option (indoor/outdoor group) over 4 weeks.
Results: Here we show that the vitamin D3 content of egg yolk was 3- to 4-fold higher in the groups that were exposed to sunlight (outdoor group and indoor/outdoor group) compared to the indoor group (P<0.001). Egg yolk from the outdoor group revealed the highest vitamin D3 content which averaged 14.3 μg/100 g dry matter (DM), followed by that from the indoor/outdoor group (11.3 μg/100 g DM). Yolk from indoor eggs contained only 3.8 μg vitamin D/100 g DM. The 25(OH)D3 content of egg yolk was also influenced by sunlight exposure, although less pronounced than the vitamin D content (P<0.05). In contrast, free-range eggs randomly acquired from supermarkets had relatively low vitamin D contents.
Conclusion: Free-range farming offers an efficient alternative to fortify eggs with vitamin D, provided that the farming conditions are sufficiently attractive for the hens to range outside.
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See also Vitamin D Life
Vitamin D from animal increases 6X when consider that already processed by animal livers
200 IU per 100 gram of egg yoke when add vitamin D to poultry feed in Europe – Aug 2011
UVB on legs of chickens resulted in 70 IU vitamin D per egg yoke – July 2013
Hens with Vitamin D were better in at least 5 ways – RCT Aug 2018
Infant higher Vitamin D if mom took sun, took Vit D, was not obese, or ate eggs (China) – Feb 2019
Feed chicken lots of vitamin D, get 6000 IU per egg with no change in production – Nov 2013
Omega-3 from biofortified eggs is practical (and great for health) – Nov 2015
Add vitamin D to animal feed to fortify the resulting human food – Oct 2012
- Animal feed fortification is rarely permitted anywhere around the world
See also web
- Vitamin D Fortification of Eggs for Human Health Journal of the Science of Food and Agriculture, Oct 2013
- Depending on the dietary concentrations used, it was possible to produce eggs with between 200–700 iu vitamin D
- How do different eggs stack up in terms of flavor, nutrition and animal welfare? Mercola June 2019
- Description with video of differences between free run (indoors) < cage-free (indoors) < free range = pasture raised = organic