In ODIN, scientists are partnering with large and small food companies to explore new technologies and develop a range of staple foods with increased vitamin D content which are aimed at preventing vitamin D deficiency. These vitamin D-enhanced foods include meat, fish, cheese, eggs, bread, and mushrooms, which are of critical importance as consumed by many in the population.
Vitamin D in meat and eggs
In animal feeding trials in ODIN, vitamin D bio-fortified pork, beef and hen’s eggs are being produced by enhancing the vitamin D2 or D3 content of animal feeds, or by using simulated sunshine exposure experiments, to increase the vitamin D content of meat and eggs for the European consumer.
We have recently published the results from a dietary intervention (EnhanceD study) in which healthy adults consumed vitamin D enhanced eggs either as 7 vitamin D3- or 7 25 hydroxyvitamin D3-enhanced eggs or ≤ 2 commercially available eggs per week (control group, in which vitamin D status was expected to decline) for 8 weeks during wintertime. The vitamin D3- and 25 hydroxyvitamin D3-enhanced eggs were produced by providing hens with feed containing either vitamin D3 or 25 hydroxyvitamin D3 at the maximum allowable content. Overall, this randomised controlled trial showed that consumption of 7 vitamin D3- or 25 hydroxyvitamin D3-enhanced eggs, both of which were found to be acceptable to consumers, maintained serum 25 hydroxyvitamin D concentrations (best indicator of vitamin D status) and protected against its decline during the 8 weeks of winter. To read a summary of these findings or to access the full publication, click on the tabs on the left hand side of this page.
Vitamin D in fish
We are carrying out fish-feeding studies in which the vitamin D content of farmed salmon, sea bream and trout for human consumption is being increased by fortifying feedstuff with vitamin D3 in different formats and levels, including vitamin D3-enhanced microalgae as a potential natural way of bio-fortifying fresh and seawater fish.
Vitamin D in low-fat cheese
We conducted a human dietary intervention study in which postmenopausal women consumed a reduced-fat, Gouda-type cheese, either unfortified or fortified with vitamin D3, to test the potential of this vitamin D fortified, low-fat cheese to prevent vitamin D deficiency during winter. Overall, this 8-week randomised controlled trial showed that consumption of vitamin D3-enriched cheese was effective in increasing mean serum 25 hydroxyvitamin D concentration (best indicator of vitamin D status) and in counteracting vitamin D deficiency during winter months in postmenopausal women in Greece. To read a summary of these findings or to access the full publication, click on the tabs on the left hand side of this page.
Vitamin D in vegetable foods
Using new human dietary intervention studies as well as existing data from previous human studies, we will provide answers on whether ultraviolet (UV) light irradiation can be used as a method to enhance vitamin D2 content of vegetable foods such as baker’s yeast for bread-making, mushrooms, and a powdered mushroom food ingredient.
ODIN has published the results of a human dietary intervention (BreaD study) in which the bioavailability of vitamin D2 from UV-irradiated yeast present in bread was investigated in an 8-week randomised controlled trial in healthy young adult women in winter. Overall the results of this study showed that consumption of the UV yeast-vitamin D2 fortified bread did not affect serum 25 hydroxyvitamin D concentration (best indicator of vitamin D status). This new data suggests that vitamin D2 from UV-irradiated yeast in bread, despite being present post baking, was not bioavailable to humans. To read a summary of these findings or to access the full publication, click on the associated tabs on the left hand side of this page.
To answer the question as to whether UV-treated mushrooms can improve vitamin D status in European consumers, scientists in ODIN undertook a re-analysis of stored serum samples from a key randomised controlled trial and combined the findings with results from existing human studies to give greater statistical power and a more robust overall result than would be possible from any individual study (this is called a meta-analysis). Overall this ODIN work suggests that consumption of UV-exposed mushrooms may increase serum total 25 hydroxyvitamin D (best indicator of vitamin D status) when baseline vitamin D status is low. This is of relevance for Europe, particularly in winter when vitamin D status is low for many populations. To read a summary of these findings or to access the full publication, click on the relevant tabs on the left hand side of this page.
Proof of effectiveness of these new foods
Importantly, the proof of effectiveness of these new foods to increase vitamin D status is being individually investigated in separate human intervention studies as mentioned above, but also a range of these products is being simultaneously tested in a study of women at increased risk of vitamin D deficiency.
Dietary modelling of vitamin D intakes
Using food analytical data on the vitamin D composition of these new products and dietary survey data in a range of countries, we will conduct dietary modelling studies in ODIN to investigate the ability of these bio-fortification and tradition fortification strategies to increase vitamin D intakes across the population distribution for Europe.
This approach represents the best chance to develop inclusive food strategies designed to benefit food consumers across all life-stage, ethnic and gender subgroups.