According to a new study that will be presented today (Saturday 21 May at 12:00 noon CEST) at the
24th European Congress of Endocrinology in Milan, Italy on vitamin D food fortification working better with
water and milk than in juice. By measuring the maximum concentration over time, the researchers found
bioavailability of vitamin D to be higher in milk and water.
Vitamin D insufficiency is a global health problem
Vitamin D insufficiency has been linked with multiple health issues, including the immune response to COVID-
191. Estimates show that as much as 40% of the European population could be suffering from vitamin D
deficiencies, with 13% potentially suffering from severe vitamin D deficiency2. Vitamin D supplements are
therefore vital – and knowing whether they will be absorbed and how best to aid absorption is crucial.
To answer this question, Dr. Rasmus Espersen of Aarhus University in Denmark and his colleagues
conducted a randomised trial on 30 postmenopausal women aged 60-80 with vitamin D deficiency. The study
aimed to measure immediate changes in blood concentrations in response to the consumption of various
food items containing 200 g D3. In a random order, 500 mL of water, milk, juice, juice with vitamin D bound
to whey protein isolate as well as 500 mL of water without vitamin D (placebo) were presented to the study
participants. Blood samples were collected at 0h, 2h, 4h, 6h, 8h, 10h, 12h, and 24h on each study day.
"One aspect that surprised me was the fact that the results seen in the water and milk groups were equal.
This was quite unexpected given the fact that milk contains more fat than water." stated Dr. Espersen.
The study revealed that whey protein isolate in apple juice did not enhance maximum concentration of D3
compared to juice without WPI. However, compared to juice, D3 concentrations were significantly higher in
response to intake of milk and water. No difference was observed between milk and water. Therefore, the
conclusion from this study is that vitamin D fortification works better in water or milk than in juice.
1 Bilezikian et al., (2020), MECHANISMS IN ENDOCRINOLOGY: Vitamin D and COVID-19, European Journal of
Endocrinology, Volume 183:5, https://doi.org/10.1530/EJE-20-0665
2 Amrein et al., (2020), Vitamin D deficiency 2.0: an update on the current status worldwide, European Journal of
Clinical Nutrition, Volume 74, pp 1498-1513, https://www.nature.com/articles/s41430-020-0558-y#Sec23
European Society of Endocrinology
