Ensuring sufficient vitamin D intake through diet during lockdown
Vitamin D plays a key role in maintaining bone and muscle tissue and boosting our immune system. In the current COVID-19 epidemic, our immune defences might need to work particularly hard. We get our vitamin D intake from food sources such as oily fish, cheese and egg yolk. ANSES is reiterating the importance of ensuring sufficient intake, not only during the current lockdown but all year round, particularly for older people, people with olive or dark skin, and menopausal women. For these populations, an insufficient intake over a long period leads to weaker bones and a higher risk of fractures, as well as decreasing immune defences. The Agency has compiled a list of vitamin D-rich foods that you may already have in your cupboards or that you can add to your basket when next you go shopping.
Vitamin D deficiency increases the risk of fractures
Vitamin D is essential for our bodies to function effectively. We cover our daily vitamin D needs in two ways: by exposing our skin to sunlight or by eating foods that are rich in vitamin D. An inadequate intake of vitamin D can lead to reduced bone mass and hence a greater risk of fractures. These risks are particularly high where the level of physical activity is low, as may be the case during lockdown (link to opinion on maintaining physical activity in lockdown situations).
Eating two portions of fish a week, of which one portion of oily fish, contributes significantly to vitamin D intake
Vitamin D is found in a number of fatty foods. Even when not in lockdown, it is important to eat these foods regularly in order to meet the body’s needs.
Which foods are rich in vitamin D?
This vitamin is found primarily in:
- oily fish: herring, sardines, salmon and mackerel;
- offal (particularly liver);
- egg yolk;
- dairy products fortified with vitamin D;
- butter and margarine;
- cheese;
- unfortified milk (to a lesser degree);
- meat (to a lesser degree).
ANSES is reiterating the importance of eating a varied diet all year round, without forgetting sources of vitamin D. Eat fresh fish whenever you can. This is also a good time to clear out your cupboards: tinned fish, such as sardines, herrings and mackerel, are rich in vitamin D.
For more information on foods containing vitamin D: see the Ciqual table.
Older people, people with olive or dark skin, and menopausal women are at higher risk of poor bone health and reduced immunity
Some people are at higher risk of inadequate vitamin D intake. The lockdown may have an impact on their bone health, reducing bone density and increasing the risk of fractures.
ANSES is reiterating the importance of sufficient vitamin D intake through diet for people at risk: i.e. older people, people with olive or dark skin, who synthesise vitamin D less efficiently when exposed to the sun, and menopausal women, for whom hormonal disruption leads to greater bone demineralisation, increasing the risk of fractures.
Nevertheless, taking food supplements containing vitamin D may increase intake to excessive levels leading to hypercalcaemia – a build-up of calcium in the blood. This can result in tissue calcification, with consequences for the heart and kidneys.
The Agency reiterates that food supplements for offsetting a possible inadequate vitamin D intake should be taken only on dietary or medical advice, particularly as in most cases, you can get all the vitamin D you need through your diet and through exposure to the sun. You just need to make sure that you cover your requirements through these two methods.
Expose your skin to the sun for 15 minutes every day, from a garden, terrace, balcony or window.
If you are in lockdown at home, particularly if you do not have a garden, it is more difficult to synthesise vitamin D through exposure to sunlight. In the spring, exposing your hands, forearms and face to the sun every day for between 15 and 20 minutes, nevertheless provides you with the daily intake of vitamin D necessary to cover the needs of a healthy adult. If you do not have a garden, terrace or balcony, you can expose your skin to the sun from an open window, while taking precautions against any harmful effects (sunburn).