Vitamin D: Only these foods provide us with the vitamin

Even those who eat consciously will unfortunately find - it is not so easy to get enough vitamin D. Because the selection of vitamin D-rich foods is quite limited. Moreover, they usually contain only small amounts of the vitamin. But why is vitamin D so important for us?

The "Sun" Vitamin D

Vitamin D is a special vitamin: the body can produce it itself through the skin. However, sufficient sunlight is required for this. Only from April to September, the sun is high enough for adequate UVB radiation to reach our skin and stimulate the production of vitamin D. In people who regularly spend time outdoors, the skin produces 80-90 percent of the required amount. However, in autumn, the body's own production of vitamin D comes to a halt. Therefore, it is important to supply the body with sufficient vitamin D during the dark season. This is done through the body's own stores and additionally through food.

Vitamin D - important for the immune system and bones

Vitamin D is important for bone formation, teeth, and cell growth. It regulates the calcium and phosphate metabolism, thereby promoting the mineralization and hardening of bones. This vitamin reduces the risk of falls and fractures in older people. In children, it prevents rickets (softening of the bones). Vitamin D also plays an important role in immune defense against infections.

Only one out of ten women gets enough Vitamin D

Unfortunately, a total of 82 percent of men and 91 percent of women do not reach the recommended intake of vitamin D. This alarming assessment from the National Nutrition Survey II still holds true. The situation is even worse for adolescents and seniors in terms of their vitamin D supply.

Vitamin D: These 8 foods provide the most

• Eel (90 µg/100g)

• Salmon (16 µg/100g)

• Sardines (11 µg/100 g)

• Tuna (6 µg/100g)

• Trout (4 µg/100g)

• Eggs (3 µg/100 g)

• Porcini mushrooms (approx. 3 µg/100 g)

• Mushrooms (approx. 2 µg/100g)

• Dairy products such as milk and butter contain only traces of the vitamin.

• Avocado and dandelion do not contain vitamin D, despite often claimed

Mushrooms: Not always a good source of vitamin D

Among plant-based foods, mushrooms can be an optimal source with a high content of vitamin D. The emphasis here is on "can". Because, just like humans, mushrooms produce vitamin D when exposed to sunlight.

However, since mushrooms can thrive without daylight, they are usually grown in dark rooms. Mushrooms from the supermarket therefore probably provide less vitamin D than expected. The good news is that even after harvesting, mushrooms can still produce vitamin D (Ko Ja et al., 2008). Store-bought mushrooms, such as champignons, can be enriched with vitamin D at home by placing them directly in the sun for some time. Once the vitamin is formed, it remains stable for months. It is important to note that the synthesis of vitamin D in mushrooms is stimulated by UVB radiation. Windows do not let the sun's UVB rays through, so let the mushrooms "soak up" the sun by placing them near an open window or directly outside. This works wonderfully in spring and summer. Unfortunately, the UVB radiation is too weak in autumn and winter for this purpose. However, you can easily dry mushrooms in the sun during summer to have a supply for the rest of the year.

Animal foods high in vitamin D: fish and eggs

Among animal foods, it is primarily fatty fish from the sea that provide a lot of vitamin D, such as eel, salmon, or sardines. Eggs are also a good source of vitamin D, but only the yolk. In the past, cod liver oil was considered a proven source of vitamin D, much to the dismay of many children.

How much vitamin D do we need

The German Nutrition Society (DGE) recommends that children, adolescents, and adults should consume 20 µg of vitamin D (800 I.U.) daily through food. These are estimated values that secure the vitamin D requirement in the absence of endogenous production. However, there are no universally applicable recommendations for the daily vitamin D requirement. This is because it varies individually how much vitamin D each person produces. Various factors come into play: place of residence and sun exposure, lifestyle, skin type, and age are relevant. For medical reasons, higher vitamin D intake may be necessary, but always in consultation with your primary care physician, as side effects such as kidney stones or kidney calcification can occur with a regular intake of over 100 micrograms of vitamin D (4000 I.U.).

Additional vitamin D can be beneficial

But children and teenagers can also be affected by vitamin D deficiency - even in summer: Instead of playing outside and soaking up the sun, many spend their free time on a computer or game console. In summer, a lot of sunscreen can inhibit vitamin production.

Among the risk groups are also chronically ill people, as well as office workers and shift workers. Because they all spend too little time in the sun, and the body cannot produce enough vitamin D.

Vitamin D plays a key role in our health. Especially seniors and people who spend most of the day indoors should pay attention to an adequate intake of vitamin D. If this cannot be achieved through vitamin D-rich foods such as fish or eggs, a dietary supplement in consultation with a doctor may be advisable. It doesn't necessarily have to be the "popular" cod liver oil.