Consumption of vitamin D through foods is possible, but there are only a few foods that really have a significant amount of vitamin D.
How much vitamin D is contained in food?
Although vitamin D is called a vitamin, it is actually a messenger substance. Vitamin D is normally produced by the body itself in sufficient quantities with the help of UVB radiation from sunlight. However, it is also absorbed through food. However, the importance of vitamin D in food is great because most people do not spend enough time outdoors to absorb the necessary amount of sunlight. Therefore, it is important to look at food, because the consequences of a deficiency for health are far-reaching.
Synthesis takes place in the body
Strictly speaking, vitamin D is first synthesized in the body. Ergocaliferol from plant food and cholefalciferol from food of animal origin serve as the basis. Synthesis takes place mainly in the kidney, but also in the liver. The need for vitamin D from food depends on the intake of vitamin D from sunlight. If this is lacking, as is the case, for example, with bedridden persons, 20 micrograms of vitamin D should be taken from food daily. Vitamin D in food is also particularly important in the following people:
- Infants for the prevention of rickets.
- In case of already existing bone softening (osteomalacia)
- Persons with chronic kidney weakness
- Persons with weakness of the parathyroid gland
- In case of existing osteoporosis
- Little exposure to the sun
- Very dark skin color
Depending on age, the need for vitamin D in food changes. Babies and seniors in old age usually have less contact with sunlight. They are therefore particularly at risk of vitamin D deficiency. Special care must therefore be taken here to ensure that the basic supply is correct.
Why is sunlight not always enough?
The need to ingest vitamin D, also through food, has increased significantly. The reason is that more and more people are protecting themselves against the sun’s rays with sunscreens. This is a fundamentally important decision that should minimize the risk of skin cancer. However, because these products block UV light, the skin is also deprived of the opportunity to absorb the necessary UVB radiation and to produce vitamin D. Vitamin D in food then ensures that the supply is nevertheless sufficient and deficiency situations do not arise in the first place.
Vitamin D during pregnancy and lactation
Pregnant women should be particularly vigilant, as a deficiency can lead to the fetus not developing properly. This obligation to take care also applies to the breastfeeding period. If a pregnant woman does not take in enough vitamin D, the vitamin D content in breast milk will drop. This leads to an undersupply of the child. Rickets can develop from this. Pregnant women and nursing mothers do not need more than the recommended amount of 20 micrograms daily for all adults. However, according to a 2008 Austrian study, women consume significantly less vitamin D. This also means that breastfeeding children may not receive an adequate supply, whereas women with a healthy diet can actually assume that exclusive breastfeeding ensures a supply of all important minerals and vitamins. So the less time women spend outdoors, the more they need to pay attention to vitamin D in foods. Overdosing is possible, but very uncommon. In 2012, the European Food Safety Authority set the tolerable upper limit at 100 micrograms.
Vitamin D table content in food:
Vitamin D content – given in µg – per 100 g foodstuff
- Salmon 16,30
- Trout 22,00
- Redfish 2,30
- Mackerel 4,00
- Tuna 4,54
- Halibut 5,00
- caviar 5,89
- Baltic herring 7,80
- Oysters 8,00
- Sardine 10,78
- Eel 20,13
- Herring 26,35
- Maties herring 28,00
- Kipper 28,75
- Sprat 32,00
- Eel 90,00
- Fats and oils
- butter 1,24
- margarine 2,50
- Cod liver oil 330,00
- Mushrooms 1,94
- Chanterelles 2,10
- morels 3,10
- Porcini mushrooms 3,10
- Egg 2,93
- curd cheese 0,09
- Chester cheese, 0,34
- Processed cheese 3,13
- Chicken liver 1,30
Vitamin D in food mainly from animal products
Lists of foods and ingredients show that vitamin D in foods cannot be taken for granted. In 2012, the German Nutrition Society also corrected its guideline values for vitamin D requirements. While until then it was still said that people needed 5 micrograms of vitamin D daily, the figures were raised significantly. Since then, there has been talk of a requirement of 20 micrograms. This does not apply to children. From the age of one, the daily intake should be 10 micrograms. Since it is not known how much vitamin D people normally absorb from sunlight, the figures may have to be adjusted again one day.
Cooking and sparing vitamin D
The healthiest ingredients are of no use if the preparation destroys valuable ingredients. This also applies to vitamin D in food. For mushrooms, which are rich in vitamin D, steaming is recommended for preparation. The prohormone D3 in foods tolerates heat, but not overcooking. Precautions that preserve vitamin D also apply to meat and fish. If possible, meat should not be washed, or only briefly, before being heated in a steamer. Leftovers can be reheated, but frequent reheating should be avoided, as the D3 is lost in the process.
Do not neglect storage of vegetables
Vitamin D in food is lost when mistakes happen during storage. Mushrooms do not spoil quickly when stored in a cool and dry place, but they lose vitamin D. However, they survive well for 2-3 days in the refrigerator. When storing, make sure that the mushrooms get oxygen.
Defrost meat and fish properly and preserve vitamin D
If possible, fish and meat should not be thawed at room temperature, otherwise vitamin D may be lost. A good way is to let vacuum-packed meat or fish defrost on a plate overnight in the refrigerator. A bowl of cold water is also suitable for gentle thawing. While it is possible to refreeze both after preparation, the vitamins will be significantly reduced. Gentle defrosting helps to preserve the vitamins.
Vitamin D in food for vegans
Vegans can suffer from vitamin D deficiency more quickly due to their abstinence than people who have more food choices. If you live vegan, you should in any case make sure to supplement your diet with the following foods to avoid serious health consequences:
- Porcini mushrooms 3.1 µg vitamin D per 100g
- Chanterelles 2,1 µg vitamin D per 100g
- Mushrooms 2.1 µg vitamin D per 100g
If you are vegan and pregnant or breastfeeding, you should inform the attending physician about your nutritional habits. In your case, regular blood testing is important to avoid undersupply and failure to thrive in the child. It may be necessary for you to ensure vitamin D levels via supplements. Complete supply via vitamin D in food is thus hardly possible.
Vitamin D in foods for vegetarians
Vegetarians have a slightly easier time than vegans getting enough vitamin D from their diet. Vitamin D in foods for vegetarian cooking is found mainly in:
- Chicken egg 2.9 µg per 100g
- Butter 1,2 µg per 100g
- Cow’s milk 0.2 µg per 100g
But, of course, mushrooms, porcini mushrooms and chanterelles also enrich the menu.vegetarians who also eat fish, should have no problem getting enough vitamin D in food.
All data on the content of vitamin D in foods are, of course, average values. The quality of these foods contributes significantly to how much vitamin D the foods actually contain. Therefore, especially in cases of vitamin D deficiency, only fresh and high-quality foods should be consumed. Long transportation routes can also contribute to a decrease in vitamin content. This also applies to foods whose ripening is delayed by cool transport and storage in darkness. But meat that is frozen several times can also lose important ingredients. If you depend on vitamin D in foods, buy local and fresh whenever possible. One thing is for sure, the importance of vitamin D in foods will continue to grow as blood tests prove that supplies are often inadequate.