What is vitamin D deficiency and how much vitamin D do you need every day?
Vitamin D deficiency occurs when your body is not sufficiently supplied with the vital fat-soluble vitamin D. Vitamin D is essential for regulating calcium and phosphate metabolism and is therefore essential for maintaining stable bones. It also plays a crucial role for the immune system and various organ functions.
The recommended daily dose of vitamin D for adults is 20 micrograms (800 international units). However, certain groups of people such as infants, young children, pregnant women, breastfeeding mothers, senior citizens and people with darker skin colour have an increased requirement. People with chronic illnesses and people who rarely spend time outdoors also usually need higher doses to cover their vitamin D requirements.
Vitamin D deficiency symptoms
The symptoms of a vitamin D deficiency can be very varied and are often not recognised immediately as they occur gradually and can be confused with other complaints. Common signs of a vitamin D deficiency are
- Muscle pain and weakness
- Bone pain and increased bone fragility (osteoporosis)
- Increased susceptibility to infections
- Depressive moods
- Headaches
- Chronic fatigue and exhaustion
- Hair loss
- Wound healing disorders
Vitamin DD deficiency symptoms in women
In addition to the general symptoms of vitamin D deficiency, women may also experience the following symptoms:
- Menstrual irregularities
- PMS (premenstrual syndrome)
- Infertility
- Pregnancy complications
Adequate vitamin D levels are particularly important for women during pregnancy and breastfeeding, as vitamin D is essential for the development of the foetus and newborn baby.
Vitamin D deficiency symptoms eyes
The eyes can also be affected by a vitamin D deficiency. Vitamin D plays an important role in eye health, particularly for the retina. A lack of vitamin D is associated with an increased risk of age-related macular degeneration (AMD) and cataracts. Studies suggest that an adequate supply of vitamin D can help to reduce the risk of these eye diseases. Dry eyes and frequent eye infections can also be signs of a vitamin D deficiency. An ophthalmological examination and determination of the vitamin D level can be useful in the event of corresponding symptoms.
Vitamin D deficiency causes
There are various reasons that can lead to a vitamin D deficiency. The most common causes are:
- Insufficient vitamin D formation in the skin due to a lack of sun exposure
- Low vitamin D intake via the diet
- Disorders of vitamin D absorption in the intestine, e.g. in chronic inflammatory diseases.e.g. in chronic inflammatory bowel diseases such as Crohn's disease or coeliac disease
- impairment of vitamin D activation in the liver or kidneys, e.g. in liver or kidney diseases
- increased vitamin D requirement, e.g. pregnancy, breastfeeding or old age
- Medications that affect vitamin D metabolism, such as anti-epileptic drugs, glucocorticoids or some antibiotics
- Obesity (severe obesity), as vitamin D is stored in fatty tissue and is then not sufficiently available to the body
- Genetic factors, that impair vitamin D utilisation in the body
Certain lifestyle factors such as high alcohol consumption or smoking can also increase the risk of vitamin D deficiency.
Vitamin D deficiency weight gain
Vitamin D deficiency may also be associated with weight gain. Studies have shown that people who are overweight or obese often have lower vitamin D levels than people of normal weight. One reason for this is that vitamin D, as a fat-soluble vitamin, is stored in fatty tissue and is therefore no longer sufficiently available to the body. On the other hand, a vitamin D deficiency can indirectly contribute to weight gain by promoting fatigue, listlessness and depressive moods, which in turn can lead to a low-mobility lifestyle and excessive eating behaviour.
Remedy vitamin D deficiency
There are various ways to compensate for a vitamin D deficiency:
- Sun exposure: Spend 10-30 minutes in the sun every day without sunscreen and with uncovered skin (face, arms, legs). However, take care to avoid sunburns.
- Vitamin D-rich diet: Consume more foods that naturally contain vitamin D or are fortified with vitamin D (see below).
- Food supplements: Vitamin D supplements can be taken in the form of tablets, capsules or drops. Have your vitamin D level determined by a blood test beforehand and discuss the dosage with your doctor.
Vitamin D drops
Vitamin D drops are a convenient and effective way to compensate for a vitamin D deficiency. They are easy to dose and are absorbed directly through the oral mucosa. Vitamin D drops are available in various dosages, mostly in the form of vitamin D3 (cholecalciferol), which is better absorbed by the body than vitamin D2 (ergocalciferol).
Vitamin D in food
There are only a few foods that naturally contain significant amounts of vitamin D. Here is an overview of the foods richest in vitamin D (animal or plant-based) with their average vitamin D content per 100 g:
Vegan sources of vitamin D
Vegan sources of vitamin D: Vitamin D content per 100 g
1. Portobello mushrooms (raw): 28.4 µg
2. Mushrooms (raw): 26.2 µg
3. Chanterelles (raw): 5.3 µg
4. Morels (raw): 5.1 µg
5. Shiitake mushrooms (dried): 3.9 µg
6. Silken tofu: 3.8 µg
7. Soya milk: 1.2 µg
8. Oyster mushrooms (raw): 0.7 µg
Animal sources of vitamin D
Animal sources of vitamin D: Vitamin D content per 100 g
1. Rainbow trout (cooked): 19 µg
2. Salmon (smoked): 17.1 µg
3. Swordfish (cooked): 16.6 µg
4. Mackerel (raw): 16.1 µg
5. Fish roe: 12.1 µg
6. Tuna (raw): 5.7 µg
7. Herring (cooked): 5.4 µg
8. Egg yolk (raw): 5.4 µg
9. Sardines (raw): 4.8 µg
10. Pork ribs (braised): 2.6 µg
However, it is difficult to cover the vitamin D requirement through nutrition alone. The German Nutrition Society (DGE) therefore recommends supporting the body's own vitamin D production through sufficient exposure to the sun.
Preventing vitamin D deficiency by drinking nutrition
Drinking meals such as those from Saturo can also contribute to the supply of vitamin D. They contain a balanced combination of nutrients, including a defined amount of vitamin D. Regular consumption of such astronaut food can help to cover the vitamin D requirement and prevent a deficiency.
Frequently asked questions
What are the symptoms of vitamin D deficiency?
Fatigue, exhaustion and poor concentration are common symptoms. Muscle pain, cramps or an increased susceptibility to infections can also be signs of a deficiency. In severe cases, it can even lead to bone softening, as vitamin D is important for the absorption of calcium.
What should you eat if you lack vitamin D?
Oily fish such as salmon, herring or mackerel are among the best sources of vitamin D. Egg yolk, mushrooms and vitamin D-fortified products such as some margarine or milk can also meet your needs. As your body produces most of the vitamin D it needs through sunlight, it is also advisable to spend time outdoors regularly.
How long does it take to correct a vitamin D deficiency?
In the case of a mild deficiency, a change in diet, dietary supplements and more sunlight can often lead to an improvement within a few weeks. If there is a more severe deficiency, high-dose vitamin D therapy is usually necessary. In this case, it takes around 2-3 months for your body to replenish its stores. Regular blood tests help to monitor the success of the therapy.
How does vitamin D deficiency affect the psyche?
Vitamin D deficiency can have a negative impact on your mental health. Studies show that low vitamin D levels are associated with an increased risk of depression and anxiety disorders. This is because vitamin D influences the production of serotonin and dopamine in the brain - two messenger substances that are largely responsible for your mood. Lack of drive, irritability and cognitive impairment can also be consequences of a deficiency.
Is it possible to consume too much vitamin D?
Yes, it is quite possible to consume too much vitamin D. An overdose is known as hypervitaminosis D and can cause health problems. Symptoms include nausea, vomiting, loss of appetite, weight loss and, in severe cases, even kidney damage. However, an overdose rarely occurs as the natural synthesis of vitamin D in the skin is stopped if there is a sufficient supply. However, high-dose food supplements can be dangerous if they are taken in an uncontrolled manner.
How much sun do you need for vitamin D?
The amount of sunlight you need to produce sufficient vitamin D depends on various factors. These include your skin type, the time of year, the time of day and where you are. In summer, 10-15 minutes of sunlight on your face, arms and legs is often enough to cover your daily requirements. People with darker skin need a little longer.
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