Vitamin D is essential for human life. It plays a central role in calcium and phosphate metabolism and is important for the immune system, cell growth and the fight against cancer, among other things. Vitamin D receptors have been found in over 30 target tissues. Vitamin D is a fat-soluble compound that is essential for a healthy mineral balance. The precursor of vitamin D is called cholecalciferol or vitamin D3. This substance is converted into the active vitamin D (calcitriol) in the body.
Functions of vitamin D
Vitamin D acts like a hormone in the body. It is important for the health of teeth, bones and muscles. Vitamin D also regulates the calcium and phosphate balance, controls the storage of calcium in the bones and protects against demineralization of the bones, so-called osteoporosis, after menopause. It is important for cell growth and inhibits tumor differentiation in some types of cancer. In addition, it also supports the immune system. In old age, a deficiency promotes falls and fractures. In children, vitamin D develops a strong and well-formed skeleton and healthy teeth. In recent years there has also been increasing evidence that vitamin D could have a beneficial effect on the course of chronic and serious diseases.
Sources of vitamin D
Our body can produce vitamin D itself. When we are in the sun, vitamin D3 is formed in our skin, which is then converted to vitamin D. On a sunny summer day, the daily requirement is covered many times over - at least in theory. Because the light intensity and thus the formation of vitamin D3 in the skin are influenced by many factors such as the position of the sun, the height above sea level, the weather, etc. Window glass absorbs almost all the necessary UV-B components in sunlight. Sunscreen impedes vitamin D3 production by more than 97% from a sun protection factor of 8. Everything that gets between the bright sky and the skin reduces or makes it impossible for the skin to produce vitamin D. Due to our modern lifestyle, many people are not in the sun enough or use sun protection cream too quickly in order to be able to produce enough vitamin D.
In winter, the situation becomes even more precarious. In order for sunlight to contain sufficient UV-B rays for vitamin D synthesis, the sun's rays must hit the earth at an angle of more than 35°. In Switzerland, this is only the case from March to mid-October. In the winter months, any vitamin D reserves in the body and food are the only natural sources. About 20 percent of daily needs can be covered via the latter. Vitamin D is found in some high-fat foods, such as oily fish, offal, eggs and, to a limited extent, in dairy products.
Widespread deficiency
Only in recent years has it been increasingly recognized which diseases of civilization are associated with the widespread lack of light in modern societies. It can be assumed that at least 70% of the Swiss population has a vitamin D deficiency. The following risk groups are particularly at risk:
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People who rarely spend time in the sun.
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People who are overweight (possibly due to increased absorption of vitamin D in adipose tissue)
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Older people (skin produces less vitamin D)
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Pregnant and lactating women (increased need)
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newborn
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People with dark skin type (needs more UV exposure)
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Taking medication (e.g. cortisone)
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Patients with malabsorption, chronic renal failure or chronic liver disease
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People who are veiled for cultural/religious reasons.
Official recommendations are too low
Today's recommendations for daily allowances are considered by many professionals to be either irrelevant (for individuals sufficiently exposed to UVB light) or insufficient (for the majority of the population in civilized societies at higher latitudes). After all, the official recommendations have been raised in recent years and are now 800 IU (International Units) or 20 micrograms per day for adults. However, my experience is that a dosage close to the maximum daily dose of 4000 IU or 100 micrograms is more effective in many cases. In winter, 5000 IU per day can be taken without hesitation, while in summer it can be reduced to 3000 IU. A vitamin D overdose is not to be feared at doses of up to 10,000 IU per day. To maintain the level of vitamin D in the blood, 2000 IU daily are necessary (study Holick MF et al., J.Clin. Endocrin. Metabol., Published ahead of Print, June 6, 2011).
Vitamin D can have a preventive or curative effect in the following indications:
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allergies
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eczema
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autoimmune diseases
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intestinal diseases
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inflammation of the joints
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neurological diseases
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Frequent infections
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osteoporosis
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Cancer
Vitamin D in osteoporosis
Osteoporosis is a common disease of bones in old age, making them more susceptible to fractures. It is excellently treated (or avoided) by taking vitamin D (3000-4000 IU) and vitamin K2 (200 micrograms). These two vitamins complement each other and synergistically promote bone remineralization. A sufficient supply of magnesium must also be ensured.
If there is a lack of vitamin D, the bone-building cells (osteoblasts) decrease and the bone volume dwindles. This can be corrected by taking vitamin D. Vitamin D also promotes the maturation of the bone-degrading cells (osteoclasts) via a further control circuit and thus indirectly promotes bone degradation. This effect of vitamin D is suppressed by the simultaneous intake of vitamin K2.
At the same time, vitamin K2 is essential for the body's own production of osteocalcin, a protein that is involved in bone mineralization. Vitamin K2 is best taken in the more sustained and effective MK7 form. When taking magnesium, it is important to pay attention to which salt it is bound to. Magnesium citrate has an unfavorable effect on the supply of iron.
If necessary, the hormones must also be looked at. On the other hand, supplementation with calcium is unnecessary, since we take in more than enough calcium with food. It is also not necessary to eat extra dairy products.
With high doses of vitamin D, also add vitamin K2
As already mentioned, vitamin D and vitamin K2 have a synergistic effect, i.e. they belong together and complement each other. For this reason, if you take more than 8000 IU of vitamin D daily, I recommend taking 200 µg of vitamin K2 at the same time. Vitamin K2 directs excess calcium from the blood into the bones. It ensures that the calcium is not deposited on the walls of blood vessels (arteriosclerosis) or in the form of kidney stones, but is supplied to the bones. At the same time, vitamin K2 can prevent the dreaded arteriosclerosis, but also prevent or treat osteoporosis. Vitamin D therefore promotes the absorption of calcium, which explains why the interaction of vitamin K2 is all the more important when taking higher amounts of vitamin D.
Vitamin D in old age
Because the skin's own production of vitamin D decreases with age and many older people avoid direct sun exposure, vitamin D deficiency is particularly common among older adults (more than 50% in general, more than 80% in hip fracture patients). Vitamin D not only strengthens bones, but also improves coordination, balance and muscles. Therefore, with an adequate vitamin D supply, not only are the consequences of falls less severe (because the bones are stronger), but there are also significantly fewer falls overall (Basler fall study, Bischoff HA et al, J Bone Miner Res 2003; 18 ; 343-351). Vitamin D as an effective measure to prevent falls and broken bones thus corresponds to a central public health concern.
Vitamin D for newborns, babies and toddlers
Babies and small children are growing rapidly and are now increasingly being protected from the sun's rays. Exactly these rays of the sun would be necessary for the formation of vitamin D. According to the literature, breast milk intake is not sufficient to feed infants. Food also makes only a small contribution. Therefore, the vitamin should be supplemented.
Vitamin D supplementation in the form of drops is recommended for infants from 3 months and children up to their 3rd birthday, 400 IU in the 1st year of life, 600 IU in the 2nd and 3rd year of life.
The drops with vitamin D can be administered directly into the mouth, on the pacifier or with a spoon. It can also be mixed with breast milk, milk or porridge. However, it is important to ensure that it is consumed in its entirety.
Pregnant and breastfeeding women should also ensure that they take a sufficiently high vitamin D supplement at all times of the year.
Vitamin D and Cancer
If the blood level of vitamin D (25-OH-vitamin D3) is constantly at least 100 nmol/l, or even better 150-200 nmol/l, the risk of getting cancer is reduced by 60%! Vitamin D inhibits the growth of cancer cells in several places, so it can be used both to prevent and treat cancer. Such treatment always belongs in the hands of a professional, the right dose under control is crucial. It has been found to work best on breast, colon and pancreas cancers, while being less effective on prostate cancer.
Production of vitamin D
Vitamin D is obtained industrially from wool fat. When washing sheep's wool, wool fat (lanolin) accumulates. This is purified in several steps (at least 200°C, 20 minutes, by transesterification or hydrolysis). Cholesterol is then extracted from this, which is converted into cholecalciferol (vitamin D3) by means of UV radiation and pressure. The vitamin D3 is then purified. Although this is very unlikely, the end product may contain traces of wool fat and is therefore vegetarian but not vegan. Vegan vitamin D is almost non-existent.