Most people in this country suffer from vitamin D3 deficiency. Many of them do not even know that this is the case. The problem is that vitamin D3 can only be supplied in relatively small quantities through food and the UV-B rays necessary for its formation are not available all year round in the intensity that would be required. To prevent serious deficiency symptoms, a suitable vitamin D3 preparation should be obtained in good time.
What is vitamin D3 and how is it formed in the body?
Vitamin D3 (cholecalciferol) is another name for the vitamin D produced by the human body. Its categorization as a vitamin dates back to the 1920’s: When it was discovered, it was thought to be a vitamin because it was found in various foods. However, since the fat-soluble active substance affects various tissues, the term hormone (or better: prohormone) would be more appropriate.
Humans can cover 5 to 20% of the daily requirement of vitamin D3 through consumed foods. However, in order for the biologically active D3 (calcitriol) to be formed from this, the body needs sunlight (UV-B radiation). More than 90% of it is formed in the skin cells, the rest in the kidneys and liver.
Anyone who takes advantage of the intense sunlight of the summer months to sunbathe for 15 to 30 minutes – the midday to 3 p.m. period is suitable for this – and exposes about 25% of his skin (face, arms, hands) to the blazing sun, produces much more vitamin D3 than he needs. The excess amounts are then largely stored in the body’s fat cells and released back into the blood over the winter.
Sun-seekers should take care, however, not to apply sunblock before sunbathing: It almost completely inhibits the production of the vitamin in the skin. They can apply the sunscreen afterwards. Exposing oneself to the sun in winter doesn’t do too much good, since the level of the sun in our latitudes is so low that it has little effect.
The body converts the absorbed sunlight into vitamin D3 amounts of several thousand IU (International Units) each and stores it in the fat cells. However, people with obesity have a problem with this: although the vitamin is well “deposited”, it is only insufficiently released again later, so that they may even suffer from vitamin D3 deficiency in the long term.
According to a representative study conducted by the Robert Koch Institute on behalf of the German Federal Ministry of Health on 4,000 people, 57% of male test subjects and 58% of female test subjects had too low a vitamin D level in their blood (less than 50 nmol/l or 20 ng/ml). Among those over 65 years of age, as many as 75% were affected. Pregnant women also had an undersupply of vitamin D. If women do not consume enough foods or supplements containing vitamin D3 during their pregnancy, the babies are at higher risk of developing a vitamin D deficiency disease such as rickets later on.
Other studies on vitamin D supply yielded similar results. The supply looks even worse with vegetarians and Veganern. By the complete renouncement of animal food they suffer partially from extreme Vitamin D lack.
Further groups at risk are: Children of growing age (6 to 11 years), people over 65 (their age-related thinner skin can no longer produce as much vitamin D3), people with dark skin color, bedridden people and people who hardly spend any time outdoors. In addition, vitamin D3 deficiency is sometimes linked to certain diseases.
Individuals with psoriasis have a decreased ability to synthesize vitamin D3. Patients with Crohn’s disease, kidney, liver, pancreatic and biliary dysfunction, cancer, and parathyroid disease experience impaired vitamin D absorption. People who have to take certain anti-epileptic drugs suffer from too rapid a breakdown of the vital hormone.
The German Nutrition Society (DGE) recommends a daily intake of at least 20 micrograms (800 IU), based on the sunless winter months. For infants, 10 micrograms (400 IU) daily is sufficient. Even a long-term daily intake of up to 100 micrograms is well tolerated by the body. However, long-term severe overdose can cause nausea, vomiting, severe thirst, depression, headaches, and calcium deposits in the blood vessels and organs that cause arteriosclerosis.
What is the function of vitamin D3 in the body?
The hormone is involved in many life-sustaining processes in the body. Together with calcium and vitamin K2, it ensures that sufficient calcium is always stored in the bones. Thus it effectively protects against rickets and osteomalacia (softening of the bones).
Vitamin D3 strengthens the immune system by promoting the formation of certain defense cells. In this way, respiratory diseases, colds and flu infections can be contained. In addition, thanks to its anti-inflammatory abilities, it can positively influence the severity and frequency of asthma attacks, as shown in a Japanese study of children supplemented with 1,200 IU daily.
Vitamin D3 improves the absorption of phosphates from the intestine and is capable of establishing good protection against caries. It promotes the production of antibacterial peptides that can inhibit the formation of caries-promoting bacteria and bacteria that cause gingivitis.
Recent scientific studies show that it can also curb the growth of tumor cells. Targeted administration of vitamin D3 (400 to 1,100 IU/day) has been shown to reduce mortality in cancer patients by about 15%.
Vitamin D3 also has a muscle-strengthening effect. It improves muscle performance and gives more strength, which is associated with increased mobility and a reduced risk of falls.
Heart function, circulation and blood pressure also benefit from adequate hormone intake via food or nutritional supplements. A 2012 Danish study concluded that vitamin D3 can reduce the risk of heart attack by 81%. It protects the beta cells of the pancreas, where insulin is produced, and increases insulin sensitivity so that sugar is transported more quickly from the bloodstream into the cells. Children who received vitamin D3 in infancy had about an 80% lower risk of diabetes (both types of diabetes) decades later.
The risk of developing inflammatory bowel disease, such as Crohn’s disease or ulcerative colitis, can also be reduced with a good vitamin D3 supply.
As recent studies have shown, the bacterial skin infections that frequently occur in people with neurodermatitis are due to a vitamin D3 deficiency. A supply of appropriate amounts of the hormone can therefore help to curb the disease.
The anti-inflammatory properties of vitamin D3 can protect against rheumatoid arthritis or alleviate existing symptoms, as a Canadian study shows.
Those who regularly take additional vitamin D3 at a suitable dose, at least during the winter months, can also use it to improve their brain performance well into old age. A British study of 3,000 men between the ages of 40 and 79 came to the conclusion that hormone intake can lead to improved concentration, faster thinking processes and generally better cognitive performance. Scientists have long suspected that it can even effectively inhibit degenerative processes in the brain such as Alzheimer’s and dementia.
Nerve diseases can also be prevented with it. A prolonged vitamin D3 deficiency can lead to serious nerve damage due to insufficient calcium utilization by the body.
How to recognize an undersupply of vitamin D3
If you notice one or more of the following symptoms, you should have a blood serum analysis performed as soon as possible.
Vitamin D3 deficiency symptoms often manifest themselves in the form of (increased) back and knee pain, muscle cramps, increased susceptibility to infections, skin disorders, increased tendency to fall without apparent cause, tendency to epileptic seizures, tetany, unexplained cardiac arrhythmias, tendency to depression, early signs of dementia, and constant fatigue and exhaustion.
The 25-hydroxy vitamin D3 blood analysis (for which a fee is charged) determines how high the vitamin D concentration is in the blood serum. The amounts taken in through food(s supplements) and the amount that the body could produce itself with the help of sunlight are taken into account. The precursor of the hormone calcidiol is examined, which is then later converted into the bioactive vitamin D3 (calcitriol) when required.
How to compensate for an undersupply of vitamin D3
Vitamin deficiencies can be compensated for with an increased supply of vitamin D3 or its precursor D2 via the daily diet and by taking dietary supplements. The only problem is that, apart from fatty fish, there is hardly any food that could ensure an adequate supply of the important hormone.
When it comes to fatty fish, herring in particular scores high in vitamin D3 (40.5 micrograms per 100 g of fish). So if you want to meet your minimum of 20 micrograms a day, you only need to eat at least 50 g of herring to do so. Eel and trout are in the good middle range in terms of their D3 value. 100 g salmon still has 24 micrograms/100 g.
Other animal foods cannot keep up: Eggs have only 2.9 micrograms. Milk (3.5%) is in a very bad way: 0.2 micrograms. Of the plant foods, mushrooms, with 24 micrograms/100 g, can provide a good supply of vitamin D3. Other types of mushrooms do not contain such a high concentration of vitamin D3. In the case of mushrooms, it should be taken into account that it occurs in the form of its precursor vitamin D2 (ergosterol). In addition, vitamin D3 is still added to certain types of margarine and infant milk.
Food supplements with vitamin D3
To compensate for acute and chronic deficiency of the hormone, vitamin D3 supplements are particularly suitable. Most of them contain the active vitamin D3. It is produced in the form of tablets, capsules, soft gels and drops with oil from lanolin (wool fat from sheep) or fish oil (cod liver oil). Vegetarians and vegans have the option of taking the D2 precursor (mushroom extract), lanolin D3, and more recently a preparation derived from lichen (lichen).
Sheep wool fat, although considered vegetarian, is controversial among people with this diet. If the source is not listed on the package, it is fish oil. Vitamin D3 is metabolized 1.7 times better by the body than vitamin D2. Ergosterol, which is produced in mushrooms that receive a lot of sunlight, forms ergocalciferol (vitamin D2) under the influence of UV-B radiation.
For good supplementation during the winter months, nutritional experts recommend the following dosages:
– 50 to 100 micrograms (2,000 to 4,000 IU) daily for adults with no specific excess requirement.
– 50 to 75 micrograms (2,000 to 3,000 IU) daily for children
– 10 to 12.5 micrograms (400 to 500 IU) daily for infants and young children
Patients with malabsorption (Crohn’s disease sufferers, obese patients, etc.) have a special additional need for vitamin D3.
In summer, amounts of:
– 10 to 25 micrograms (400 to 1,000 IU) daily (adults).
– 10 to 20 micrograms (400 to 800 IU) daily (children)
– 5 to 10 micrograms (200 to 400 IU) daily (infants) is quite sufficient.
In order to be able to utilize the ingested calcium optimally, it is recommended to take additional vitamin K2. A sufficient supply of magnesium (blood test!) is also necessary so that the prohormone can be converted into its bioactive forms. Existing vitamin K2 deficiency results in extremely high concentrations of calcium in the blood, which is not processed and then later deposited on the arterial walls and in the vessels of the organs.
If you want to recharge your vitamin D3 stores more quickly, choose a higher dosage in the short term, such as 50,000 IU once and then 10,000 IU daily for 4 to 6 weeks. Alternatively, 10,000 IU can be taken over a period of 8 weeks. Hypercalcemia may occur if 40,000 IU is consumed continuously or more. Babies should not receive more than 400 IU daily.
Which food supplement is best?
As a comparative study showed, vitamin D3 drops with oil are more suitable than vitamin D3 capsules, as they are better absorbed by the body. Tablets containing the hormone scored worse because they usually contain many unnecessary additives, unhealthy triglycerides and nanoparticles, the health effects of which cannot be assessed at all at present. Vitamin D3 softgels are not suitable for vegetarians/vegans because of their gelatin capsule. High-dose vitamin D3 from 20,000 IU requires a prescription. Means up to 1,000 IU are freely available.
Vitamin D3 drops
They contain vitamin D3, the antioxidant vitamin E – it prevents the oil from becoming rancid – and a healthy base oil (olive oil, hemp oil, etc.). Since the tasteless preparation is slightly oily in the mouth, some manufacturers also offer it enriched with fruit flavoring. The product usually contains no chemical additives and can be taken in drops of 200 to 5,000 IU each. The individual dosage is convenient for many users. Even higher initial doses are possible without any problems.
Vitamin D3 capsules
They contain the active ingredient in powder form and dissolve quickly in the stomach. Ideally, no colorants, lactose and filling substances are added to them. Since their shell is made of cellulose, they are also suitable for vegans and vegetarians. Vegetarians and vegans who are not comfortable with the idea that the active ingredient in the capsules is isolated from wool fat can now switch to lichen D3 or continue to swallow their vitamin D2 capsules.
In order for the hormone to be absorbed faster and better by the body, it is recommended that the capsules be consumed with a drop of cooking oil. If they are perceived as uncomfortably large in the mouth, you can also pull apart the shell and take the powder on a spoon.
Vitamin D3 and K2 combination preparations
Combination preparations that also offer the right amount of vitamin K2 are well suited for the winter vitamin store replenishment campaign. These preparations best contain vitamin D3 from lanolin or lichen and vitamin K2 from natural natto (MK-7). Again, it is important that the preparation should have as few chemical additives as possible. This is especially true if you want to take higher doses.
A minimum of 100 to 200 micrograms (4,000 to 8,000 IU) of vitamin K2 is recommended. Consumers should rather leave preparations containing MK-4 on the shelf if they value healthy and successful supplementation: MK-4 is synthesized in the laboratory and metabolized more poorly by the body than MK-7