FAQ

In the northern hemisphere during wintertime, the angle between the sunlight approaching the earth and its atmosphere is at a much lower level than during the summer season. Under these conditions, part of the sunlight that can pass the atmosphere during summer is reflected by the atmosphere and thus never reaches the ground. Unfortunately, this includes the UV wavelengths between 290 and 315 nm, required to produce vitamin D in our skin. As a result, our body has no option to refill its blood vitamin D level on its own between late autumn and mid-spring. Thus, most people (according to studies 80% of the population in Germany) require additional vitamin D supplementation during this period in order to prevent their blood levels from becoming deficient in vitamin D.

In the northern hemisphere during wintertime the angle between the sunlight approaching the earth and its atmosphere is at a much lower level than during the summer season. Under this conditions, part of the sunlight that can pass the atmosphere during summer is reflected by the atmosphere and thus never reaches the ground. Unfortunately this includes the UV wave lengths between 290 and 315 nm, required to produce vitamin D in our skin. As a result our body has no option to refill its blood vitamin D level on its own between late autumn and mid spring. Thus, most people (according to studies 80% of the population in Germany) require additional vitamin D supplementation during this period in order to prevent their blood levels from becoming deficient in vitamin D.

Vitamin D was initially identified in connection with the finding that cod-liver oil was found to be preventive and an effective treatment against a rickets, a childhood disease characterised by weak, soft and deformed bones. Further research revealed that UV-treatment had the same effect.

Rickets was found to develop only at Vitamin D levels below 20 ng/ml and initially low vitamin D was believed to be connected only with issues in bone formation in young children and elderly people. The idea that a Vitamin D level of 20 ng/ml may already be regarded as sufficient and does not require treatment is still widespread in part of the medical community and even some standard laboratory reporting.

In the last two decades medical studies and scientific research were able two proof that our body requires much higher blood vitamin d levels to keep all vitamin D dependant processes activated at an appropriate level . To dates common understanding of all vitamin d experts that regardless of age our body requires a vitamin d blood level of at least 40 ng/ml.

This message is spreading more and more in the last few years, due to intense activities of vitamin D experts and people, who have experienced how the adjustment of their own vitamin D level has improved their quality of life.

Sometime you will read that there is a risk of vitamin D overdosage associated o the fact that it is fat-soluble. However, this is in contrast to the finding that people with higher BMI (Body Mass Index) tend to be more likely vitamin D deficient than others. Obviously, vitamin D in the fat tissue is not directly contributing to the vitamin D blood level, because it not immediately available. Instead, the fat tissue is much more to be expected like a vitamin D sink that is a long-term vitamin D storage, only to be released in parallel to depleting the fat from the fat cells, such as in wintertime when overall nutrition is limited.

Vitamin D levels below 20 ng/ml are regarded as critical low to maintain such important body functions as bone growth and regeneration. However many gene activation processes of vitamin D require much higher levels than that. Based on numerous medical studies and scientific publications most experts recommend a level of at least 40 ng/ml as it was shown that at or above this level vitamin is showing preventative effects. A second hint, that 40 ng/ml should be the minimum level for good vitamin D supply is the fact that vitamin D is only showing up in the milk of breast-feeding women if the level is above 40 ng/ml. Vitamin D associations usually recommended achieving a vitamin D level of 40-60 ng/ml for the general public. For special purposes, e.g. to promote bone regeneration after surgery or to maximize physical power and endurance even higher vitamin D levels between 80 and 100 ng/ml seem to have optimal effects.

If your blood vitamin D level is rising, this will switch on the capability of your body to activate numerous genes, many of them producing proteins that require vitamins or minerals or other micronutrients for their activity. As a result, your requirements and consumptions of vitamins, minerals, and micronutrients, in general, will rise and you should make sure sufficient supply by either your diet or supplementation to avoid any imbalances.

Special care should be taken on a sufficient supply of Magnesium and vitamin B2, as both of them are required by the proteins activating vitamin D in your body.

Our body’s vitamin D consumption is closely connected to its general availability in the body. The more vitamin D we have in our blood, the more active we are, and thus the more vitamin D we require to be supplied to our body in order to maintain a certain activity level. Once-daily vitamin D production in the skin is decreasing rapidly (such as in autumn) and/or daily supplementation is discontinued, blood vitamin D levels usually decrease quite rapidly. The halftime of vitamin D is only about 19 days and thus even the people who were able to build a good vitamin D level during summer may face vitamin D deficiency in winter.

As always there are individual differences, both in the ability to build up vitamin D in the skin during the summer period as well as in the individual vitamin D level during the winter period. In general and without supplementation about 50% of the population in Germany is vitamin D deficient even during the summer period. The level of vitamin D deficiency is rising to 80% during the winter period.

Based on a recent VHC Vitamin D test result, the blood vitamin D level you want to achieve level r maintain, your body weight, and some additional personal parameters, your vitamin D consultant/therapist is able to estimate your individual daily vitamin D requirements. However, this first assumption might need to be adjusted due to your body’s individual ability to resort and activate vitamin D provided as a supplement. He/she might thus recommend you to come back after about 2 months in order to run a second VHC Vitamin-D test and use its result to either confirm or readjust your daily supplementation recommendation for vitamin D.

If you have checked your blood vitamin D level with e.g. the VHC Vitamin-D Test your consultant/therapist is able to adjust his recommendations for individual vitamin D supplementation without any risk, even if he/she recommends a higher daily supplementation than what is printed on the product or the package insert. In general, Even long term vitamin D supplementation of up to 10.000 I.U. vitamin D per day is regarded as save, because this is just about the amount of vitamin D your body might produce on its own provided, there is sufficient skin exposition to sunlight containing the appropriate UV wavelengths during the summer period in the northern hemisphere.

There are two different situations, in regard to this question:

a) You have been diagnosed with a low Vitamin D blood level and have started to fill up your vitamin D with supplement intake according to the advice of a vitamin D specialist:

If you alter your body’s daily uptake or production of vitamin D to a higher level than before, your blood vitamin D level is showing daily fluctuations for up too about two months until it stabilizes again. Right after the first activation step in the liver, vitamin D blood levels will rise, but then lower again, because it is absorbed by the cells of your body filling up their internal vitamin D storages for immediate requirements. Also, your fat cell will deplete part of the vitamin D in the blood and fill up your long-term vitamin D storage. It may take up to two months until this process reaches a new steady stake again. Thus you should wait for this period to reevaluate the success of your attempt to raise your blood vitamin D level to a higher level than before and to decide on whether you need to fill up more or you may continue with a supplementation sufficient to maintain the vitamin D blood level achieved,

b) Your daily vitamin D supplementation is stable and changes in overall vitamin D blood level are mainly caused by seasonal changes of vitamin D production in your skin:

You should check your blood vitamin D level at least two times per year in autumn and spring in order to decide on whether your body would benefit from additional vitamin D supplementation.