Last updated: August 10, 2021

Our method

23Products analysed

34Hours spent

16Evaluated articles

100User reviews

Vitamin D is one of the 24 micronutrients that are crucial for your physical health and vitality. Normally, your body produces the vitamin itself with the help of the sun. However, a deficiency of the sun vitamin can be observed among Germans, especially in the winter months.

In our big vitamin D supplements guide 2021 we want to introduce you to the different vitamin D supplements with their advantages and disadvantages. In addition, you will find all important information on the topic of vitamin D here. This should enable you to find the right preparation for you.




Summary

  • Vitamin D is mainly known for its bone-strengthening effect. It also plays an important role in calcium and phosphate balance and in other metabolic processes in the body.
  • Most vitamin D is produced in the skin with the help of the sun and a small amount is taken in with food. If it is not possible to meet your needs in this way, we recommend taking vitamin D supplements.
  • A vitamin D deficiency can impair the normal bodily functions of humans, weaken the immune system and promote diseases.

The Best Vitamin D supplements: Our Picks

Buying criteria: These are the factors you can use to compare and evaluate vitamin D supplements

In the following we would like to show you which factors you can use to compare and evaluate vitamin D supplements. This will help you make your decision. In summary, these are the criteria:

In the following paragraphs, we present what is important in the individual criteria.

Dosage form

The dosage form is the most important distinguishing feature of vitamin D supplements. As already described in detail above, vitamin D is available in the form of tablets, capsules and drops. The different dosage forms all have advantages and disadvantages. The type of vitamin D preparation is often decisive for the price.

Dosage

The dosage is a decisive factor in buying a vitamin D supplement from many points of view. In general, you should prefer lower-dose vitamin D3 products to higher-dose supplements. This way you can better adjust the dose to your needs.

For example, if you take tablets with a dosage of 10,000 I.U. but only need 5,000 I.U., this is not healthy for your body in the long run.

On the other hand, taking a low-dose vitamin D supplement can also be very tedious. Nobody likes to swallow five tablets or capsules in a row to reach their daily dose of vitamin D. Before buying, calculate how many tablets, capsules or drops you would need to take to reach your daily dose with the product you want. At the same time, you can calculate the cost per dose. This allows you to compare vitamin D supplements in different doses, and you are sure to get the cheapest deal.

Shelf life

Each product has a best-before date (MHD). It tells you how long the effect of the preparation is guaranteed. The shelf life of vitamin D supplements varies depending on the dosage form. Vitamin D drops usually contain little to no additives and have the shortest shelf life.

You should dispose of vitamin D supplements that are over their best-before date!

We recommend that you adjust the package size to the expiry date and your required dose. After the expiry date, there may be an increased risk of side effects. If you have found a product at home that is past its best-before date, you should dispose of it properly for safety reasons.

Ingredients, additives and allergens

Depending on the form of administration, vitamin D supplements contain different ingredients, additives and allergens. Ideally, a vitamin D supplement should be free of additives and allergens such as maize, soy, yeast, peanut, gluten and lactose. For vegetarians and vegans, supplements must also not contain gelatine or other ingredients of animal origin. Additives often serve only technological purposes. They can trigger pseudoallergic reactions. Particularly sensitive persons, allergy sufferers and children should avoid these substances. Additives include:

  • Colourings and preservatives
  • Thickeners and gelling agents
  • Acidulants and flavour enhancers
  • Magnesium stearate

Understanding the composition of a vitamin D product is not always easy. Choosing the right product often takes a lot of time, especially for vegetarians, vegans and allergy sufferers. Additives are often only listed as E-numbers. If you are unsure about the ingredients, it is best to contact the manufacturer.

Guide: Questions you should ask yourself before buying a vitamin D supplement

In order to inform you comprehensively about vitamin D and to give you an understanding of the current state of science, we have summarised all the important information in the following sections.

What is vitamin D?

Vitamin D is the generic term for a group of fat-soluble vitamins called calciferols. These include vitamin D1, D2, D3, D4 and D5. Vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol) are among the most important forms. When we talk about vitamin D, we usually mean the natural vitamin D3 that is produced in the human body. All other vitamins of the D group are artificially produced.

Tageszeit für Vitamin D Einnahme

The sun's rays not only lift our spirits, they are also very important for the production of vitamin D in our bodies. (Image source: Church of the King/ Unsplash)

Vitamin D is not a vitamin in the true sense of the word, but a hormone. Unlike other vitamins, vitamin D can be produced in the body with the help of UV-B radiation. In humans, vitamin D is largely produced in the skin under the influence of sunlight and is only absorbed to a small extent through food. Vitamin D is involved in the regulation of important metabolic processes and is responsible for the regulation of entire systems of the human organism.

How does vitamin D work?

Vitamin D performs several different functions in your body. Among its most important functions is the regulation of your phosphate and calcium metabolism. However, the sun vitamin is also involved in other metabolic processes. The following paragraphs will tell you which areas of your body vitamin D can affect.

Effect on bone health

Vitamin D plays an important role in bone metabolism. The sunshine vitamin ensures that calcium and phosphate are absorbed from the intestine and incorporated into the bones. It thus plays an important role in bone mineralisation. A high vitamin D level leads less often to bone fractures(1). This was found in a study that examined people between the ages of 65 and 85. The risk of bone fracture was reduced by 22 percent in people who received vitamin D supplements.

Effect on muscles

Vitamin D also plays an important role in supplying your muscles. Muscles need vitamin D as a nutrient. A balanced vitamin D level in your body strengthens muscle performance. This is especially true for older people over the age of 60. Taking vitamin D capsules can significantly improve the functions of the lower extremities of the musculoskeletal system and relieve symptoms (2).

Vitamin D deficiency is particularly common among athletes. This leads to reduced muscle function and muscle weakness. Studies provide inconsistent results regarding the effect of vitamin D supplementation on muscle function in athletes.

Vitamin D can strengthen muscle performance and thus support athletes in particular. (Image source: unsplash / Fitsum Admasu)

Some studies see a positive influence of vitamin D supplements on muscle performance, others deny such an effect. A 2019 meta-study concluded that vitamin D supplementation positively affects muscle strength in the lower extremities, but not in the upper extremities (3).

Effect on the immune system

Vitamin D is also important for a functioning immune system. If there is a serious deficiency of the sun vitamin, the body's own defences are weakened. Vitamin D helps produce defence cells and substances and prevents inflammatory immune reactions. In addition, it seems that people with high vitamin D levels get sick less often (4).

Scientists disagree about whether vitamin D can prevent cancer. What is certain is that vitamin D influences the immune system, which is important for the defence against cancer cells (5). In a review from 2014, a research team summarised all the previously published studies on this topic - a total of 18 studies with around 50,000 people (6). The results are sobering. The researchers believe it is possible that low vitamin D levels are not the cause of certain diseases such as cancer, but merely the consequence.

Which works better - vitamin D2 or vitamin D3?

In Europe, vitamin D2 is hardly ever used as an active ingredient in vitamin D preparations. In the USA, however, vitamin D2 is still widely used. Most high-dose vitamin D preparations there contain only vitamin D2. So which form is more effective?

Your body can process both vitamin D2 and D3, but to different degrees.

While vitamin D2 has long been considered equivalent to vitamin D3, recent research suggests that vitamin D3 may be significantly more effective than vitamin D2. Vitamin D3 causes vitamin D levels to rise much faster than vitamin D2 (7).

When and for whom is a vitamin D supplement useful?

Generally speaking, as long as you eat a healthy diet, get regular outdoor exercise and do not belong to the risk groups mentioned below, you do not need vitamin D supplements. If you live in Germany, your body produces vitamin D from about March to October when you spend time outdoors.

In addition to meeting its acute needs, it also stores vitamin D reserves in fat and muscle tissue, which it can fall back on in winter. If you belong to one of the following groups of people, however, you should think about your vitamin D supply:

  • Elderly people
  • People with dark skin
  • Chronically ill people
  • Pregnant and breastfeeding women
  • Babies and small children
  • Night shift workers

Older people often only rarely come into contact with the sun or the skin's ability to produce vitamin D decreases. This can quickly lead to a vitamin D deficiency. People whose skin is more pigmented need more sunlight for their body's vitamin D production than less pigmented people.

Light-skinned people also need to be careful: If you always use sunscreen outside, UVB radiation will not reach your skin. In this way, you largely prevent the production of vitamin D.

Risk groups also include people who suffer from chronic gastrointestinal, liver or kidney diseases or who take medicines that impair vitamin D metabolism (e.g. antiepileptic or cytostatic drugs). Likewise, pregnant and breastfeeding women, infants and small children have an increased vitamin D requirement. Night shift workers or people who do not show much naked skin due to their job or for cultural or religious reasons can also benefit from an additional vitamin D intake.

What is the optimal vitamin D level?

Scientists and doctors have taken it upon themselves to determine the optimal vitamin D level. Some studies are also researching the best possible vitamin D level. Which level actually has the greatest health benefits is still a matter of debate today.
A value of 35-60 ng/ml is considered normal in Germany.

Some studies indicate that a good normal value must be at least 30 ng/ml. Moreover, a higher normal value or a value slightly above the normal range is said to have more positive effects than a value below 30 ng/ml (1, 8, 2).

The goal is therefore to maintain a level above 30 ng/ml in both children and adults in order to reap the full health benefits of vitamin D. The German Nutrition Society (DGE) speaks of a desired vitamin D supply in terms of bone health at a blood concentration of at least 20ng/ml. If the body's own vitamin D formation is lacking, this concentration is achieved with an intake of 20 micrograms of vitamin D per day.

Vitamin D supply values in ng/ml values in nmol/l
Vitamin D deficiency below 20 below 50
Vitamin D deficiency 20 to 35 50 to 80
Good to high vitamin D levels 35 to 90 80 to 225
Vitamin D over-supply 90 to 150 225 to 374
Toxic vitamin D level above 150 above 374

The concentration of 25-hydroxyvitamin D in blood serum is used as a marker for assessing supply because it reflects vitamin D intake through diet and the body's own vitamin D production. Vitamin D values can be expressed in two different units, ng/ml or nmol/l. 1 ng/ml corresponds to 2.5 nmol/l. At a normal value, there are usually no health consequences to worry about. These only become apparent in the case of an undersupply or, at the latest, a severe vitamin D deficiency below 20 ng/ml.

Vitamin D Präparate

To determine your vitamin D level, have your doctor take a blood sample. If there is a suspicion of a deficiency, the health insurance companies will pay for the test. If not, you will have to pay about 20 euros. (Image source: pixabay / Angelo Esslinger)

The only way to find out your vitamin D level is to take a blood test. If you tell your doctor about symptoms that occur with a vitamin D deficiency, he or she will carry out a blood test. However, vitamin D blood tests are usually not necessary. What you get in vitamin D in spring, summer and autumn will usually supply your body in winter as well. Vitamin D is stored in the body for several months.

What are the side effects of taking vitamin D?

If you take the right amount of vitamin D supplements, there are no side effects. However, in the case of a permanent, strong overdose or due to additives in the preparation, negative consequences can occur after taking vitamin D. However, vitamin D poisoning is very rare.

Poisoning due to excessive intake of supplements, high-dose medication or high consumption of fortified foods is possible because vitamin D, as a fat-soluble vitamin, can be stored in fat and muscle tissue.

Vitamin D is responsible for the absorption of calcium from food. If vitamin D is overdosed by food supplements over several months, this can lead to so-called hypercalcaemia, an excessive absorption of calcium. This is manifested by fatigue, exhaustion, bone pain, muscle weakness, severe thirst, nausea, vomiting, stomach pain, difficulty walking and confusion. As a result, kidney problems can also occur due to increased calcium absorption.

Vitamin D Präparate

Vitamin D poisoning is not possible through the body's own vitamin D production and natural nutrition, but it is possible through an overdose of food supplements (Image source: 29931147/ 123rf)

Your body can benefit from vitamin supplementation in many ways. However, you should not overdo it with the dosage. But there is no need to worry too much, because hypercalcaemia is only observed at a daily vitamin D dosage of about 40,000 IU. Even at very high doses of around 10,000 IU daily, however, no symptoms of hypercalcaemia could be found (9, 10).

How do I recognise a vitamin D deficiency?

A vitamin D deficiency can only be detected by a blood test at the doctor's office. If your vitamin D level is below 20 ng/ml, you can assume you have a deficiency. Often you will already notice symptoms before this. Do you often feel tired or listless, have trouble sleeping and are in a bad mood, even though your life is actually fine? These could be the first signs of a sun vitamin deficiency. The symptoms mentioned above are still mild. You can also be affected more severely, for example by:

  • Susceptibility to infections
  • poor wound healing
  • Decline in performance
  • Depression
  • Muscle and joint pain
  • Headaches
  • Hair loss
  • Cardiac arrhythmia

What vitamin D supplements are available?

There are many preparations that counteract vitamin D deficiency. They differ from each other in composition, dosage and dosage form. Basically, a distinction is made between vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). The forms occupy different stages in the utilisation process. Vitamin D3 has gained acceptance in food supplements due to its stronger effect (7). You can buy vitamin D3 in the following forms:

  • Drops
  • Tablets
  • Capsules

Each form has its advantages and disadvantages. Whether you choose vitamin D in tablets or capsules or in liquid form as drops depends solely on your preferences and needs. The following is a brief overview of the different forms of vitamin D.

Vitamin D drops

Vitamin D drops can be dosed individually and are easier to swallow than capsules or tablets. They also contain little or no additives. Therefore, drops are the ideal form of administration for babies and small children to cover their vitamin D needs.

With drops, the vitamin is already in an oily solution, which allows your body to absorb and utilise the vitamin D optimally. Studies have shown that liquid vitamin D (dissolved in oil) increases vitamin D levels more quickly than other forms of administration (12, 13).

Advantages
  • No or hardly any additives
  • Easy to take
Disadvantages
  • More cost-intensive
  • Lower shelf life

Since vitamin D drops often do not contain preservatives, they do not have as long a shelf life as capsules or tablets. When buying vitamin D, check the best-before date and choose the best package size for you. In addition to the short shelf life, the higher price is one of the disadvantages of vitamin D drops.

Vitamin D tablets

Tablets are one of the most popular forms of vitamin D. They are usually very cheap. They are usually very inexpensive and have a long shelf life. Tablets are also a very popular form of administration because of their low price.

Advantages
  • Inexpensive
  • Long shelf life
Disadvantages
  • Contain many additives
  • Harder to swallow
  • Poorer absorption of the vitamin

Additives are added to vitamin D tablets during production. Although these are considered harmless, they reduce the purity of the preparation. In addition, vitamin D tablets should be taken with meals together with some fat in order to be better absorbed by the body. In one study, the increase in vitamin D levels was lowest when taking vitamin D tablets (12).

Vitamin D capsules

Vitamin D3 soft capsules or softgels are rubbery capsules filled with vitamin D3 already dissolved in liquid. This form of preparation contains virtually no additives and is therefore purer than vitamin D tablets. In addition, the vitamin D absorption from capsules is better than from tablets (12).

Advantages
  • (Almost) no additives
  • Good absorption
Disadvantages
  • Unsuitable for vegetarians and vegans
  • More expensive

As a disadvantage, it should be mentioned that the capsule shells are often made of gelatine and are therefore not suitable for vegetarians and vegans. Capsules are also more expensive to produce than tablets. Unlike drops, however, capsules do not contain vitamin D dissolved in oil. An exception are the so-called soft capsules, which are tightly closed capsules containing vitamin D oil or gel.

How much do vitamin D supplements cost?

The prices of vitamin D supplements vary depending on the dosage form and package size. Vitamin D tablets are usually the cheapest option. However, we recommend that you consider buying the more expensive drops. They are currently considered the best choice in terms of quality and tolerability. Basically, you can get vitamin D preparations at the following prices:

Type price
Vitamin D tablets from approx. 5 euros
Vitamin D capsules from approx. 10 euros
Vitamin D drops from approx. 20 euros

As a rule, you have to pay for vitamin D supplements yourself. Only if there is an actual deficiency and your doctor prescribes the preparation will the health insurance fund cover the costs. The recommendations of the German Nutrition Society (DGE) are often used as a basis for vitamin D deficiencies, which many critics say is far too low.

What alternatives are there to vitamin D supplements?

Since humans are able to produce vitamin D themselves through sun exposure of the skin, you can alternatively make sure that you spend enough time outdoors and soak up the sun. With regular exposure to the sun, your skin can provide 80 to 90 percent of your vitamin D supply.

In order for your skin to make its own vitamin D, you need to avoid using sunscreen. Otherwise, the UVB radiation cannot be absorbed and converted.

The body's own synthesis varies from person to person and depends on latitude and season. Therefore, the DGE recommends that adults should expose themselves to the sun for about five to 25 minutes per day with uncovered face, hands and parts of arms and legs. The intensity of sunlight from March to October is sufficient for a sufficient formation of the vitamin from (11).

Your diet also contributes an estimated ten to 20 percent to your vitamin D supply. Unfortunately, only a few foods contain appreciable amounts of vitamin D. These include fatty sea fish, certain offal, edible mushrooms and eggs. These products are generally consumed in small quantities.

What is the best way to take vitamin D?

As you have already learned above, vitamin D is a fat-soluble vitamin. Therefore, you should take your vitamin D supplement together with some fat in your food, if it is not already added to your supplement. Fat allows vitamin D to develop better in the intestines. Butter or margarine, oils, cottage cheese or even yoghurt with a high fat content are particularly suitable for taking your preparation. If you are vegan, you can use vegetable oil.

What foods naturally contain vitamin D?

As mentioned earlier, your body can get a small amount of its vitamin D needs from food. Foods such as herring, salmon, mackerel, cod liver oil, eggs, milk, butter, avocados, walnuts and mushrooms are all good sources of vitamin D. Since only a few foods have vitamin D, the food portion only covers between ten and 20 percent of your vitamin D supply.

It is important to know that a sufficient intake of vitamin D is not possible through diet alone. Nevertheless, we recommend that you always include foods rich in vitamin D in your diet. The following table (according to Souci/Fachmann/Kraut, 2008) gives you an overview of foods and their vitamin D content:

Food Vitamin D (micrograms per 100 grams)
Herring 7.80 - 25.00
Salmon 16.00
Egg yolk 5.60
Mackerel 4.00
Margarine 2.50 - 7.50
Mushrooms 1.90
Butter 1.20

Should I take vitamin D in combination with other nutrients?

It is not absolutely necessary to take other nutrients in addition to vitamin D. However, if you take vitamin D3 over a period of time, you should take it in combination with other nutrients. However, if you want to supplement vitamin D3 over a longer period of time, we recommend taking vitamin D in combination with magnesium and vitamin K2 for an optimal vitamin D effect.

You should also take vitamin K because vitamin D strongly promotes calcium resorption. Vitamin K acts as a counterpart and regulates the increased calcium absorption. If your body is not sufficiently supplied with vitamin K2, excess calcium is deposited in the body and dangerous calcification of organs and vessels is possible.

Vitamin D Überdosierung-2

Vitamin D is indispensable for the body. Ideally, it produces it itself with the help of sunlight. If not, you can supplement with tablets, drops or capsules. (Image source: unsplash / pixpoetry)

You should also make sure you have a sufficient supply of magnesium. Your body needs this mineral to convert vitamin D into its active form. If there is not enough magnesium in your body, vitamin D supplementation is of no use. The vitamin remains unused because the transport molecules do not work without magnesium.

Caution: Calcium should only be supplemented by people at risk of osteoporosis to reduce the risk of bone fractures. In healthy people, an oversupply can damage the body.

Image source: Dmitrii Ivanov / 123rf

References (13)

1. Trivedi Daksha P, Doll Richard, Khaw Kay Tee. Effect of four monthly oral vitamin D3 (cholecalciferol) supplementation on fractures and mortality in men and women living in the community: randomised double blind controlled trial BMJ 2003; 326 :469
Source

2. Heike A Bischoff-Ferrari, Thomas Dietrich, E John Orav, Frank B Hu, Yuqing Zhang, Elisabeth W Karlson, Bess Dawson-Hughes, Higher 25-hydroxyvitamin D concentrations are associated with better lower-extremity function in both active and inactive persons aged ≥60 y, The American Journal of Clinical Nutrition, Volume 80, Issue 3, November 2004, Pages 752–758, https://doi.org/10.1093/ajcn/80.3.752
Source

3. Zhang, Lin & Quan, Minghui & Cao, Zhen-Bo. (2019). Effect of Vitamin D supplementation on upper and lower limb muscle strength and muscle power in athletes: A meta-analysis. PLOS ONE. 14. e0215826. 10.1371/journal.pone.0215826.
Source

4. Bjelakovic G, Gluud LL, Nikolova D, et al. Vitamin D supplementation for prevention of mortality in adults. Cochrane Database Syst Rev. 2014;(1):CD007470. Published 2014 Jan 10. doi:10.1002/14651858.CD007470.pub3
Source

5. Bouillon R (2017) Vitamin D and extraskeletal health. In Mulder JE (ed.) UpToDate. Abgerufen am 14. 2. 2017 unter www.uptodate.com/contents/vitamin-d-and-extraskeletal-health
Source

6. Bjelakovic G u.a. (2014). Vitamin D supplementation for prevention of cancer in adults. Cochrane Database Syst Rev CD007469.
Source

7. Tripkovic L, Lambert H, Hart K, Smith CP, Bucca G, Penson S, Chope G, Hyppönen E, Berry J, Vieth R, Lanham-New S. Comparison of vitamin D2 and vitamin D3 supplementation in raising serum 25-hydroxyvitamin D status: a systematic review and meta-analysis. Am J Clin Nutr. 2012 Jun;95(6):1357-64.
Source

8. Edward D. Gorham, Cedric F. Garland, Frank C. Garland, William B. Grant, Sharif B. Mohr, Martin Lipkin, Harold L. Newmark, Edward Giovannucci, Melissa Wei, Michael F. Holick, Optimal Vitamin D Status for Colorectal Cancer Prevention: A Quantitative Meta Analysis, American Journal of Preventive Medicine, Volume 32, Issue 3, 2007, Pages 210-216
Source

9. Hathcock JN, Shao A, Vieth R, Heaney R. Risk assessment for vitamin D. Am J Clin Nutr. 2007;85(1):6‐18. doi:10.1093/ajcn/85.1.6
Source

10. Vieth R. Vitamin D supplementation, 25-hydroxyvitamin D concentrations, and safety. Am J Clin Nutr. 1999;69(5):842‐856. doi:10.1093/ajcn/69.5.842
Source

11. DGE online: Wie viel Sonne braucht der Körper, um über die körpereigene Bildung ausreichend Vitamin D zu produzieren? Wie ist das im Herbst und Winter im Vergleich zum Sommer?
Source

12. Traub ML, Finnell JS, Bhandiwad A, Oberg E, Suhaila L, Bradley R. Impact of vitamin D3 dietary supplement matrix on clinical response. J Clin Endocrinol Metab. 2014;99(8):2720‐2728. doi:10.1210/jc.2013-3162
Source

13. Grossmann RE, Tangpricha V. Evaluation of vehicle substances on vitamin D bioavailability: a systematic review. Mol Nutr Food Res. 2010;54(8):1055‐1061. doi:10.1002/mnfr.200900578
Source

Wissenschaftliche Studie
Trivedi Daksha P, Doll Richard, Khaw Kay Tee. Effect of four monthly oral vitamin D3 (cholecalciferol) supplementation on fractures and mortality in men and women living in the community: randomised double blind controlled trial BMJ 2003; 326 :469
Go to source
Wissenschaftliche Studie
Heike A Bischoff-Ferrari, Thomas Dietrich, E John Orav, Frank B Hu, Yuqing Zhang, Elisabeth W Karlson, Bess Dawson-Hughes, Higher 25-hydroxyvitamin D concentrations are associated with better lower-extremity function in both active and inactive persons aged ≥60 y, The American Journal of Clinical Nutrition, Volume 80, Issue 3, November 2004, Pages 752–758, https://doi.org/10.1093/ajcn/80.3.752
Go to source
Wissenschaftliche Metastudie
Zhang, Lin & Quan, Minghui & Cao, Zhen-Bo. (2019). Effect of Vitamin D supplementation on upper and lower limb muscle strength and muscle power in athletes: A meta-analysis. PLOS ONE. 14. e0215826. 10.1371/journal.pone.0215826.
Go to source
Metastudie
Bjelakovic G, Gluud LL, Nikolova D, et al. Vitamin D supplementation for prevention of mortality in adults. Cochrane Database Syst Rev. 2014;(1):CD007470. Published 2014 Jan 10. doi:10.1002/14651858.CD007470.pub3
Go to source
Wissenschaftlicher Artikel
Bouillon R (2017) Vitamin D and extraskeletal health. In Mulder JE (ed.) UpToDate. Abgerufen am 14. 2. 2017 unter www.uptodate.com/contents/vitamin-d-and-extraskeletal-health
Go to source
Systematische Übersichtsstudie
Bjelakovic G u.a. (2014). Vitamin D supplementation for prevention of cancer in adults. Cochrane Database Syst Rev CD007469.
Go to source
Wissenschaftliche Studie
Tripkovic L, Lambert H, Hart K, Smith CP, Bucca G, Penson S, Chope G, Hyppönen E, Berry J, Vieth R, Lanham-New S. Comparison of vitamin D2 and vitamin D3 supplementation in raising serum 25-hydroxyvitamin D status: a systematic review and meta-analysis. Am J Clin Nutr. 2012 Jun;95(6):1357-64.
Go to source
Wissenschaftliche Studie
Edward D. Gorham, Cedric F. Garland, Frank C. Garland, William B. Grant, Sharif B. Mohr, Martin Lipkin, Harold L. Newmark, Edward Giovannucci, Melissa Wei, Michael F. Holick, Optimal Vitamin D Status for Colorectal Cancer Prevention: A Quantitative Meta Analysis, American Journal of Preventive Medicine, Volume 32, Issue 3, 2007, Pages 210-216
Go to source
Wissenschaftliche Studie
Hathcock JN, Shao A, Vieth R, Heaney R. Risk assessment for vitamin D. Am J Clin Nutr. 2007;85(1):6‐18. doi:10.1093/ajcn/85.1.6
Go to source
Wissenschaftliche Studie
Vieth R. Vitamin D supplementation, 25-hydroxyvitamin D concentrations, and safety. Am J Clin Nutr. 1999;69(5):842‐856. doi:10.1093/ajcn/69.5.842
Go to source
Empfehlung der DGE
DGE online: Wie viel Sonne braucht der Körper, um über die körpereigene Bildung ausreichend Vitamin D zu produzieren? Wie ist das im Herbst und Winter im Vergleich zum Sommer?
Go to source
Wissenschaftliche Studie
Traub ML, Finnell JS, Bhandiwad A, Oberg E, Suhaila L, Bradley R. Impact of vitamin D3 dietary supplement matrix on clinical response. J Clin Endocrinol Metab. 2014;99(8):2720‐2728. doi:10.1210/jc.2013-3162
Go to source
Wissenschaftliche Studie
Grossmann RE, Tangpricha V. Evaluation of vehicle substances on vitamin D bioavailability: a systematic review. Mol Nutr Food Res. 2010;54(8):1055‐1061. doi:10.1002/mnfr.200900578
Go to source
Reviews