A vitamin D deficiency has serious consequences - yet it is widespread in Germany. In winter, it is simply not possible to absorb enough sunlight and prevent a deficiency, and even in summer, a deficiency can quickly develop. This is why many people benefit from taking vitamin D oil supplements.
In our vitamin D oil test 2021 you will learn everything you need to know about the influence of vitamin D in the body, what the consequences of a deficiency are and what you need to bear in mind when taking vitamin D supplements. In addition, we show you which purchase criteria you must pay attention to in order to find the right vitamin D oil for you.
- 1 Weekly newsletter with the best personal finance tips
- 2 Summary
- 3 The Best Vitamin D Oil: Our Picks
- 4 Guide: Questions you should ask yourself before buying vitamin D oil
- 4.1 What is vitamin D oil?
- 4.2 How does vitamin D oil work?
- 4.3 When and for whom is vitamin D oil useful?
- 4.4 How can I measure the vitamin D level in my blood?
- 4.5 How can I recognise a vitamin D deficiency and what are the consequences?
- 4.6 What are the possible side effects of taking vitamin D oil?
- 4.7 What should be considered when taking vitamin D oil in children and newborns?
- 4.8 How much does vitamin D oil cost?
- 4.9 What are the alternatives to vitamin D oil?
- 5 Decision: What types of vitamin D oil are there and which is the right one for you?
- 6 Buying criteria: These are the factors you can use to compare and evaluate vitamin D oil
- 7 Facts worth knowing about vitamin D oil
- Vitamin D has an influence on almost the entire human body. A deficiency can affect the bones, nerves, immune system and cardiovascular system, among other things.
- Most Germans have a vitamin D deficiency during the winter months. But deficiencies can also occur in summer. Therefore, vitamin D oil preparations are the easiest way to prevent a deficiency or to compensate for it.
- Especially for newborns, it is very important to prevent serious damage by taking vitamin D supplements.
The Best Vitamin D Oil: Our Picks
Guide: Questions you should ask yourself before buying vitamin D oil
What is vitamin D oil?
However, many population groups now have a vitamin D deficiency, so taking a supplement is unavoidable. People who spend the entire working day indoors are particularly susceptible.(2, 3)
In addition, due to Germany's geographical location, the sun's rays are not strong enough during the winter months for the body to produce a sufficient amount of vitamin D itself.(4)
How does vitamin D oil work?
The vitamin D produced by the body is vitamin D3, while vitamin D2 is an artificial product. While vitamin D2 and vitamin D3 were still considered equivalent in some countries, vitamin D3 is now considered to be more effective.(5)
The exact areas of effect of vitamin D are still not fully researched. However, current medical research shows that vitamin D influences the entire human body and even takes on hormonal functions.(6)
However, it has been proven that vitamin D has an influence on the following areas of the human body(7):
- Cardiovascular system
- Immune system
- Mineral balance
- Calcium level
- Bone formation
When and for whom is vitamin D oil useful?
Even those who spend all day in the office or in dark rooms without contact with the sun benefit from an additional intake of vitamin D oil. (2, 3) In addition, seniors often have too low a vitamin D level and should supplement.(8)
Taking a supplement ensures an optimal vitamin D supply for the foetus. Through breastfeeding, vitamin D is passed on to the infant, so that a deficiency can be counteracted.(9, 10)
Due to the important functions of vitamin D in the human body, taking vitamin D oil is also very important for newborns and infants. The intake prevents the development of rickets, metabolic disorders and bone malformations.(11)
Taking vitamin D oil is also necessary for a variety of diseases. For example, overweight people have a higher need for vitamin D.(12) This is also the case with a whole range of diseases in the gastrointestinal tract, such as Crohn's disease, cystic fibrosis, pancreatitis or coeliac disease.(13, 14)
How can I measure the vitamin D level in my blood?
If you want to have your vitamin D level determined, you usually have to pay for the test yourself. The costs for this usually vary from practice to practice, but you should calculate about 20 euros for the test.
How can I recognise a vitamin D deficiency and what are the consequences?
The first symptoms of a mild vitamin D deficiency can be(15, 16):
- Dizzy feeling
- Constant tiredness and listlessness
- Difficulty concentrating or performing
However, these symptoms, if left untreated, can lead to more severe symptoms, which include:(17, 18)
- Higher susceptibility to infections
- Muscle weakness
- Problems in the cardiovascular system
- Favouring depression
What are the possible side effects of taking vitamin D oil?
This only happens if you take a greatly increased dose over a longer period of time. But don't worry, this cannot happen to you unintentionally, because the dangerous dose of 40,000 I.U. is about four to eight times higher than the recommended dose.(19)
Symptoms of an overdose can include the following:
- Loss of appetite
- increased thirst
- Muscle and joint pain
It only becomes serious if you maintain this overdose for several months. Since vitamin D and calcium interact, an excessive intake of vitamin D also results in an increased amount of calcium in the blood.(20)
Because of this, hypercalcaemia or hypercalcuria can occur. This leads to calcification of vessels, which in turn can promote heart attacks and kidney stones, among other things.(21)
What should be considered when taking vitamin D oil in children and newborns?
By the way, you can get a prescription from your paediatrician for the vitamin D supplement for your newborn. The health insurance will then cover all costs.
How much does vitamin D oil cost?
When buying, however, you should never be tempted by the actual purchase price alone, but always take a look at the price per 100 ml. Supposedly cheap products often simply have less content, so that in the end they are not cheaper or even much more expensive.
You can expect to pay between 20 and 95 euros per 100 ml for pure vitamin D oil. However, most preparations tend to be between about 20 and 50 pounds per 100 ml.
This sounds very expensive, but it actually means that you can get most preparations for around 10 to 25 pounds.
If you want an oil that is a mixture of vitamin D and K2, you will usually pay a little more than for a pure vitamin D oil. The price range is around 30 to 90 pounds per 100 ml, with most preparations being on the higher end of the price range.
The most expensive option is a vegan vitamin D oil. The reason for this is probably that the plant-based ingredients are more expensive than the animal-based ones. The price range for vegan preparations is around 50 to 120 pounds per 100 ml.
|Type of supplement||price per 100 ml|
|Pure vitamin D oil||approx. 20 - 95 GBP|
|Vitamin D and K2 oil||approx. 30 - 90 GBP|
|Vegan vitamin D oil||approx. 50 - 120 GBP|
What are the alternatives to vitamin D oil?
However, you should note that drops have the advantage that they are more flexible in terms of dosage. In addition, the combination of vitamin D with the oil in the drops ensures optimal absorption of the vitamin.(22, 23)
Decision: What types of vitamin D oil are there and which is the right one for you?
There are two different types of vitamin D oil, depending on the composition of the active ingredients. One is pure vitamin D oil, the other is vitamin D oil to which the active ingredient K2 is added.
In the following we would like to give you an overview of the advantages and disadvantages of both options.
What are the advantages and disadvantages of pure vitamin D oil?
Vitamin D oil has several advantages compared to the alternatives capsules and tablets. For one thing, drops are much easier to dose. You can adjust the amount you take according to your individual needs.
They are also easier to take, which is especially good for children or people who have trouble swallowing. Furthermore, drops have the least amount of additives.
The biggest advantage is the ideal effectiveness. Since vitamin D is a fat-soluble vitamin, you should always take it together with oil to ensure ideal utilisation in the body. This is already given to you by the vitamin D oil.(13)
However, in order to be able to optimally utilise calcium, your body needs not only vitamin D, but also vitamin K. If you take pure vitamin D oil, you must supplement vitamin K in another way.(24)
The disadvantages of vitamin D oil are that it has a shorter shelf life than tablets or capsules. In addition, tablets and capsules are usually much cheaper than drops.
What are the advantages and disadvantages of vitamin D oil with K2?
Vitamin D oil with added K2 has broadly the same advantages and disadvantages as pure vitamin D oil.
You can also dose vitamin D with K2 drops individually, have fewer additives and thanks to the oil, this type of vitamin D preparation is also ideally utilised by the body. Furthermore, you also have the disadvantage of a shorter shelf life and a higher price.
The only significant difference is that with this type of preparation you already have vitamin K2 mixed in and do not have to take it separately.
A disadvantage of this variant is, of course, that you cannot change the existing mixing ratio. So if your body needs more vitamin K2 than is in the mixed preparation, you still have to take another preparation to cover your needs.
Buying criteria: These are the factors you can use to compare and evaluate vitamin D oil
In the following we will show you which factors you can use to compare the different vitamin D oil preparations so that you can decide for yourself which product is right for you.
The criteria you can use to compare vitamin D oils include:
In the following paragraphs we will explain what is important in each of the criteria.
As we have already explained, with vitamin D oil preparations you always have the choice between pure vitamin D and a mixture of vitamin D and vitamin K2.
We have already listed the advantages and disadvantages of both active ingredients above. In the end, you have to decide which is the better option for you. However, if you do not want to take any additional vitamin K, we recommend that you take a preparation that already combines both active ingredients.
You can find more information about vitamin K in this video:
Vitamin D oil preparations are available in different dosages. The most common dosages are 1000, 2000 and 5000 I.U. per drop. Occasionally you can also find preparations with a lower dosage of 500 or 800 I.U., or with a higher dosage of 10,000 I.U. Products especially for babies usually have a dosage of 400 I.U.
In general, if you are not sure about the dosage, you should choose a lower dosage. If you need a higher dose, you can simply take a larger amount of drops
With a high dosage, on the other hand, it is much more difficult or impossible to reduce it.
Amount of content
Because vitamin D oil has a shorter shelf life than, for example, tablets, you should carefully consider the amount of vitamin D you want to take. You can usually get vitamin D oil drops in either 20, 30 or 50 ml vials.
If you simply buy the largest bottle, the oil may expire before you use it up. If you share the preparation with your partner or family, you can go for the larger bottle.
You should also keep a close eye on the price. Many supposedly inexpensive preparations simply have a smaller content and are even more expensive when extrapolated.
Some manufacturers label large bottles as "family packs" or tell you how many portions are in the bottle. This way you can decide whether the amount of ingredients is right for you.
You should generally avoid additives in food supplements. Especially if children or allergy sufferers take the preparations, you should keep a close eye on the additives.
Additives that you should avoid are:
- Colourings and preservatives
- Artificial flavours
- Releasing agents such as magnesium stearate
If you are vegetarian, vegan or allergic, you should pay attention to the following ingredients:
- other substances of animal origin
However, most manufacturers now state very precisely whether their product is suitable for vegetarians, vegans or allergy sufferers.
Facts worth knowing about vitamin D oil
How much, when and for how long do I take vitamin D oil?
How much and for how long you take vitamin D oil depends on your blood values. If you have a severe deficiency, your doctor will first prescribe a high-dose preparation to compensate for your deficiency.
If you do not get enough sunlight or belong to a risk group and want to prevent a deficiency, you can use the vitamin D values of the German Nutrition Society and the Federal Food Safety and Veterinary Office as a guide(25, 26):
|Age||Daily dose of vitamin D|
|Infants (up to 12 months)||400 - 1000 I.U.|
|Children (from 1 year)||800 - 2500 I.U.|
|Adolescents and adults||800 - 4000 I.U.|
|Seniors (from 65 years)||800 - 4000 I.U.|
|Pregnant and breastfeeding women||800 - 4000 I.U.|
The lower value is the minimum intake to prevent an acute deficiency, the higher value is the safe upper intake. For some time now, there has been a dispute among physicians as to whether the recommended vitamin D levels are not much too low and need to be massively corrected upwards.(27, 28)
If you are not sure what dose you should ultimately take, you can ask your doctor or use a vitamin D calculator on the internet.
What is the shelf life of vitamin D oil supplements?
Most vitamin D oil supplements have a shelf life of 6 to 12 months after opening. In general, you should follow the manufacturer's instructions, because even if a product has not gone bad after this period, the effect may be reduced. This means that you can no longer be sure that you are taking the right dose.
What is the best way to store vitamin D oil supplements?
Once you have opened a bottle of vitamin D oil, you do not necessarily have to store it in the refrigerator. However, you should not expose it to high temperatures.
Most manufacturers recommend storing the supplement in a cool place, i.e. at a temperature between 6 and 25 degrees. You should also make sure that the vitamin D oil is stored away from light and is not exposed to direct sunlight.
If you have children, you should also bear in mind that vitamin D oil is a medicinal product and should therefore be kept out of the reach of children.
In which foods does vitamin D occur naturally?
You should be aware that you can only get a small amount of your daily vitamin D from food. However, you can still consume foods that contain vitamin D for support. Foods with vitamin D include(29):
|Foods (per 100 g)||Vitamin D content in µg|
Picture source: McAdam/ 123rf.com
Der Zusammenhang zwischen Vitamin D, Mangel an Sonnenlicht, dem Ausbruch der Krankheit Rachitis und der Behandlung durch Lebertran in historischer Perspektive.
The results of this study showed that in French normal adults living in an urban environment with a lack of direct exposure to sunshine, diet failed to provide an adequate amount of vitamin D. It is important to pay attention to this rather high prevalence of vitamin D insufficiency in the general adult population and to discuss the clinical utility of winter supplementation with low doses of vitamin D.
The aim of the present study is to summarize existing literature on vitamin D levels in adults in different continents and different countries worldwide. The best determinant of vitamin D status is the serum concentration of 25-hydroxyvitamin D (25(OH)D). Most investigators agree that serum 25(OH)D should be higher than 50 nmol/l, but some recommend higher serum levels. Traditional risk groups for vitamin D deficiency include pregnant women, children, older persons, the institutionalized, and non-western immigrants. This chapter shows that serum 25(OH)D levels are not only suboptimal in specific risk groups, but also in adults in many countries. Especially, in the Middle-East and Asia, vitamin D deficiency in adults is highly prevalent.
Sunlight has long been recognized as a major provider of vitamin D for humans; radiation in the UVB (290-315 nm) portion of the solar spectrum photolyzes 7-dehydrocholesterol in the skin to previtamin D3, which, in turn, is converted by a thermal process to vitamin D3. Latitude and season affect both the quantity and quality of solar radiation reaching the earth's surface, especially in the UVB region of the spectrum, but little is known about how these influence the ability of sunlight to synthesize vitamin D3 in skin.
This meta-analysis indicates that vitamin D3 is more efficacious at raising serum 25(OH)D concentrations than is vitamin D2, and thus vitamin D3) could potentially become the preferred choice for supplementation. However, additional research is required to examine the metabolic pathways involved in oral and intramuscular administration of vitamin D and the effects across age, sex, and ethnicity, which this review was unable to verify.
This overview provides a brief description of the physiologic, endocrinologic, and molecular biologic characteristics of vitamin D. It also provides information on new selective analogs of 1alpha,25-dihydroyvitamin D3 for therapy.
It is becoming increasingly clear that vitamin D has a broad range of actions in the human body. Besides its well-known effects on calcium/phosphate homeostasis, vitamin D influences muscle function, cardiovascular homeostasis, nervous function, and the immune response. Vitamin D deficiency/insufficiency has been associated with muscle weakness and a high incidence of various chronic diseases such as cardiovascular disease, cancer, multiple sclerosis, and type 1 and 2 diabetes. Most importantly, low vitamin D status has been found to be an independent predictor of all-cause mortality. Several recent randomized controlled trials support the assumption that vitamin D can improve muscle strength, glucose homeostasis, and cardiovascular risk markers. In addition, vitamin D may reduce cancer incidence and elevated blood pressure.
Die D-A-CH-Referenzwerte für die Nährstoffzufuhr sind die Basis für die praktische Umsetzung einer vollwertigen Ernährung. Sie benennen Mengen für die tägliche Zufuhr von Energie und Nährstoffen. Die Umsetzung der Referenzwerte trägt dazu bei, Wachstum, Entwicklung und Leistungsfähigkeit sowie die Gesundheit des Menschen ein Leben lang zu fördern bzw. zu erhalten.
Routine vitamin D supplementation (400 IU/day) of breastfed infants has been recommended in North America for >50 years.1 Historically, the practice was advocated to prevent rickets; recently, there has been greater emphasis on its role in maintaining serum 25-hydroxyvitamin D concentrations (25(OH)D) above conventional thresholds of sufficiency (eg, 50 nmol/L).2 Yet, some breastfeeding advocates have argued that this policy conflicts with the message that mother's milk is a complete source of nutrient requirements in the first 6 months of life.
Compare effectiveness of maternal vitamin D3 supplementation with 6400 IU per day alone to maternal and infant supplementation with 400 IU per day.
Because there are limited natural dietary sources of vitamin D and adequate sunshine exposure for the cutaneous synthesis of vitamin D is not easily determined for a given individual and may increase the risk of skin cancer, the recommendations to ensure adequate vitamin D status have been revised to include all infants, including those who are exclusively breastfed and older children and adolescents. It is now recommended that all infants and children, including adolescents, have a minimum daily intake of 400 IU of vitamin D beginning soon after birth.
Obesity-associated vitamin D insufficiency is likely due to the decreased bioavailability of vitamin D(3) from cutaneous and dietary sources because of its deposition in body fat compartments.
These findings suggest that an oral vitamin D absorption test may be of value for determination of patients at risk for development of vitamin D deficiency. They also raise questions about the efficacy of oral vitamin D preparations in patients with intestinal fat malabsorption.
These data indicate that vitamin D malabsorption reflects the extent of distal small-bowel resection in Crohn's disease. Treatment with oral cholecalciferol is sufficient in those with small or moderate resections but oral 25-hydroxycholecalciferol supplementation may be preferred in those with a severe short-bowel syndrome.
Inadequate vitamin D status is a worldwide problem. Evidence is accumulating that individuals with low vitamin D status have excess mortality rates. We calculated to which extent annual mortality rates can be reduced in the German population by optimizing vitamin D status.
A large number of observational studies have reported harmful effects of low 25-hydroxyvitamin D (25OHD) levels on non-skeletal outcomes. We performed a systematic quantitative review on characteristics of randomized clinical trials (RCTs) included in meta-analyses (MAs) on non-skeletal effects of vitamin D supplementation.
Recent data are now available to implicate autocrine/paracrine activities in each of the major bone cell types where it also regulates cell proliferation and differentiation. In rodent models, adequate levels of serum 25-hydroxyvitamin D have been found to be critical to optimise bone health and to protect against osteoporosis.
Vitamin D receptors have been mapped throughout the brain suggesting a role for vitamin D in psychosomatic disorders. Results from previous epidemiological studies on relation between vitamin D status and depression are equivocal. Also, limited information is available relating vitamin D status with depression in young adult US population.
For adults, the 5-microg (200 IU) vitamin D recommended dietary allowance may prevent osteomalacia in the absence of sunlight, but more is needed to help prevent osteoporosis and secondary hyperparathyroidism. Other benefits of vitamin D supplementation are implicated epidemiologically: prevention of some cancers, osteoarthritis progression, multiple sclerosis, and hypertension. Total-body sun exposure easily provides the equivalent of 250 microg (10000 IU) vitamin D/d, suggesting that this is a physiologic limit.
Die Hyperkalzurie ist ein bedeutender Faktor bei der Entstehung der Urolithiasis. Hierbei handelt es sich jedoch nicht um ein einheitliches Krankheitsbild, vielmehr können ihr verschiedene Stoffwechselstörungen zugrunde liegen.
The effect of magnesium deficiency on vitamin D metabolism was assessed in 23 hypocalcemic magnesium-deficient patients by measuring the serum concentrations of 25-hydroxyvitamin D (25OHD) and 1,25-dihydroxyvitamin D [1,25-(OH)2D] before, during, and after 5-13 days of parenteral magnesium therapy.
Oil-emulsified vitamin D3 supplements resulted in a greater mean change in serum 25(OH)D concentration, but fewer patients reaching vitamin D sufficiency, than chewable or encapsulated supplements.
Vitamin D insufficiency is a common medical condition. Vitamin supplements can be ingested to improve vitamin D status. It is not known if the vehicle substance that is combined with the vitamin D tablet influences the bioavailability of vitamin D.
This paper will review the process of vascular calcification and delineate the role that vitamin K2 plays in the modulation of that process, through the activation of VKDPs. One such VKDP is Matrix Gla Protein (MGP), which when activated inhibits osteogenic factors, thereby inhibiting vascular and soft tissue calcification.
Schätzwerte für eine angemessene Vitamin-D-Zufuhr bei fehlender endogener Synthese.
Vitamin D Fachinformationen des Bundesamts für Lebensmittelsicherheit und Veterinärwesen
The IOM recommendations for vitamin D fail in a major way on logic, on science, and on effective public health guidance. Moreover, by failing to use a physiological referent, the IOM approach constitutes precisely the wrong model for development of nutritional policy.
Inappropriately low UL values, or guidance values, for vitamin D have hindered objective clinical research on vitamin D nutrition, they have hindered our understanding of its role in disease prevention, and restricted the amount of vitamin D in multivitamins and foods to doses too low to benefit public health.
Ausgewählte Fragen und Antworten zu Vitamin D
Gemeinsame FAQ des BfR, der DGE und des MRI vom 22. Oktober 2012