Many of us have a vitamin D deficiency. You might know that already. You may also know that vitamin D is the one vitamin we absorb through sunlight. We get no less than 80% of the amount of vitamin D we need through the sun. But what is vitamin D for, what are the consequences of a deficiency, and how can we ensure that we get enough of this "sunshine vitamin", even during the cold and dark winter months? ☀️


Vitamin D is a fat-soluble vitamin that is formed in our skin under the influence of sunlight. The vitamin is present in our nutrition to a limited extent only and can mainly be found in dairy products and fatty fish.

Vitamin D influences many processes in our body. For example, it plays a major role in the proper absorption of calcium and is therefore very important for our bone development. Vitamin D is also linked to the proper functioning of our immune system. There is even a research showing that a vitamin D deficiency can be responsible for a drop in our serotonin levels. A deficiency of serotonin can lead to sleeping problems and depression.

> Discover our vitamin D supplements


Vitamin D is undeniably essential for the proper functioning of our body and mind. An insufficient amount of vitamin D in our body can have many consequences. Find out below what the symptoms and causes of a vitamin D deficiency are.

Symptoms of a vitamin D deficiency

  • A lower resistance, which makes you sick more quickly.
  • Problems with the bones, such as osteoporosis or impaired bone development.
  • Lower psychological well-being, including irritability and feelings of depression.
  • Fatigue and sleep problems.
  • Headache.
  • Muscle pain.

Het is dus belangrijk dat we voldoende vitamine D hebben om al die negatieve gevolgen te voorkomen. Om te 
weten hoe we ons vitamine D-tekort oplossen, moeten we eerst weten waar het vandaan komt.

It is therefore important that we have a sufficient amount of vitamin D to avoid all these negative consequences. To
know how you can treat a vitamin D deficiency, you need to find out first what causes it.

Causes of a vitamin D deficiency

The cause of a vitamin D deficiency can usually is usually an insufficient exposure to sunlight. This can be for various reasons. Technological developments such as laptops and smartphones are very useful, but they also mean that we are behind our screens for longer these days. We often stay indoors or in the shade, because direct sunlight on a screen often makes it unreadable.

There is also an increasing awareness of the risks of UV radiation. It is a good thing that people are protecting themselves, but by using sun creams it is much harder for the skin to produce vitamin D under the influence of sunlight. This is also the reason why people with a darker skin tone are less likely to produce vitamin D: dark skin naturally offers a higher protection against UV radiation. Of course the seasons also play a role. Between October and March we have a lot less sun hours and the sunlight is a lot weaker.

    Although a lack of sunlight on our skin is the main cause of a vitamin D deficiency, a balanced diet is also important. When we eat enough food that is rich in vitamin D, we already reduce the shortages that occur due to a lack of sunlight. Think of dairy products such as milk and eggs or fatty fish such as salmon or mackerel. Margarine and liquid baking fat are also often enriched with vitamin D.

    Another possible cause of a vitamin D deficiency is a condition that slows down the absorption of vitamin D in the intestine. People with chronic kidney disease also have a high risk of a vitamin D deficiency.


      Although you can avoid or limit a vitamin D deficiency by getting plenty of outside air and maintaining a healthy and balanced diet, it might be a good option to use a dietary supplement. Of course, not everyone needs to take supplements all year round, but there are a number of target groups for whom a vitamin D supplement may be a necessity.

      > Discover all our vitamin D supplements

      - Pregnant and breastfeeding women: during this period you will share your vitamin D with your baby. It is very important that your baby gets a sufficient amount of vitamin D. A vitamin D deficiency can cause rickets. This is a bone formation disorder in children. We offer a selection of vitamin D supplements that also contain folic acid.

      - Growing children: a good bone development is very important in growing children. A sufficient amount of vitamin D is essential in order to prevent problems in the bone development. NutriVit D3 Liquid from Nutrisan, for example, is a vitamin D supplement that has been specially developed for children.

      - Vegetarians and vegans: people who do not eat meat, fish and even no dairy products, eat much less food that contains vitamin D. We offer vitamin D supplements that are suitable for vegetarians or vegans, for example of the brand Bioholistic.

      - Older people: since older skin produces less vitamin D and a good calcium absorption is very important to older people in order to keep the bones strong, it is certainly recommended that they maintain their vitamin D levels. We offer supplements that have been especially developed for seniors and combine vitamin D with calcium.

      - People with darker skin: due to the naturally higher protection against UV rays, vitamin D deficiency is very common in people with darker skin, especially in countries where the sun shines less often.

      - People who always cover themselves up or protect themselves against the sun: protecting your skin from UV rays is a good idea and so is taking a vitamin D supplement in this case. For example for Muslim women, it is recommended to take a supplement if their skin is not exposed to sunlight very often.

      - Everyone during the winter months: almost everyone experiences a vitamin D deficiency between the months of October and March, due to less and weaker sunlight and a higher degree of coverage of our skin. To maintain a healthy immune system and help prevent mood disorders such as winter depression, a vitamin D supplement might be helpful.


      Voedingssupplementen Vitamine D

      Pharma Nord D-Pearls 1520 Promo

        D-Pearls 1520 are soft gelatine capsules that each contain 38 µg vitamin D3. Due to their small sizes, they are easy to swallow. The fat soluble vitamin D is absorbed by the cold-pressed olive oil inside the capsules.

        • Small capsules ('pearls') with 38 µg vitamin D3 in cold-pressed olive oil.
        • The olive oil ensures a better absorbancy of the fat soluble vitamin D.
        • The gelatine is certified halal and kosher.
        • For strong bones and teeth and support of the normal muscle function.
        • Vitamin D plays a rol in absorbing calcium.
        • Supports a normal cell division.
        • Complies with the pharmaceutical directives for production and the EU-regulations for food supplements

        Natural Energy Vitamine D Complex Forte

        Natural Energy Vitamin D Complex Forte provides the body with sufficient vitamin D and thus prevents the risk of a deficiency. This supplement supports the immune system and contributes to the maintenance of a normal muscle function.

        • Contains 25 µg of vitamin D3 per capsule.
        • Keeps the calcium level  in balance.
        • Contributes to the maintenance of healthy bones and teeth.
        • Supports the cell division.
        • High bioavailability.

          Vista D3 800

          Vista D3 800 is a vitamin D supplement for adults with increased vitamin D need. This supplement contains a physiological dose of vitamin D3 (800 iu) specially adapted for adults who need a higher intake, such as pregnant women and the elderly.

          • Helps to promote a good calcium absorption.
          • Essential for the formation and maintenance of strong bones.
          • Involved in our body's defense mechanisms.
          • Helps to maintain our natural resistance.

          Nutrisan NutriVit D3 Liquid

          Nutrisan Nutrivit D3 Liquid is a dietary supplement with vitamin D3 from a natural source that provides the body with the daily need of vitamin D.

          • Supports the normal functioning of the immune system.
          • Contributes to the maintenance of a normal muscle function, healthy bones and healthy teeth.
          • Vitamin D3 comes from a natural source.
          • Vitamin D3 is dissolved in a highly absorbable and vegetarian oil.
          • No addition of preservatives, colouring and flavouring.
          • NutriVit D3 has been tested for stability: after 1 year the content of vitamin D3 was almost the same.
          • Vitamin D3 in liquid form, suitable for babies, children and adults.
          • The vitamin D3 oil is easy to dose per drop.

          ixX Pharma D-ixX 3000

            ixX Pharma D-ixX 3000 is a dietary supplement formulated with vitamin D3 and alpha linolenic acid.

            • D-ixX 3000 contains 3000 IE (international units) or 75 µg vitamin D3 per pearl & olive oil for a good absorption.
            • Suitable for the whole family, all year round.
            • Contributes to the formation and maintenance of strong bones and healthy teeth, healthy muscle function, a normal functioning of our natural resistance and a normal absorption and use of calcium and phosphorus.

            Buy your vitamin D supplement here:

            Optiphar, your online pharmacy

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