7 minDid you know that many Dutch people have a vitamin D deficiency all year round? This deficiency does not only occur in winter, as is often thought, but also plays a major role in summer. Because we spend less and less time outdoors and eat little oily fish, the most important natural source of vitamin D3, we simply do not get enough of it. Yet vitamin D is essential for a strong immune system and your overall health! How can you ensure you get enough vitamin D? We explain!
In this article, you will read
- Why vitamin D is so important for both your physical and mental health;
- How to get enough vitamin D;
- Whether you or another family member is at risk of vitamin D deficiency;
- The symptoms of vitamin D deficiency and long-term consequences;
- What you can do to prevent or remedy vitamin D deficiency.
What is vitamin D, and why is vitamin D important?
Vitamin D is a fat-soluble vitamin that is essential for a strong immune system and healthy bones and teeth. Vitamin D also plays an important role in your mood and is important for your heart and blood vessels.
Although vitamin D is often called ‘the sunshine vitamin’, it is actually a hormone produced by your skin. Your body produces vitamin D itself when your skin is exposed to ultraviolet B (UVB) radiation from the sun. These UVB rays convert a cholesterol-like substance in your skin into vitamin D3 (cholecalciferol). This form of vitamin D is then converted in your liver and kidneys into the active form that your body can use to support processes such as calcium absorption and bone formation.
Because vitamin D contributes to a strong skeleton, it is very important for babies and children, whose bones are still developing. Older people also benefit from sufficient vitamin D, as it supports bone density and thus reduces the risk of bone fractures and osteoporosis.
How do you get vitamin D?
In two ways: from sunlight and from food. This is quite unique, because most vitamins are obtained from food and supplemented with supplements. Only vitamins D and K are vitamins that the body can produce itself.
Vitamin D in food: vitamin D2 and D3
An important source besides sunlight is therefore our food. We obtain both vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol) from our food. What is the difference between vitamin D2 and D3?
- Vitamin D2 is found in plant-based products. D3 is also known as the animal variant, because it is obtained from animal products. The body processes vitamin D3 better than D2. Vitamin D2 is found in mushrooms, among other things.
- Vitamin D3 is mainly found in oily fish such as salmon, herring and mackerel. But it is also found in other animal products such as milk and eggs. Sometimes it is also added to cooking butter.
If you eat few foods rich in vitamin D, or if you are vegan, you can assume that you need extra vitamin D.
Sunlight
Sunlight is therefore the second source of vitamin D, specifically vitamin D3. The amount of vitamin D you produce depends on various factors such as the time of year, the time of day, your skin colour and how much skin is exposed to sunlight. In the United Kingdom, for example, the sun's strength in autumn and winter is often insufficient to produce enough vitamin D, which means that many people have to rely on food or supplements.
Vitamin D deficiency is therefore more common in winter. Many people are unaware that colds and flu are so common in winter because lower vitamin D levels affect our immune system.
But even if you don't spend enough time outdoors in the summer months when the sun is shining, you can still develop a deficiency. For example, do you work in an office? Do you eat your lunch in the canteen every day, instead of going for a walk outside? Consider how you can get enough vitamin D.
Try to go outside for 15 to 30 minutes every day, preferably between 11 a.m. and 3 p.m. You probably already knew this, but many people find it difficult to actually do it. Make sure you leave your hands and face uncovered so that your skin can absorb the sunlight and your body can produce vitamin D.
In short: you can conclude that you are deficient in vitamin D if you eat little oily fish and/or do not spend enough time outdoors. In that case, you can take additional vitamin D in the form of a supplement. You can read below how much you need.
How much vitamin D do I need?
The recommended amount of extra vitamin D from a supplement varies per age group. The Health Council of the Netherlands recommends a Recommended Daily Allowance for children and adults for all different vitamins. If there are specific groups that would benefit from taking more or less of a vitamin supplement, they provide separate supplementation advice. This also applies to vitamin D.
Extra vitamin D during pregnancy, for children and the elderly
- Children 0-4 years: 10 micrograms per day
For most vitamins, children need about 50% less than adults. That is why there are special vitamins for children that contain the correct dosage for this target group. However, children's vitamin D requirements are very high: as high as those of an adult man or woman! This is because the skin of young children is less efficient at producing vitamin D from sunlight.
It is important to start giving your baby a vitamin D supplement when they are 8 days old. Choose a natural variant, because synthetic vitamin D is not always safe for babies.
- Adults: 10 micrograms per day
Adults who eat little oily fish and do not spend 15-30 minutes in the sun every day can all use an extra 10 mg of vitamin D per day. This also applies to adults with tanned or dark skin: they cannot absorb enough vitamin D from sunlight through their skin. The RDA for vitamin D is the same for men and women.
Pregnant women are always prescribed extra vitamin D because of its relationship with calcium. Vitamin D is necessary for calcium absorption. Calcium is important during pregnancy, both for yourself as a mother and for your baby, for strong bones.
- People aged 70 and older: 20 micrograms per day
Older people actually need twice as much vitamin D as adults! This is because as we get older, we are less able to absorb vitamin D through our skin in sunlight.
Make sure you take vitamin D with a meal, because the vitamin needs to dissolve in fat for better absorption into your body.
How do you know if you have a vitamin D deficiency?
When the body has too little vitamin D, i.e. when vitamin D levels are low, we refer to this as vitamin D deficiency. The Health Council of the Netherlands states that vitamin D levels below 30 nmol per litre can be harmful to the skeleton. Vitamin D plays a role in maintaining strong bones, teeth and supple muscles. A vitamin D level of 80 nmol per litre is optimal.
A vitamin D deficiency can occur because you are not getting enough vitamin D, but there are also people whose bodies do not absorb the vitamin properly. You can have your vitamin D level checked by your doctor with a blood test.
Vitamin D deficiency symptoms
Do you feel low on energy or even lethargic, do you suffer from cramps or muscle tremors and muscle pain? These can be signs of a vitamin D deficiency.
A deficiency can often be recognised by a number of physical symptoms. Vitamin D ensures strong bones and teeth and proper muscle function in the body. If you have a deficiency of this vitamin, you may notice it in these parts of the body.
You can recognise a vitamin D deficiency by the following symptoms:
- Low energy
- Reduced immunity
- Lethargy
- Muscle or joint pain
- Weak muscles
- Cramps and muscle tremors
- Bleeding or painful gums
What are the consequences of a vitamin D deficiency?
Of course, the above symptoms of vitamin D deficiency do not all occur immediately. In other words, with a slight vitamin D deficiency, the symptoms are less severe than with a chronic deficiency. Symptoms worsen over time if you do not replenish your vitamin D deficiency:
- Vitamin D is necessary for the intestines to absorb calcium from food. Vitamin D and calcium therefore need each other. If you have a vitamin D deficiency, you will also develop a calcium deficiency. A calcium deficiency causes new problems, such as fatigue, tingling in your fingers and/or toes, but also an increased risk of bone decalcification in later life. The official name for bone decalcification is osteoporosis. Osteoporosis cannot be cured.
- Vegans in particular are at risk of not getting enough calcium because they do not eat dairy products. A vitamin D deficiency further increases this risk. In addition to a vitamin D supplement, it is therefore advisable for this group to take a calcium supplement as well.
- Vitamin D is one of the most important vitamins for your immune system. It may even be the most important, because even a slight vitamin D deficiency can make you more susceptible to colds and flu. Your immune system is the result of your body's defence mechanism, which keeps bacteria and viruses at bay.
- In addition to physical symptoms, vitamin D is also known to cause mental health issues. Anxiety and hyperventilation occur in people who are deficient in vitamin D, as well as low mood and depression.
Pay close attention to the symptoms of vitamin D deficiency in your children. In the long term, a vitamin D deficiency can lead to rickets, a bone disorder that can cause deformities and small fractures in the bones.
Risk groups for vitamin D deficiency
Who is most at risk of vitamin D deficiency? These are people who cannot absorb enough vitamin D from sunlight through their skin. These include smallchildren (0-4 years), senior citizens (70 years and older), vegans, people with dark or tanned skin, and people who wear clothing that covers their skin.
There are also a few groups who may benefit from taking a vitamin D supplement for other reasons. These are pregnant women and women going through the menopause. Even if you eat oily fish during pregnancy and get enough sunlight, you still need 10 mg of extra vitamin D from a supplement. This is because your unborn baby is completely dependent on you for its vitamin D supply. If you have a vitamin D deficiency, your baby will also have this at birth.
After the menopause, the female body produces less oestrogen. This can cause mood swings or feelings of depression. Vitamin D plays an important role in our mood, which means that women going through the menopause can benefit from extra vitamin D. The requirement is no higher than for other adult women (aged 19-69), but vitamin D can be particularly beneficial for them in relation to mood complaints.
Conclusion
Vitamin D is extremely important for your health, whether you are young or old. It keeps your bones strong, maintains your immune system and improves your mental well-being. Because many people do not get enough vitamin D, for example due to insufficient sunlight or not eating enough oily fish, it is wise to be mindful of this. Children, the elderly, pregnant women and people who do not spend much time outdoors should be particularly careful. By getting some sun every day, eating healthily and possibly taking a supplement, you can ensure that you get enough vitamin D. This will keep you fit, energetic and simply feeling better about yourself!
