Vitamin D is a fat-soluble, hormone-like substance and vitamin that the body needs for, among other things, the functions of the immune system, skeletal structure, muscle function, to increase the absorption of calcium and phosphorus, it is important for our teeth and is involved in the cell division process.
Why we need vitamin D
The short answer is that we need vitamin D because the body cannot produce the vitamin itself, it must be supplied from outside via sunlight, food or supplements. When the sun shines between September and May in Sweden, the important UVB radiation does not reach our skin even if we are exposed to sunlight, and the body cannot therefore produce vitamin D that way during this period.
This is because the sun is low and the radiation is filtered away in the atmosphere. It therefore becomes especially important to eat vitamin D, either via diet and/or food supplements to ensure the body has enough vitamin D.
Different forms of vitamin D
There are two main forms of vitamin D that are biologically active in humans: vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). Here is an overview of these two forms:
- Vitamin D2 (ergocalciferol): This form of vitamin D is found naturally in some plants and mushrooms. Vitamin D2 can also be synthesized by irradiation of yeast or fungi containing ergosterol. Vitamin D2 is a less common form of vitamin D in the diet and was used a few years ago in supplements for vegans and vegetarians. Nowadays, vitamin D3 is used in vegan vitamin D supplements as a lichen was found that can produce the active vitamin. Vitamin D2 has a similar role in the body to D3 and can be converted to the active form of vitamin D in the liver and kidneys.
- Vitamin D3 (cholecalciferol): Cholecalciferol is the form of vitamin D that forms in the skin when it is exposed to ultraviolet B (UVB) radiation from the sun. This form of vitamin D is also found in some animal foods, such as fatty fish (eg salmon, herring), eggs and meat. Vitamin D3 is the most effective form of vitamin D in raising the body's vitamin D levels, and is therefore the most common form in supplements and fortified foods.
Both forms, D2 and D3, are important for maintaining good health and supporting body functions. Vitamin D is necessary to regulate calcium absorption in the gut, strengthen bone health, support the immune system and have other positive effects on the body. Both forms can be converted to the biologically active form of vitamin D, calcitriol, in the liver and kidneys when needed, but D3 is a more efficient form.
It's important to get enough vitamin D, either through sun exposure, diet, or supplements, because a lack of vitamin D can lead to a range of health problems, including osteoporosis and reduced immune function.
3 reasons to eat vitamin D
- Vitamin D supports the immune system
- Vitamin D is needed for bone health
- Vitamin D supports muscle function
Signs of vitamin D deficiency
Many times when it comes to deficiency symptoms of vitamins or minerals, it is very diffuse and difficult to determine what is due to what. So you can't go straight to symptoms and draw a conclusion about a deficiency, but you can recognize yourself and proceed with sampling and thus find out if you suffer from a nutritional deficiency.
Common symptoms of vitamin D deficiency are reduced immune function, fatigue and a feeling of weakness in the body, muscle weakness, pain in muscles and joints, depressed mood, reduced appetite and reduced cognitive ability including memory.
Supplementation of vitamin D
A flexible alternative during autumn and winter can be to take a dietary supplement with vitamin D to ensure optimal levels during this period.
Groups at risk of deficiency are vegans and vegetarians, people who do not expose themselves to the sun during the summer, clothing and sunscreen block absorption from the sun, the elderly over 75, children (D drops are recommended from birth) and people who do not eat fat fish regularly.
There are different strengths of dietary supplements where the range is usually between 10-100 micrograms. The Swedish Food Agency recommends between 10-20 micrograms per day, every day all year round. Regardless of whether it comes from the sun, food or supplements.
It can therefore be clever to ensure the body's needs only through sun and food all year round.
Tips for counteracting vitamin D deficiency
- Expose the skin to the sun 15 min per day during the summer (without sunscreen)
- Eat fatty fish such as salmon, herring, mackerel at least 2 times a week
- Eat vitamin D-fortified foods (dairy and plant-based dairy products)
- Take vitamin D supplements
What is vitamin D good for? Common questions and answers!
What happens if you are deficient in vitamin D?
The body's immune system works worse and you are more sensitive to infections such as colds, etc. You can have muscle pain and feel weak and tired, you can become depressed and have impaired cognitive functions.
Is it good to take vitamin D?
Regardless of how you take vitamin D (via sun, food or supplements), it's good, in the right amount, of course. Vitamin D is fat-soluble and is stored in the body's fat tissue, so you should not overdose but stick to the approved range of 10-100 micrograms per day.
When not to take vitamin D?
- If you know you have high vitamin D levels, you do not need to take extra vitamin D. If you are unsure, you can either order a self-test at home and you will quickly see if you need vitamin D or not, or alternatively go to the health center and take a blood test. It is always good to test your nutritional status at regular intervals to be able to give your body what it needs.
- If you are on medication that may be affected by vitamin D, ask your doctor if you are taking medication and are unsure.
- If the food supplement contains other substances that you cannot tolerate.
Is vitamin D good for muscles?
Yes, vitamin D is good for muscle health and function. Vitamin D is important for maintaining muscle strength and function. People with vitamin D deficiency may experience muscle weakness and reduced muscle function. Older adults with low vitamin D levels have an increased risk of falling and breaking bones. Strong muscles and good muscle function are important for maintaining balance and preventing fall injuries. Vitamin D is necessary for bone health, and strong bones are linked to muscle function. A vitamin D deficiency can indirectly affect muscles by affecting bone health.
