Why is vitamin D important?
Vitamin D is necessary for your bones and teeth to grow and function normally. In addition, vitamin D helps the body's mucous membranes effectively fight bacteria and viruses. We have vitamin D receptors throughout the body, including in the brain, which shows how important this vitamin is to us.
How much vitamin D do we need?
The Swedish Food Agency recommends 10 micrograms per day, respectively 20 micrograms for those over 75 and those with too little sun exposure. For some groups, it may be necessary to take extra vitamin D. This mainly applies to people over 75, people who rarely spend time outdoors, pregnant women and children aged 0-2.
What happens during the winter months?
In order for us to be able to produce our own vitamin D, our skin needs to be exposed to ultraviolet light of the type UV-B. Since UV-B rays are filtered away in the atmosphere when the sun is low, it is in practice only during the summer months in Sweden (April/May to August/September between 10 am and 4 pm) that we can produce our own vitamin D in significant quantities. Approximately 15-30 minutes outdoors in the sun in the middle of the day with short sleeves and shorts is enough to fill the depots during these months in Sweden.
However, there is a limit to how much vitamin D can be stored in the body – depending on how much you have accumulated during sunny days during the summer months, it takes a different amount of time before the levels drop. For the vast majority, the levels are at their lowest in January and February. When the number of hours of sunshine decreases during the winter months, it is therefore especially important to get enough vitamin D to balance and have a normally functioning immune system. This means that the body needs to get vitamin D in a different way than through the sun during the winter months.