Vitamin D is a hormone-like vitamin that is very important for good overall health and strong, healthy bones. Vitamin D improves the absorption, transport and utilization of calcium and phosphorus, which in turn are necessary for bone and tooth formation. It is also a factor for your muscles, heart and lungs to function optimally.
Why do we need vitamin D?
Vitamin D plays an important role in the body's cell division process and contributes to the normal function of the immune system. It simply helps cells throughout the body communicate properly. People with an appropriate level of vitamin D are usually much better equipped to fight colds and other diseases.
How do we get vitamin D?
Vitamin D is mainly found in fatty fish, wild mushrooms and egg yolks. However, it is difficult to get sufficient amounts through diet. If you are vegetarian or vegan, it is extra difficult. Vitamin D otherwise comes mainly from your skin when it is exposed to sunlight. Your body then goes through a number of chemical processes to convert it so that your body can use it in the best way. The amount of vitamin D you get from sunshine depends on:
What time of day it is – your skin produces more if you expose it during the middle of the day.
Where you live – the closer to the equator you live, the easier it is for you to produce vitamin D from sunshine year-round. In the Nordic region, we can only obtain vitamin D from the sun during summertime.
The color of your skin – light skin produces vitamin D faster than darker skin. If you have very light skin, for example, it can take about 15 minutes to produce a good amount of vitamin D, but if you have dark skin, it can take up to 2 hours.
The amount of skin you expose – the more skin you show to the sun, the more vitamin D your body produces.
Because the sun's rays are weaker and the days shorter during autumn and winter in Sweden – and we are outdoors less and have more clothes on – we in Sweden produce virtually no vitamin D at all from the sun between October and April. Therefore, a vitamin D supplement can be of great value during this period.
Low levels of vitamin D can affect energy levels, mood, depression, immune system and more. One way to find out your exact needs is to measure vitamin D in the blood either with a therapist, at a health center or privately at places like werlabs or blodkollen.
![A hand pointing at a virtual button with the text "VITAMIN D".]
Vitamin D supplements
Vitamin D exists in two forms: D2 and D3.
Both have proven to be effective in clinical studies for raising vitamin D levels in the blood, but vitamin D3 is preferable because it is utilized much better by the body and is the form that comes from natural sources: the sun and our food.
Vitamin D3 can be extracted in different ways and today there are mainly two natural sources used in supplements: sheep's wool or lichen. They are both effective and good sources of active vitamin D3, and which one you choose is entirely up to you. The one from lichen is 100% plant-based which can be an advantage for many.
A vitamin that can be good to combine with D3 is vitamin K, which is also fat-soluble and works in synergy with vitamin D to build strong bones, and is important for the blood's coagulation ability.
How much vitamin D do we need?
The best way to find out exactly how much vitamin D you need is to take a supplement for a couple of months and then take a blood test. The uptake of vitamin D supplements is individual and affected by several factors. Therefore, it is impossible to give a recommendation that applies to everyone.
The test is called 25-OH-D and can be ordered through a health center or private laboratory.
Optimal for most people is to aim for a blood value of 50-80 ng/ml or 125-200 nmol/L (there are two different ways to express measurement values for vitamin D. In Sweden, ng/ml is most common).
With that said, we recommend these doses as a starting point during the winter months in the Nordic region:
Adults:
1000-2500 IU daily (alternatively 5000 IU every other day).
Children under 12 years:
500 – 1000 IU daily.
