Adequate vitamin D intake does not require sunbathing for hours. A light-skinned Finn gets enough vitamin D in April to September by staying in the sun for about 15 minutes three times a week, with face and hands exposed, when the UV Index is over 3. You also get vitamin D is by eating fish and foods with added vitamin, such as dairy products.
In winter, it is necessary to take vitamin D as pills or as a dietary supplement. People with darker skins in Finland should use such vitamin supplements throughout the year.