For what it's worth, many government authorities already recommend vitamin D supplementation under varying criteria simply for general health. Because a lot of people in temperate-latitude countries really do have a mild to moderate deficiency:
> Just over two-thirds of Canadians (68%) had blood concentrations of vitamin D over 50 nmol/L -- a level that is sufficient for healthy bones for most people. About 32% of Canadians were below the cut-off. About 10% of Canadians were below the cut-off of 30 nmol/L -- a level that is considered a deficiency.
In Canada, everyone is advised to discuss it with their doctors in relation to the winter season. My doctor tests it with my routine blood work. Many people take a supplement over the winter, especially those with darker skin. And people over 50 have a blanket recommendation to take a 400 IU dose daily year-round.
> Just over two-thirds of Canadians (68%) had blood concentrations of vitamin D over 50 nmol/L -- a level that is sufficient for healthy bones for most people. About 32% of Canadians were below the cut-off. About 10% of Canadians were below the cut-off of 30 nmol/L -- a level that is considered a deficiency.
In Canada, everyone is advised to discuss it with their doctors in relation to the winter season. My doctor tests it with my routine blood work. Many people take a supplement over the winter, especially those with darker skin. And people over 50 have a blanket recommendation to take a 400 IU dose daily year-round.