Good post. The only real source for Vit D its the sun, what we take from supplements cant be asimilate by the organism very well like most of the vitamins and minerals.
Supliments are synthetic and the rate of asimilation its very low, under 20%.
Morning rays helps organism to recover alot, its a natural healer.
Many scientific theories/observations encourage people to stay more under the sunlight.
Even the food doesnt have big amount of vitamins because people put synthetic substance to help me grow.
Valid points you've raised. Coupled with the fact that Vitamin D2 has low affinity for Vitamin D binding proteins, vitamin D3, which comes mainly from the sun is the best source of vitamin D anyone can get.