proving that overweight men with vitamin D supplementation have experienced a significant rise in their levels. The current deficiency in vitamin D comes from the fact that we are not spending enough time in the sun, a process essential to stimulate the production of vitamin D. This exhibition should ideally take place before noon. You can also use vitamin D supplements. Advances in current research suggest that the average adult needs to take 8000 IU of vitamin D daily to raise levels above 40 ng ml, which is the minimum required for disease prevention. 7. Make sugar your enemy! levels decrease after ingestion .