Vitamin D can be ingested and it can be made from skin cholesterol. Natural sunlight hitting cholesterol in our skin cell membranes turns the cholesterol into vitamin D. With reduced sunlight, in countries further away from the equator, there is reduced sunlight to turn cholesterol into vitamin D. This would logically leave more cholesterol in the body and higher cholesterol levels in areas where heart disease was found to be higher. However, the cholesterol level is in no way a cause of heart disease – it is simply a factor observed at the same time.
