[devere]

Since a minor amount of summer sun exposure generates 10,000 IU of Vitamin D in the skin, Dr. Marshall and his supporters need to explain clearly how much smaller amounts of Vitamin D in the diet can have a pathological effect. The assertion seems counter-intuitive. Is there a clear theory why cholecalciferol generated in the skin by sunlight has a different physiological effect than that ingested through the digestive tract?

[ThePythonicCow]

how much smaller amounts of Vitamin D in the diet can have a pathological effect.

For the chronic illnesses that Marshall is focused on, sunlight is just as big a problem as dietary Vitamin D.

Pretty clearly, as others have noted above, what's perhaps a good treatment for some is unhealthy for most.