Keys of Nutrition You may not be familiar with Ancel Keys, but his discoveries about nutrition and health are behind much of the dietary advice people now receive. Have you ever wondered who proved that the amount of cholesterol in food did not influence the amount of cholesterol in the blood? Do you know what causes high cholesterol? Do you like olive oil but need a good rationalization to keep using it? (hint: there is one) What dietary advice has most fascinated you, or helped you the most?