Recommended Daily Allowances for nutrients were initially based on a largely carbohydrate-based diet, and the body's needs shift with carbohydrate consumption and fat intake.

“and I think again if we go back to the RDAs or the DVS whatever they call in our tea eyes they change you know over the over the decades but initially they were sort of based on a standard American diet and it was a better diet in the 40s when it was originally you know contemplated that we needed that the government needed to tell us how much to take in but it was still based on a largely carbohydrate based diet and so the the whole realm of needs shifted as a result of of I think that the stress that we were putting on our bodies by consuming carbohydrates and you know and and for a long time under consuming saturated fats and monounsaturated fats”