Farm Animal Diets

McCollum had spent the years 1912 - 1917, researching the dietary needs of farm animals. He lost his job when he began to do this research with rats. Farmers couldn't accept that dietary research on rats might apply to their cattle.

McCollum discovered Vitamin A and Vitamin D.
The daily nutriment requirements published today, are mostly based on his work.

He was called Dr Vitamin late in his career.
Worked long after retirement. Died at 89.

Elmer V McCollum

Dr Vitamin

In 1917 when Elmer V McCollum joined John Hopkins School of Public Health, the idea that the quality and variety of human food was critical to health was considered ridiculous.

If humans had enough calories to eat, what they ate was not considered important. If they were not starving they would be OK.

Farmers knew different. They knew that what they fed their animals was critical.

In this same way farmers had known for 200 years how to fatten pigs or geese. But medical doctors were reluctant to apply that understanding to their human patients.

Both medicine and nutrition as practiced at that time were not really science based, although there was some effort to discover and apply scientific principles.

Even today, we seem to be able to accept quite conflicted ideas at the same time, to keep them quite separate in our minds, not recognizing that they are incompatible.

We know for instance that the quality of the human diet is critical to health. Yet when we evaluate the diet of people on welfare, or the rations for people in refugee camps, the prime consideration is the number of calories in the diet. We choose not to know, about human nutrition, when it suits us.