In 1928 a Chicago paediatrician let babies choose their own dinner from 34 foods, and for six years not one of them chose the way the pamphlet says.
Clara Davis took fifteen infants just weaned, and put a tray in front of them at every meal.
Beef, lamb, chicken, liver, kidney, brains, bone marrow, fish, eggs, milk, bananas, oats, carrots, peas, cabbage, salt. Nothing processed. No sugar.
Nobody steered. The nurse held the spoon, the baby pointed.
One boy ate seven eggs a day for a stretch. Another lived on bananas for a fortnight and then would not look at one.
They chewed bone marrow. They drank the beef juice. They pushed the greens round the tray.
One baby arrived with rickets. She put cod liver oil on the tray and left it there. He drank it, unprompted, until the rickets healed, and then never touched it again.
Six years. Not one case of stomach trouble. Not one deficiency. Visitors said they had never seen healthier children.
The doctors who examined them wrote it up as the wisdom of the body.
Nobody had taught these children that the yolk was bad or the marrow was rich or the cabbage was the healthy part.
Left alone with the food, a one-year-old built itself a diet heavy in the animal and ate the plants as a side when the mood took it.
The experiment is almost a century old. The pamphlet is still telling his mother to start with the carrot.