The bread on Britain's tables was bleached for decades with a chemical that gave dogs fits, and when the government was asked about food additives in 1951, the minister answering admitted he did not know what the word meant.
It starts with the dogs.
By the 1930s British vets had a name for something they kept seeing and could not explain. Canine hysteria. A dog would be lying by the fire, perfectly well, and then it would be up and running, yelping at nothing, crashing into furniture, fitting on the floor. Running fits, the owners called it. Vets argued about the cause for years.
The man who settled it was Sir Edward Mellanby, Secretary of the Medical Research Council, who had already spent a career feeding dogs carefully controlled diets and writing down what happened to them. He had used dogs to work out that rickets was a matter of diet a generation earlier.
In 1946 he found it. Dogs fed flour treated one particular way went into fits. Dogs fed flour without that treatment did not.
The difference was one step in the mill.
For years the milling trade had been whitening and "improving" its flour with a gas called agene. Nitrogen trichloride. Flour treated with it came out whiter, made a better-behaved dough, and could go to the baker without the weeks of natural ageing flour used to need. Quicker, whiter, cheaper. Every miller's dream.
Agene reacted with the protein in the wheat and made something new. By 1949 researchers had pinned it down: methionine sulfoximine, a compound that sends the nervous system into seizures in animal after animal. The toxin came out of the bread itself. The treatment made it from the wheat's own protein.
America banned agene in 1949.
Britain kept bleaching. On 25 May 1951 an MP stood up in the Commons and asked the Minister of Food to what extent flour was still being treated with it. In the same sitting another MP asked what control there was over chemicals added to food that might one day prove poisonous. The answer was that the Food and Drugs Act of 1938 put the responsibility on the manufacturers, and they often took the Ministry's advice.
When a member pressed him about the 700 additives in use, the man at the dispatch box said he would be very glad to look into it if his honourable friend would explain what the word additives meant. He did not know.
That was the state of oversight in the country whose chief medical research body had just shown that the nation's bread gave dogs fits.
Agene was eventually replaced. The white loaf still comes with a line on the bag that most people read past: flour treatment agent. And white flour in Britain is legally required to have things put into it: calcium since the war, iron, thiamin and niacin since the 1950s, because milling takes out what the grain had.
On 13 December, folic acid joins the list.
A food that once needed a gas to make it white, and still needs an act of Parliament to make it worth eating, sits at the base of the national plate.