In 1996 the BBC put two large women on a motorbike and sidecar, sent them round Britain cooking with lard, cream and butter by the block, and twelve million people a week sat down to watch them refuse to apologise for it. Jennifer Paterson was sixty-eight, a Catholic who had cooked for the staff of The Spectator and been sacked for throwing the crockery out of the window. Clarissa Dickson Wright was a barrister who had drunk her way through a fortune and come out the other side. Neither had been on television. Both had been told all their lives that the way they ate was going to kill them, and both had decided they would rather be fat and fed than thin and lied to. If you watched it you remember the sound of it. Jennifer scraping an entire pack of butter into a pan while talking about the war. Clarissa holding up a lump of suet to the camera and saying the word with relish. Game pie, kidneys in cream, bacon fat poured over cabbage, a pudding made with a pound of dripping. They cooked for monks, for lifeboatmen, for the Women's Institute, in country-house kitchens with the Aga going. And every episode had a moment where one of them turned to the lens and said what nobody else on television would. Low fat was a fraud. Margarine was a chemical. Vegetarianism was for people with something wrong with them. Clarissa said if God had not meant us to eat animals he would not have made them out of meat. It went out in forty countries. The BBC had expected a curiosity and got the most watched cooking programme it had ever made. Jennifer died in 1999, of lung cancer, with a tin of caviar on the bedside table that she had asked for. Clarissa went in 2014 at sixty-six, having spent her last years defending the butcher, the gamekeeper and the dairy farmer against a country that had forgotten what they were for. They were never right about everything. They were right about the one thing the nation was being lied to about, and they said it with a sidecar and a block of butter in front of twelve million people at a time when every other cook on television was holding up a tub of spread.

There is no other material on earth that can do what a fleece does, and it grows on an animal that eats grass. It keeps a sheep alive on a Welsh hill in February, in sleet, with no shelter. It keeps a Bedouin cool in the Sahara in August. It keeps a person warm when it is soaked through, which is why mountaineers wore it to the top of Everest. It will not burn. Put a match to it and it chars and goes out, which is why it lines aircraft seats and theatre curtains. It absorbs a third of its weight in sweat and gives off heat while it does it. It blocks the sun. A wool shirt has the ultraviolet rating of a decent sunscreen. It does not smell. The surface stays too dry for the bacteria that make a shirt stink. It stretches a third of its length and springs back, so a sock holds its shape for years. It stops sound. Recording studios and classrooms line the walls with it. It stops cold in a loft as well as fibreglass does, without the itch. It soaks up oil, which is why the mats laid on spills are made of it. It dyes deeper than anything, which is why a Persian rug is still red after 300 years. It felts into a tent that a Mongolian family lives in through a minus 40 winter. And when it finally wears out, it rots into fertiliser, and the next sheep eats the grass it grew. Every one of those jobs now has a synthetic doing it worse. The sheep had all of them covered before the chemist was born, and it does it again every spring for nothing.

In 1893 a Norwegian scientist deliberately froze his ship into the Arctic ice, let it drift for three years, and lost not a single man to scurvy or anything else. Then he walked off it and spent nine months in a hole in the ground eating bear. Fridtjof Nansen was thirty-two, a zoologist with a doctorate on the nervous system of a worm. His theory was that the polar current would carry a ship across the top of the world if the ship was built not to be crushed. He built one. He called it the Fram, took twelve men, and sailed into the pack. For three years they lived in the dark and the cold with no fresh food arriving from anywhere. On every previous expedition that had meant scurvy, the disease that had killed more sailors than the sea. Nansen's crew had none. They shot polar bear and seal, and ate the meat fresh and barely cooked, as the Inuit did. The doctor on board had almost nothing to do. In 1895 Nansen and one companion left the ship on skis to make for the Pole. They got further north than any human had been, turned back, and were caught by winter on an empty island. They built a hut of stones and walrus hide, and for nine months they ate bear meat and walrus blubber and nothing else. No vegetable, no grain, no fruit. They came out in the spring fatter than they went in. Then they walked home. Nansen went on to win the Nobel Peace Prize, and lived to 68. Every schoolchild is taught that a diet without vegetables will rot you from the inside. Two men spent a winter underground on nothing but fat and meat and came out fit to walk across the Arctic, and that was 130 years ago.