Cottonseed was a disposal problem. Gins dumped it in rivers, until Procter & Gamble hardened the oil, called it Crisco and sold it as the modern answer to lard. Whey was a disposal problem. Cheesemakers poured it down drains and fed it to pigs, until somebody dried it, put it in a tub and sold it to gym members. Skimmed milk was a disposal problem. It was what remained when the cream went for butter. It went to the pigs too, until it got a red top and a health claim. Bran was a disposal problem. Millers bagged it as animal feed, until Kellogg's boxed it in 1916 and sold it as regularity. Rapeseed oil was a disposal problem. Its market was lubricating ships' engines, and that died in 1945. Canada bred out the worst of it, renamed it canola and called it heart-healthy. Defatted soya was a disposal problem. It was what the oil mills had left over, until it was textured, flavoured and sold as a burger. Beet pulp, citrus peel and oat hulls were disposal problems. They are now listed on the pack as added fibre. Every item on that list has been sold to you as a health food. Every item on that list began as something a factory was paying to get rid of. Your great-grandmother knew exactly what to do with all of it. She fed it to the pig and ate the pig. It made the pig fat, incidentally. Nobody thought that needed a study.