Gulp: Adventures on the Alimentary Canal

by Mary Roach

‘Human hair, while not particularly appetizing, is Kosher’, states Rabbi Zushe Blech, the author of Kosher Food Production, on Kashrut.com ‘There is no “guck” factor’, Blech maintained, in an email. Dissolving hair in hydrochloric acid, which creates the L-cysteine, renders it unrecognisable and sterile. The rabbis’ primary concern had not to do with hygiene but with idol worship. ‘It seems that women would grow a full head of hair and then shave it off and offer it to the idol’, wrote Blech. Shrine attendants in India have been known to surreptitiously collect the hair and sell it to wigmakers, and some in kashrut circles worried they might also be selling it to L-cysteine producers.26 This proved not to be the case. ‘The hair used in the process comes exclusively from local barber shops’, Blech assures us. Phew.

The things I learn in that book... lol

He far overstated the role of gastric acid, ignoring the digestive contributions of pepsin and of pancreatic enzymes introduced in the small intestine. As is regularly evidenced by tens of thousands of gastric reflux sufferers – their acid production pharmaceutically curtailed – humans can get by with very little gastric acid. The acid’s main duty, in fact, is to kill bacteria – a fact that never occurred to Beaumont. What, for all his decades of experimenting, did he teach us? That digestion is chemical, not mechanical – but European experimenters, using animals, had shown this to be true two centuries earlier. That protein is easier to digest than vegetable matter. That gastric juices don’t require the ‘vital forces’ of the body. Not, in short, all that much. I

Random fact of the day.

Credit for the idea of using digestive enzymes for cleaning goes to chemist and Plexiglas inventor Otto Röhm.

Johnny Cash, Kurt Cobain, and Tammy Wynette had also struggled with obstinate constipation, and he was convinced that they too had stretches of paralysed colon. But these were also people who struggled with obstinate drug addictions. Opiates, whether they’re in the form of heroin or prescription painkillers, drastically slow colon motility (as do, by varying degrees, anti-depressants and other psychiatric drugs).