"You have no idea what people will do to themselves," said a veteran ER nurse...

... quoted in Mary Roach's "Gulp: Adventures on the Alimentary Canal."

“Forget to remove the potato that you used as a pessary until you noticed a vine sprouting between your legs? Decided to do your own nose job at the bathroom mirror and replace the cartilage with a leftover piece from last night’s chicken dinner? You have no idea.”

"[I]nfants whose parents sucked on their pacifiers to clean them developed fewer allergies..."

"... than children whose parents typically rinsed or boiled them. They also had lower rates of eczema, fewer signs of asthma and smaller amounts of a type of white blood cell that rises in response to allergies and other disorders."

ADDED: Saliva is underrated. From the chapter about spit in Mary Roach's "Gulp":

We are large, mobile vessels of the very substances we find most repulsive. Provided they stay within the boundaries of the self, we feel no disgust. They’re part of the whole, the thing we cherish most.

[University of Pennsylvania psychologist] Paul Rozin has given a lot of thought to what he calls the psychological microanatomy of the mouth: Where, precisely, is the boundary between self and nonself? If you stick your tongue out of your mouth while eating and then withdraw it, does the ensalivated food now disgust you? It does not. The border of the self extends the distance of the tongue’s reach. The lips too are considered an extension of the mouth’s interior, and thus are part of the self. Though culture shifts the boundaries. Among religious Brahmin Indians, writes Edward Harper, even the saliva on one’s own lips is considered “extremely defiling,” to the extent that if one “inadvertently touches his fingers to his lips, he should bathe or at the least change his clothes.”

The boundaries of the self are routinely extended to include the bodily substances of those we love. I’m going to let Rozin say this: “Saliva and vaginal secretions or semen can achieve positive value among lovers, and some parents do not find their young children’s body products disgusting.”

"If we could strip away the influences of modern Western culture and media and the high-fructose, high-salt temptations of the junk-food sellers..."

"... would we all be eating like Inuit elders, instinctively gravitating to the most healthful, nutrient-diverse foods? Perhaps. It’s hard to say. There is a famous study from the 1930s involving a group of orphanage babies who, at mealtimes, were presented with a smorgasbord of thirty-four whole, healthy foods. Nothing was processed or prepared beyond mincing or mashing. Among the more standard offerings— fresh fruits and vegetables, eggs, milk, chicken, beef— the researcher, Clara Davis, included liver, kidney, brains, sweetbreads, and bone marrow. The babies shunned liver and kidney (as well as all ten vegetables, haddock, and pineapple), but brains and sweetbreads did not turn up among the low-preference foods she listed. And the most popular item of all? Bone marrow."

Mary Roach, "Gulp: Adventures on the Alimentary Canal." (pp. 63-64).

"Think of a peanut between two molars, about to be crushed. At the precise millisecond the nut succumbs..."

"... the jaw muscles sense the yielding and reflexively let up. Without that reflex, the molars would continue to hurtle recklessly toward one another, now with no intact nut between. To keep your he-man jaw muscles from smashing your precious teeth, the only set you have, the body evolved an automated braking system faster and more sophisticated than anything on a Lexus. The jaw knows its own strength. The faster and more recklessly you close your mouth, the less force the muscles are willing to apply. Without your giving it a conscious thought."

Mary Roach writes about the science of chewing. She's a wonderfully fun writer. I've read 2 of her books — "Stiff" (about dead bodies) and "Bonk" (about sex) — and her new book is "Gulp," which I just pre-ordered for my Kindle. (As long as we're pre-ordering... "Let's Explore Diabetes with Owls.")

And here's "Gulp! The Quiz," where I learned that a certain celebrity had a "megacolon" — a colon two to three times normal size.

"The world’s most experienced penis reattachment surgeons can be found in Thailand..."

"... where, during the 1970s, an estimated one hundred vengeful Thai wives, spurred by media coverage of a prominent 1973 case, sliced off the penises of their adulterous husbands as they slept. When a suitably equipped microsurgeon was on hand to reattach the errant appendage, the men were able to resume philandering within a matter of months. Though probably with reduced success: The penises, though operative, were shorter, numb, and often only partway erectable. The most serious complication, in the Thai attacks, was infection. Two of the wives flushed the penises down the toilet, forcing their husbands to grope for their lost manhood inside the septic tank. (Incredibly, both were found, cleaned, cleaned some more, and reattached.) More commonly, the women would hurl the penis out the window. In the cases described in 'Surgical Management of an Epidemic of Penile Amputations in Siam,' all the recovered penises were 'grossly contaminated.' Better that than eaten by livestock. Many rural Thai homes are elevated on pilings, with the family’s pigs, chickens, and ducks tending to mill about seeking shade in the space underneath. It is not, oddly, the pigs, but rather the ducks, that the castrated Thai must worry about. The paper does not provide the exact number of penises eaten by ducks, but the author says there have been enough over the years to prompt the coining of a popular saying: 'I better get home or the ducks will have something to eat.'"

I'm reading "Bonk: The Curious Coupling of Science and Sex," by Mary Roach.