Is Raw Milk Healthy?
I've often heard that commercial cow's milk has some percentage of pus and blood allowed. Do you know if that's true? I'm assuming pasteurization removes any health risks from these contaminants. So that leads me to wonder how safe raw (unpasteurized) milk is. Is a raw-milk mocha a health risk?
Science is perplexed by the raw-milk craze. Before pasteurization became widespread, a good amount of human illness was caused by contaminated milk. Why on earth would one subject him- or herself to this danger? Answers are needed!
All milk contains pus and blood, but in a good way—pus is mostly made up of white blood cells. Milk is filled with the mother's white blood cells and antibodies, providing a child with protection from bacteria and viruses—one of the major reasons why breastfeeding a child seems to be better than bottle-feeding. (Mammal mothers lick or kiss their children to find out what bugs are infesting the child, so the proper antibodies can be added to the milk. What, you thought it was love?)
Milk typically comes out of the cow (or goat or human) without any dangerous bacteria. But think of where most milking occurs—all sorts of unsanitary things may be occurring. Milk is a particularly dangerous food precisely because it is so nutritious; a miniscule amount of contaminating bacteria can multiply in the welcoming environment, greatly increasing the chance of someone becoming ill from ingesting it. Pasteurization works by killing any of the bacteria that find their way into the milk, before they can divide and make you sick later. This little step of heating dairy before storage and transport has been one of the most effective public-health inventions of all time.
There are no health benefits in drinking raw milk—the nutrients easily survive the heating. Only breast milk for a baby is better raw, health-wise, so the white blood cells are allowed to live and do their job. (In contrast, light is horrible for milk, rapidly destroying whole classes of B vitamins.)
None of the milk-borne pathogens are fun. Salmonella causes a pretty vicious fever, nasty cramps, and an impressive amount of diarrhea. Listeria infection is everything from flu-like symptoms to meningitis. The nastiest E. coli infections result in the destruction of the kidneys and liquefaction of the brain. Thanks to a preformed toxin, powerful nausea and vomiting start within hours of consuming milk contaminated with Staphylococcus aureus. Science found himself violently ill from pasteurized milk, infested with staph at a smoothie bar, purchased at the airport a few Thanksgivings ago; it was a delightful way to greet the parents.
Despite a lesson previously learned, as your devoted empiricist, Science purchased a pint of raw goat milk and poured himself a glass. The milk was delicious—slightly salty and subtly flavorful without being gamey or overpowering. The fever, headache, and nausea came the next morning.
Sanitarily Yours, Science
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