Raw milk started to appear more often in the news in the early twenty-first century, due to a number of books written about it and advocacy organizations which promoted the idea that raw milk is healthier for people to drink than pasteurized milk. In many areas of the United States, however, the sale of raw milk for human consumption is outlawed, and many health organizations also speak out strongly against the consumption of raw milk. With these two differing opinions, many consumers are wondering how dangerous raw milk really is. The blunt truth is that raw milk is more potentially dangerous than pasteurized milk, but when it is handled correctly, it is relatively safe, and nutritional analysis suggests that it is better for you.

When milk is not pasteurized or homogenized, it is designated as raw. Pasteurization was invented in the 1800s by Louis Pasteur, who learned that heating a food to 161 degrees Fahrenheit (71 degrees Celsius) for 15 seconds would kill most of the harmful bacteria in it. The applications for milk were realized immediately, and safe, healthy milk began to be readily accessible to many more people at reasonable prices. For people concerned about health, milk safety has always been a big issue, because it is an ideal culture medium for many bacteria, especially salmonella, brucellosis, tuberculosis, and camplyobacteriosis. By pasteurizing milk, the risk of contracting one of these illnesses is greatly reduced.

When farmers harvest raw milk for human consumption, it must be handled very carefully. First, the cows are milked in a very clean environment, and their udders are wiped down before milking to remove any sources of contamination. With a gloved hand, the farmer pulls a small amount of milk to remove bacteria that may be lurking at the tip of the teat, and to make sure that the milk is clean and healthy. Then, a milking machine is connected to the cow, and the milk is expressed directly into a chilled tank. Raw milk must be kept in a cold chain from milking to consumption, and the equipment must be spotless.

Because of the greater health risks, many raw dairies are healthier than conventional ones. The cows are fed on a diet that consists primarily of grasses, both for improved flavor and because grass-fed cows are less likely to harbor harmful bacteria in their guts. The dairy is kept cleaner and the cows are humanely treated, living longer and healthier lives. In most cases, the cows are raised with organic principles in mind, and they are not fed antibiotics or hormones. Traditional dairies, on the other hand, can afford to let their cows become infected with harmful bacteria, because pasteurization should remove it. These dairies tend to be less clean, and the individual cows are given less personal care.

Strictly speaking, raw milk is more dangerous than pasteurized milk, although raw dairies test their product extensively for bacteria and contamination, making these test results available to the public. Raw milk tends to test cleaner than conventional milk before it is homogenized, suggesting that raw milk from a conventional or less clean dairy may be more dangerous. However, raw milk is not inherently dangerous, and when purchased from a reputable source and consumed with care, it can be an excellent part of the diet: many people believe that it tastes better, contains more enzymes and minerals, and supports digestive health. People who are immunocompromised, however, should consult a doctor before consuming raw milk.