exposes the milk to an elevated temperature for a period of time sufficient to destroy certain microorganisms, those that can produce disease or cause spoilage, without radically altering taste or quality.
According to the FDA (Food and Drug Admin) pasteurization kills off the possibility of exposing the drinkers of the processed milk to Tuberculosis, diphtheria, polio, salmonellosis, strep throat, scarlet fever and typhoid fever. It also gives milk a longer stable shelf life of 2-3 weeks. Also with processing the milk you remove the possibility of animal bacteria to enter the milk from unclean utters, or barn areas.
Cons for Pasteurization
Depletion of certain vitamins such as thiamin(b-1), pyridoxine(b-6), cobalamin(b-12), folic acid and vitamin C. Thiamin if you don't know helps the body convert carbs into energy and it is also considered the anti stress vitamin because it enhances the activity of the immune system and improves the body's ability to handle stressful circumstances. Pyridoxine also converts carbs into energy and it also converts protein into useful protein for the body to use. Cobalamin or b12 is very much needed in the body because it helps make healthy red blood cells and it also helps create a fatty layer around nerve cells, which if not there can diminish brain function. Folic acid helps all the B vitamins, it is needed for basically all the normal growth and maintenance of every cell in the body. Vitamin C is the vitamin with the largest quantity removed during the pasteurization process, basically 100% of it. Vitamin C helps with collagen which basically helps hold the body together through the connective tissue joints, and muscle attachments to bone. It also helps to fix damage made to the body, without enough Vitamin C other vitamins and minerals can't do their jobs.
All 5 of these vitamins seem super essential to me, like they would be very important to keep in my diet at every turn. Yet with pasteurization their removed either partly or completely.
Pros for Raw Milk
Raw milk contains 22 essential amino acids, lactose intolerant people often have no problem digesting it, it's a complete protein, raw milk reduces allergy related conditions in 40% of kids (Internet journal of asthma). If raw milk is harvested from pasture fed/grass fed cows, in a clean environment and from a clean cow then the milk you drink should be safe. People only drank raw milk before the early 1900s when pasteurization was stumbled upon. The butterfat in it is also linked to helping the immune system and protecting against disease.
Cons for Raw Milk
The FDA is against the consumption of raw milk because they believe it puts people at an undo risk for diseases, such as TB, strep, and salmonella. If you have an already weakened immune system due to taking immune blocking medications such as when your doing chemo, you can become very seriously ill from drinking raw milk. Also, if you are not cautious about the farm and the cows your receiving the milk from you can also be exposed to mild-serious ailments. You should never drink raw milk from cows that are in confined feed given dairies which main purpose is for pasteurization. Only drink raw milk from dairies whose intention is for the milk to be raw; they have higher standards for the cows and removal of the milk. Also if you have never had raw milk and begin drinking it some people do complain of a minor or mild stomach issue for a short while during which time the body adjusts to the raw milk enzymes.
I caution the use of Raw milk, be very sure you are getting it from a reputable farmer. Also, do your own research into the matter, there are plenty of websites for you to look into. 28 out of 50 states do not even allow the selling or giving away of raw milk, so you'll have to find out what's legal in your own state.