Dairy gets mixed reviews nowadays. If you've done any research at all you'll find reports stating the goodness of milk and cheese, and conflicting reports that say it should be avoided for health reasons. So what is the truth? I'm not a scientist, but I am a well-red consumer. The following explanations are based on my findings over the years. I haven't cited any sources, but a search in a search engine will yield many.
Lactose Intolerance, Pasteurization, and Homogenization
A large percentage of Americans report being lactose intolerant, having an inability to break down lactose or casein that is in dairy products, and this is a main reason why you'll find evidence that dairy is possibly not meant or healthful for human consumption. But if we go back before the Industrial Era, not 200 years ago, and before pasteurization and homogenization of our milk began occuring so that milk could be widely packaged and distributed by massive dairies, we find the answer to why lactose intolerance is so prominent today.
It used to be that people either owned their own cows and got their milk fresh from the cow, or it was delivered fresh from local dairies. Nothing was pasteurized (basically, the milk is heated to destroy bacteria, but the beneficial bacteria also dies, similar to chemotherapy treatments in which the sessions destroy both good and bad cells). Nothing was homogenized. The fat percentage was not altered, everyone drank full fat milk, and the cream rose to the top. The cows from which the milk emitted went out to pasture and grazed in the fields and were collected back in the stalls to be milked in the evening.
In modern dairies there are myriad cows trapped in stalls. I wonder if they've ever visited pastures. They are fed hormones to increase their milk production and antibiotics to ward off disease that is so abounding in their close confines. Instead of a steady diet of grass or hay they are fed corn and other grains. What does this mean for the milk they produce? It means it is of far lower quality. For one, cows are not meant to eat grains. The magic of milk is that when the cow eats grass, the beta carotene and other nutrients from the grass produce a healthy, nourishing milk that is full of beneficial saturated fat. When cows are fed grain the nutritional content of the milk is different. I picture putting diesel fuel into a car that takes unleaded fuel. You are just not going to get the same performance with the wrong fuel.
This also means that traces of hormones and antibiotics end up in the milk supply. After this the less than ideal milk is sent to pasteurization, where it will lose any beneficial bacteria it had. Then it will be homogenized, and the very molecular structure of the milk fat is changed. Some argue that milk becomes indigestible to the human system at this point.
All of these things lead people to pursue alternative milks made from products like soy, almonds, and rice. Manipulating soy to make it into a milk-like product has always put me off as a health concern, and many reports confirm my fears. If you are loathe to go down this route, consider raw milk.
You may have heard about raw milk. Raw milk is simply milk that has not been pasteurized or homogenized. It does not contain casein and many lactose intolerant people claim they have no trouble digesting it. Raw milk can be difficult to find, and in a few states it is actually illegal to sell or purchase it within the state for fear of contamination. If you want to pursue raw milk and it's not illegal in your state, I suggest finding a source and even visiting the dairy to inspect it for yourself. As long as the facility is sanitary the worry of contamination is quite small.
With raw milk, all the beneficial bacteria are present, which are a boost to our own immune systems. As well, the fat in the milk is considered to be greatly healthful rather than harmful. This is a contradiction to reports that dairy fat is harmful to human bodies. I would say dairy fat is indeed harmful to our bodies if it is coming from milk and cream produced by unhealthy cows and subsequently pasteurized and homogenized.
Tips on Purchasing Commercial Milk
I am happy that I can purchase raw milk, and I drink it regularly. Neither I or my family have ever gotten ill from it, but sometimes I can't get to my supplier and I need to pick up some commercial milk for the kids' cereal. My personal rule for purchasing milk that is not raw is to find a brand that states it is hormone and antibiotic free. Next, sometimes you can find milk that has been pasteurized at a very low temperature, and this leaves at least some of the beneficial bacteria intact. Read the labels carefully.
From there I've found it quite difficult to come across milk that is non-homogenized, but if you can get it, take it! There was a dairy in my former state that sold their milk in reusable glass bottles and it was non-homegenized. This meant it had to be shaken up each time you poured it, but that was okay. So if you can get it, I suggest that. Aside from labeling, you'll recognize it because the cream rises to the top.
Now, if you can find non hormone and antibiotic free milk but it is also pasteurized AND homogenized, get a lower fat milk. In my own theory homogenized fat is harmful, so the least fat you can get the better it is for you. I would assume this is why doctors insist skim milk is healthy. In this case it is the way to go, but the fat from raw milk is actually far more beneficial than any skim milk on the market.
The bottom line is, commercial milk is potentially harmful to our bodies and likely indigestible and should be avoided.
Yogurt, Butter, Cheese, and other Dairy Products
Of course, since raw milk is so beneficial, it is ideal to purchase yogurt, cheese, butter, cream, etc. that is made from raw milk. I especially recommend using butter that is made from the milk of grass fed cows, since it is all fat. Luckily there is a nationally known brand called KerryGold butter that is produced in Ireland that is made from the milk of grass fed cows. In health stores you may find other brands of the same type of butter, and even cultured butters. It is so much more delicious than regular butter as well!
Before refrigeration, every culture in the world that has incorporated dairy would preserve it by creating cheeses, buttermilks, and yogurts. These are cultured milk products that contain a myriad of beneficial bacteria that are essential to maintain our health in the intestines. When we are not doing well in our intestines we begin to get sick with all kinds of diseases, but that's another story.
The good news is, while any dairy product is going to be best if it's from healthy, grass-fed cows and is un-pasteurized, once dairy products are cultured they at least become far more digestible to our bodies. So if you can't find or can't at this time afford raw milk yogurts, buttermilks or cheeses, I'd say as long as you're staying away from products made with hormone and antibiotic enhanced milk, you're fairly safe with them because of the culturing.
To avoid complications with cheese, I suggest either reducing your cheese intake or buying organic and raw milk cheeses.