Why I Don't Drink Milk
When I did my raw foods cleanse a little over 2.5 years ago, I started really examining the foods I wanted to incorporate back into my diet once the cleanse was over. Meat, dairy, and wheat were the big three, and I ultimately decided to decrease my dairy intake by replacing cow's milk with almond milk or coconut milk whenever possible. This means I no longer drink cow's milk with my cereal, in smoothies, or in a tall glass with cookies. The only time I really crave milk, strangely enough, is when I eat a hot cookie, but I don't miss the taste of milk, so I think it's something about the comforting connotation and memory of cookies and milk. What an example of food's relation to memory and emotions, huh?
Because I primarily avoid processed and pre-packaged foods, choosing instead to make my own, I can control what goes into these foods. If I make something that requires milk, it's an easy substitute to use almond milk, which I always have on hand (almond milk, in my experience, lasts much longer than cow's milk--though this may be due to the long list of ingredients in almond milk, which I want to investigate). This doesn't mean I don't indulge every once and a while in foods with dairy--I'll still have the occasional bowl of ice cream, or eat a dessert that was prepared with milk. But by limiting the number of dairy-containing foods I consume, I reduce my dairy intake dramatically.
The great thing about today's grocery stores and food establishments, at least in North America, is the availability of milk alternatives. Most coffeeshops will offer soy, almond, coconut, or lactose-free milks for your latte, and the grocery store dairy and freezer sections are full of lactose-free yogurt and ice cream options. Because these products are made with the consumer's health and diet in mind, many are made with whole and all-natural ingredients (though you always need to check to make sure). The result is that they may be higher in fat than the popular "non-fat/low-fat/100-calorie/diet" options a little farther down the shelf, but because your body knows how to process all/most of the ingredients (which are real as opposed to chemical) in the food, they are better for you overall. If you're concerned about the amount of fat you're consuming (which is a prudent concern), it's good to keep in mind that some foods need to be eaten sparingly, or at least in moderation. Just because an ice cream is made with coconut milk and evaporated cane juice, for example, doesn't mean you should eat it any more often than you would an ice cream made of cow's milk and white sugar.
So why do I avoid/limit dairy? It comes down to the way most humans break down the lactose, or sugars, in milk. Lactose is digested with the aid of the lactase enzyme, a naturally-occurring gene in humans that breaks down lactose into absorbable glucose and galactose, which are basic sugars. The lactase enzyme lines the walls of the small intestine in the form of microvilli, which are like fingers grabbing and absorbing the nutrients of food passing through the small intestine. For most of the human population, production of the lactase enzyme decreases after two years of age. So in fact, most people are lactose intolerant (i.e., their bodies don't naturally break down and absorb lactose).
(Warning: scientificky stuff ahead. Feel free to skip this paragraph if it doesn't interest you.) There is so much research, study, and reading on this. Much of it has to do with the vast dairying culture that is present throughout the world, as a large portion of the population seems to have developed lactose persistence, something scientists point to as a niche construction of gene development, where a mutation in the LCT (lactose) gene prolongs the release of the lactase enzyme and allows adults to break down and absorb lactose. There is also history that points to the proliferation of the genetic and hereditary adaptation to long-term lactose absorption, which has a higher presence in those of European ancestry.
For me, this is a big kicker: human beings are the only species that consume milk past infancy, and we are the only species that consumes milk from another species. I have no trouble believing that we, as a culture, have adapted to digest (I use the term loosely, here) milk, just like we've adapted to digest the largely chemical- and preservative-laden foods in our food system. But that doesn't mean my body organically recognizes how to do it, likes it, or gets the most benefit from it. And the more I put into my body that it doesn't recognize or inherently know how to process, the more time and energy it takes to break down and absorb (or pass, or store--eek!) those things. And the more time and energy it takes on digestion, the less my body can focus on it's other functions (which means I have less energy, I get sick more often, I need more sleep, food, supplements, medication, whatever). By feeding myself whole, all-natural, and basic foods, I am doing myself a huge favor.
So I still get skim milk in my decaf cappuccino when I occasionally splurge at Starbucks (though this is mostly because I'm sensitive to soymilk), but by decreasing/avoiding milk and other dairy products, that rare event doesn't throw me out of whack or disrupt my body's system. For people who dread giving up dairy entirely, it's good to keep in mind that even decreasing consumption is better than the massive amounts our culture consumes on a daily basis.
For those concerned with calcium intake for bone health and how to get enough without drinking milk, there are some great studies on the effects of calcium consumption from dairy (hint: Vitamin D plays a bigger role than you think), like this one from the National Institute of Health.
Reading material: LCT gene, lactase persistence, ancestral lactose tolerance, dairying history, LCT mutation, dairy and the health pyramid