Milk is good for you, right? Doesn’t it have calcium, Vitamin D, and protein?
In an article by The New York Times entitled Got Milk? Might Not Be Doing You Much Good, the benefits of milk are reviewed. Milk has unfortunately not been found to be associated with decreased risk of hip fractures, or increased bone density. It may even be associated with increased risk of death. There is a great editorial in the British Medical Journal reviewing the data on milk (note, however, that it is behind a paywall). One of the studies the editorial cites concludes that milk, but not fermented dairy products such as yogurt, are potentially harmful to people’s health. Milk, unlike yogurt, is high in the sugars lactose and galactose. This article in Science Alert gives a simple overview of that study.
What are these sugars? You’ve probably heard of lactose, because some people are lactose intolerant, meaning they lack the enzyme, lactase, to digest milk. Instead, the bacteria in the gut breakdown lactose into glucose and galactose, and in the process, release gas, which leads to bloating and other symptoms associated with lactose intolerance. According to the study, lactose and galactose are thought to contribute to oxidative stress, inflammation, and even aging. Additionally, if you think about it, when you remove the fat from the milk, you end up with more sugar (most likely in the form of lactose) per unit of volume of milk.
Dairy is restricted or forbidden in the popular Paleo diet, which based on the idea that we should eat like our Paleolithic ancestors because that is what we were evolved to eat. I am personally not convinced by the Paleo diet, as I don’t think it makes an accurate evolutionary argument that properly takes into consideration human biological variation and adaptability- we humans can survive and thrive on a variety of foods, not just the ones supposedly consumed during the Paleolithic period. Given the results of the studies in the paragraph above, it does appear that certain dairy products, particularly fermented dairy products (yogurt, cheese, kefir, buttermilk), are good for you. Maybe it’s the bacteria, maybe it’s the lack of lactose and galactose. But that discussion is for the future! Grab some yogurt, and enjoy!