Along with most dairy, cheese falls into that gray area of the Paleo lifestyle. If you can’t digest it, obviously you shouldn’t eat it, but for those of us who can enjoy dairy on occasion without any repercussions, cheese can be a great option.
Cheese and Carbohydrates
One of the main reasons to avoid milk (even if you can tolerate dairy) is its high carbohydrate content, but as it ages, one of the forms of sugar (lactose) is converted into lactic acid by bacteria. This starts the curdling process, and by the end, there is very little, if any, lactose left. The longer a cheese is left to age, the less lactose (i.e. sugar) the cheese contains, making it a friendly addition to any low-carb, high-fat diet.
Nutritional Content of Cheese
Cheese is also pretty nutritious, containing all the fat-soluble vitamins of milk, including vitamin K, which is essential for maintaining healthy bones and teeth. If you can get your hands on raw, grass-fed cheese, you’ll be even better off. The pasteurization process kills a lot of the nutrients contained in the dairy, whereas the raw stuff is a nutrient-dense whole food that can absolutely be included as part of a Paleo-friendly lifestyle. Just be sure not to overdo it.
Mark Sisson has a number of recommendations on the kinds of cheese to eat and the kinds to avoid and why.