Thanks to Dr. Kurt Harris from Archevore.com for much of the following information:

The template we use assumes we are starting with the standard american diet. I have found that steps two and three are very difficult without the immediate introduction of fats to substitute for the excess of sugar and gluten grains. Following an “eat what they ate” paleolithic diet has the flaw of eliminating dairy as not “orthodox paleolithic”.  A convenient way to start replacing an unhealthy carb intake with fat (without eating brains, liver and marrow of wild game every day) are butter and milk-fat. Remember, our goal is to develop long term success, not to recreate what cavemen ate!

This is not for everyone, but can be a positive step for many!

Take the milk most people are already drinking and ramp up the fat content. Skim milk is less than 0.5% fat by weight and so is mostly water with milk sugar or lactose, and milk protein, including casein. Whole milk is 3.2% fat by weight and has 50% calories from fat, half-and-half is about 12% fat by weight and most of the calories are therefore coming from fat. (Cream of course avoids most of the lactose and casein because it’s nearly all fat.)  The satiety you get from the increased fat will make the elimination of sugar, HFCS and white flour possible.

Cream, butter, and cheese have little to no lactose as it has been either skimmed off or consumed by fermentation.

In addition to lactose intolerance, which is very common, there can be an immunologic reaction to casein (and whey as well), the protein in milk.

Cream and butter are mostly fat of course, but both milk and cheese have casein. I do not think dairy is nearly as significant on a population basis as grain lectins, but it may be an issue. So I generally view butter and heavy cream as excellent and cheese and milk as less so. Most who have difficulty with dairy are just sensitive to the lactose, but there can be immune system issues with casein found in milk and cheeses. I believe casein serving as a molecular mimic to self antigens, and therefore causing autoimmune diseases, mainly occurs in the context of an already leaky gut. In other words, if you do not have Wheat Germ Agglutinin and other grain lectins in your diet, the casein is not likely to leak into your blood stream.  That is why I believe eliminating gluten grains minimizes the threat of dairy for most people. I believe getting to step 3 makes the milk prescription in step 2 safer in this way.

I myself consume butter and cream, half and half and occasionally whole milk – but, no surprise, I consume zero gluten grains.

Dairy is not paleolithic historically, but as a relatively ubiquitous food class, definitely helps in acheiving our goals – the evolutionary metabolic milieu of low insulin levels and mimimal toxins from modern cereal grains.