Yea, I know it's a basic question.
I have read Robb Wolf's book The Paleo Soultion and he sort of glases over this subject as he says "would just be repeating" himself, but I'd still like to know.
So can anyone tell me what the specific problems with dairy are? What is in it exactly that is so bad? How is it so different compared to human milk that it causes problems?
Note: The phrase "Because Dairy isn't Paleo" is hereby a banned answer - Science only please ;)
Dairy - or milk at least - contains three components that are not found in other foods: lactose or milk sugar, whey (a protein) and casein (yet another protein).
Some people are lactose intolerant, which means they no longer produce the enzyme lactase to break down milk sugar. This then ferments in the intestines and causes digestive distress. Even if you are not lactose intolerant, drinking white sugar water (skim milk) just doesn't make sense as the fat in milk is where some of the best nutrition is (vitamins A/E/D/K/CLA etc). Whole or raw milk may be appropriate for hard gainers, but it comes with a price (insulin spiking, weight gain that may not be all muscle).
Whey doesn't seem to be an issue for most people, but I have heard of people who are allergic to it (not sure why).
Casein is the protein that peeps are down on (even T Colin Campbell, which makes me suspicious). Casein causes loosening of tight junctions, which is good when you want to lactate - it makes lactation possible. The problem is when it gets to the intestines it can also loosen tight juctions causing leaky gut issues (allowing proteins to enter the blood stream directly, which causes all sorts of havoc). However, if you have a functioning stomach with a normal amount of hydrochloric acid (not taking a PPI inhibitor, for example), the casein protein should be cleaved at least once by the stomach acid and should not cause any problem whatsoever. But it can be an issue.
This is why some paleos say no to dairy even in addition to the "We are not adapted to it" argument. And why other paleos stick to high fat dairy like cream, ghee and butter, which have little of these three unique molecules.
Personally, I just avoid milk (although I did a raw experiment last month and found that it made me more likely to be hypoglycemic) and enjoy everything else, including cottage cheese. (Gasp! - tell T Colin Campbell to send an Oncologist pronto!)
Chris Kresser put together an excellent post about this.
He makes the important distinction between pasteurized, commercial dairy and the raw, grass-fed variety. Many people who experience problems with the former do not with the latter.
Oh, so you don't like the normal phrase? Awww....
Well, it depends. Some people are intolerant of dairy. That's a food allergy. It can also cause auto-immune issues. I know that Robb Wolf goes on a negative stance, while Kurt Harris (I'd give you a link -- but the site is down) is more of a pro-dairy stance (as long as you don't have issues with it).
If you want it from the source, Robb Wolf and Matt Lalonde talk about in Robb's podcast #68. Podcast: http://robbwolf.com/2011/02/22/the-paleo-solution-episode-68/ Show notes: http://robbwolf.com/wp/wp-content/uploads/2011/02/the-paleo-solution-episode-68.pdf
The main issues seems to be the lactose and casein, which some people can't tolerate. Lactose is removed with going to high-fat, so some people can tolerate heavy whipping cream and butter when they can't tolerate regular milk.
For me personally, I know that I can't tolerate dairy. I won't go into detail, but it isn't fun. I can, however, eat butter and heavy whipping cream without issue.
A lot of people with gluten sensitivities have the region of the microvili where the lactase production is done blocked by way of atrophy. After gluten is removed, this over time should heal. But reintroducing milk should be like starting working out as an obese person. Go slow! It'll take time to adjust. That may mean some inflammation at first (gasp!). See where you're at in a few weeks and evaluate.
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