Dairy has only been consumed for the last 9,000 years or so, which is far too short a period in our evolution for us to fully adapt to it. As a direct result, many people experience severe health-problems hitw dairy:-

First of all, it's well-known that 75% of the world's population are lactose-intolerant to some extent, with at least 3% casein-intolerant, with malabsoprtion of dairy being a common occurrence:-

http://www.foodintol.com/dairy.asp

There have been one or two  international studies directly linking dairy-consumption to much higher rates of osteoporosis, with other studies showing no benefit  of dairy-consumption as regards healing of hip-fractures etc. - giving the lie to the notion that calcium-rich  dairy builds strong bones:-

http://www.ajcn.org/cgi/content/full/70/2/301A

A useful site re the link between higher rates of osteoporosis and dairy-consumption can be found here:-

http://www.youngerthanyourage.com/4/ExcessiveCalcium.htm

Dairy-consumption  has also been linked to much higher rates of heart-disease:-

http://www.ncbi.nlm.nih.gov/pubmed/9727089?dopt=Abstract

http://aje.oxfordjournals.org/cgi/content/abstract/149/2/151

and prostate-cancer, among other types of cancer:-

http://www.ncbi.nlm.nih.gov/pubmed/10383480?dopt=Abstract

http://www.youngerthanyourage.com/13/cancer2.htm

http://www.urotoday.com/browse_categories/male_infertility/high_dairy_product_intake_associated_with_an_increased_testicular_cancer_risk.html
Dairy-consumption has also been directly linked to  increased rates of dementia, depression and strokes  in the elderly, due to the excess calcium in dairy:-

http://news.sawf.org/Health/37084.aspx

http://www.sciencedaily.com/releases/2007/05/070501115230.htm

Dairy has also been linked to schizophrenia and autism:-

http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&Cmd=ShowDetailView&TermToSearch=15123503&ordinalpos=4&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum

http://paleodiet.com/autism/


Dairy, along with grains, is also heavily implicated in the rise in the incidence of autoimmune  diseases such as multiple sclerosis and rheumatoid arthritis:-

http://www.ncbi.nlm.nih.gov/sites/entrez?db=pubmed&uid=1291895&cmd=showdetailview&indexed=google

http://paleodiet.com/ms/

http://paleodiet.com/ra/

http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1505908

Then there's the issue of the extremely lopsided Calcium:Magnesium ratio of dairy(c.12:1). In Palaeolithic times, the caveman diet had a calcium:magnesium ratio was only c. 1:1 -  but our modern dairy-filled diet has on average a 4:1 Calcium:Magnesium ratio which is most unhealthy, as excessive calcium in the diet(above 1:1) ends up blocking the intake of magnesium into the body, thus leading to magnesium-deficiency:-

http://www.paleodiet.com/losspts.txt

Since magnesium is an essential component of the human body, a lack of magnesium leads onto various minor to major health-problems:-

http://www.ctds.info/5_13_magnesium.html

http://www.ctds.info/magnesium.html

There are also serious concerns about the dangerous effects of all the hormones in dairy:-

http://www.news.harvard.edu/gazette/2006/12.07/11-dairy.html

There is particular concern about the link between dairy-consumption and a higher rate of male reproductive disorders, due to the large amounts of the female hormone oestrogen , present in cows' milk:-

http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=11601881

Dairy has also been linked to a higher rate of Parkinson's Disease:-
http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&Cmd=ShowDetailView&TermToSearch=17272289&ordinalpos=49&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum

Another factor to consider is the amount of harmful opioids present in dairy(and grains and processed foods). It's a well-known fact that such opioids are highly addictive, and it is no coincidence that food-manufacturers  routinely use them in processed foods:-

http://www.karlloren.com/diet/p18.htm

http://www.forgoodnesssake123.com/Glues.html

Lastly, it's also well-known that lactose a major nutritional component of  dairy, if consumed in appreciable amounts,  inhibits the absorption of copper into the human body, thus potentially causing problems re increased rates of  heart-disease in later life:-

http://www.ncbi.nlm.nih.gov/pubmed/3357459

On an anecdotal level, it should be noted that  large numbers of raw-meat-diet-beginners tend to make the mistake of consuming large quantities of raw dairy at first, as it's an easier raw animal food to get used to than raw meat, say. This inevitably leads, over time,  to long-term problems such as magnesium-deficiency(indeed number of  long-term heavy consumers of raw dairy (eg:- Primal Dieters) have openly admitted that they take artificial magnesium supplements in order to make up for the excessive calcium-rich dairy in their diets. And also  those allergic to dairy tend to get artificial, powerful cravings for raw dairy, and often lose their taste for healthier raw animal food such as raw meats/organ-meats. Even worse, some Raw-Animal-Foodists  choose to ignore the serious health-problems caused by their body's reaction to the harmful raw dairy and try to pretend they're merely experiencing an endless series of "detoxes" and that raw dairy is a supposedly excellent detoxing food. Nothing could be further from the truth.

*It should be noted that many of those Raw-Animal-Foodists who consume raw dairy often claim that eating raw dairy, as opposed to pasteurised dairy will automatically resolve any health-problems incurred from eating pasteurised dairy, whether due to allergies or whatever. They also tend to recommend all sorts of mystic preparations such as only eating raw dairy at room-temperature, mixing raw dairy with honey or only eating A2-protein dairy etc., but invariably none of these methods work to any genuine extent for those with allergies towards raw dairy. Plus, they often tend to claim that it's impossible to experience a(lactose-intolerance-related) allergy towards raw dairy(or sometimes just towards raw butter), despite the various accounts from people  who've experienced lactose-intolerance etc.  towards raw butter etc. Unfortunately, many of the harmful aspects of dairy, such as the opioids and the excessive amounts of calcium in dairy, are as prevalent in raw dairy as in pasteurised dairy, so this is not a convincing argument at all. In short, while it's generally the case that consuming raw dairy causes  fewer problems, overall, than consuming pasteurised dairy, side-effects and health-problems related to raw-dairy-consumption are  the most frequent problems faced by Raw-Animal-Foodists when they first  start going raw. Problems with veggie-juice and raw eggs are merely secondary in frequency to raw dairy, in that regard.*