Lacto-vegetarians avoid all meat products, but they do drink milk or consume milk-based products. Many lacto-vegetarians simply love milk too much to abstain from it. Some claim that the milk industry is kinder to animals, so they still feel ethical in their decision. If you consider yourself a vegetarian for ethical reasons, yet still consume milk products, it's time for a rude awakening.
In order for a cow to produce milk, she must be pregnant. This means that dairy cows usually give birth to one calf a year. For seven months of their pregnancy, they are encouraged to produce milk by fattening up on high-energy, high-protein animal feed. Some cows produce 100 times more milk than is natural in the wild, due to the abnormal concentration of nutrients in their body. This leads to rapid calcium depletion, which leads to osteoporosis and other skeletal problems.
So what happens to the calf? Well, the veal and milk industries go hand-in-hand. The calf is immediately caged up and fed an iron-deficient milk substitute. The cage is too small for the calf to turn around, resulting in soft, tender flesh. The iron deficiency leads to anemia, which leads to the pale, tender flesh that is veal.
Nearly half of the cows in the milk industry suffer from mastitis. Their udders swell up and become infected, producing pus that is secreted along with the milk. This problem has been exacerbated by the recent widespread implementation of Bovine Growth Hormone, which is metabolized into Insulin-like Growth Factor, a human carcinogen. This Monsanto-engineered hormone allows cows to produce 15% more milk than usual, which puts additional stress on their udders. This means that most milk has a little pus contamination, but hey, it's pasteurized, right?
Because of their constant exposure to feces, cows often suffer from Johne's disease, which is caused in part by the bacterium Mycobacterium paratuberculosis. This bacteria is nearly genetically identical to the agent responsible for the very symptomatically similar Crohn's disease in humans, Mycobacterium tuberculosis. This bacterium does not die easily under heat stress, and many suspect that most incidences of Crohn's disease can be directly linked to milk consumption. This is nearly impossible to prove, unfortunately. The bacterium's resilience to heat can be demonstrated, as contaminated samples of pasteurized milk have been found in London, in a frequency that varies depending on the month of the year. Strangely enough, as is the case with Mad Cow disease, no confirmed cases of contamination have occurred in the USA.
Most cows don't survive for more than 3-4 years before they are too weak and lame to be profitable. At this point they are ground up into lower-grade beef. They aren't sold as whole cuts of meat, because they are weak, bruised, and frail. Cows in the wild can easily live 20-25 years.
Up to 70% or more of the world's population cannot even consume cow's milk after childhood, due to a missing lactase enzyme that is necessary to handle lactose. I think this should serve as evidence that dairy is not a "necessary food group," or an essential element of the "food pyramid."
Personally, I consume my fair share of milk-based products, but I figured for those who aspire to be "true" vegetarians for ethical reasons, this information would be useful. I'd like to be able to call myself a vegetarian someday, but I simply am not ready to make such a drastic change. However, I try to minimize my consumption by drinking rice milk (soy milk's good too, but I tend to be wary about the possible health effects of prolonged phyto-estrogen consumption), using Smart Balance instead of butter, and buying organic cheeses whenever economically feasible. Rice milk and soy milk substitute well in recipes, although there's nothing like real skim milk when making cappucinos.