Milk does a body good, but organic milk might do it better. In addition to coming from happier cows (they're given access to fresh air and pastures), organic milk and dairy products are defined as much by what isn't in them as what is. Here are the top three reasons to go organic.

1. No bovine growth hormone> Organic dairy cows are not given recombinant bovine growth hormone (rBGH). This hormone causes cows to increase milk production but may also pose a health threat to the animals and to humans. Dairy products from cows treated with rBGH show higher levels of IGF-1, which is a factor in the growth of breast, prostate, and colon cancers, according to the Center for Food Safety.

2. Free of harmful pesticide residue> Organic dairy cows eat an all-organic diet, which minimizes their exposure to pesticides. Studies have associated repeated exposure to pesticides—which are fat-soluble and passed to humans through the fat in dairy products—with an increased risk for cancer.

3. Less risk of antibiotic resistance> Organic dairy cows are not treated with antibiotics. The antibiotics given regularly to most cows can be passed to humans through dairy products, and prolonged exposure can lead to resistance—meaning an antibiotic may not work during an actual illness.