Milk, as well as milk products, contains several essential vitamins and minerals as well as macronutrients such as fat, protein and carbohydrates. Milk and other dairy products prevent osteoporosis, cavities and other ailments. It helps to fight infection, increases energy, and protects the stomach from harsh chemicals and spicy foods. According to the Dairy Council of California, milk contains sodium, potassium, phosphorus, thiamin, and vitamins A and C, calcium and phosphorus, but little to no vitamin D, iron or magnesium, unless it is fortified.
There are several varieties of milk including whole, skim, 1 and 2 percent, dried, raw, fortified, organic, evaporated, condensed and buttermilk. Whole milk has 3.5 percent fat by weight. Skim milk is whole milk with all of the fat removed, while 2 percent milk has 2 percent milk fat, while 1 percent milk has 1 percent milk fat. Dried milk has the water removed, leaving a powder, and dried milk can also be whole, skim or reduced fat. Nonfat dry milk and fluid skim milk essentially have no significant amounts of vitamins and minerals unless it is fortified.
Butter, usually made from fresh whole cow's milk, contains vitamins A and D, but is high in concentrated saturated fats that can cause cholesterol buildup in arteries. Butter comes from churning cream or milk, and the color can range from almost white to a dark yellow, depending on the type of feed eaten by the cows giving the milk. Commercially, you will often see annatto or carotene added for color to give the butter a pale yellow shade.
Cheese is a milk-based product made by separating the curd, or milk solids, from the whey or water part of the milk. Most cheeses contain protein, milk, milk fat, calcium, phosphorus, vitamin A and riboflavin. The taste, texture and density vary, depending on how long the cheese has been aged, what animal it comes from, and the animal's diet. Pasteurization, fat content, and the type of bacteria used for processing also play a factor in taste, texture and density. Mass-produced cheese is usually aged with vinegar or lemon juice to quicken the "aging" process. Cheese is also made with buffalo, goat or sheep's milk.
Another popular milk-based product is yogurt, which is milk that has been fermented by a mixture of bacteria causing the milk to curdle into a custard-like consistency. Made with whole, reduced or fat-free milk, yogurt is made by adding a "starter" bacterium such as Lactobacillus acidophilus or other bacteria cultures. These cultures give yogurt its signature sour taste. According to the Dairy Council of California, yogurt contains sodium, vitamins A, B-12 and C, folate, calcium, magnesium, zinc, phosphorus and traces of iron.