If you're allergic to dairy, lactose intolerant or you just aren't crazy about the taste of dairy milk, reach for soy milk as a comparable alternative. It generally has a longer shelf life than dairy milk, and some types of packaged soy milk can be stored at room temperature for months, which helps eliminate waste caused by food spoilage. Soy milk also has a number of nutritional advantages, although some varieties of soy milk come loaded with sugar, which can pose a health risk.
Include soy milk in your diet as a source of protein. Unlike most plant-based proteins -- which contain some, but not all, of the amino acids you need in your diet -- soy contains all nine essential amino acids. Your body assembles these amino acids into new proteins, including antibodies essential for immune system function, structural proteins that hold your tissues together, and enzymes that help your cells produce energy. Each cup of unsweetened, plain soy milk provides 7 grams of protein.
Calcium and Iron
Drinking soy milk also helps boost your calcium and iron. Your body relies on the calcium from your diet to maintain dense and strong bone tissue. Without it, your body draws on your bones as a source of calcium, which reduces your bone density over time. A cup of unsweetened plain soy milk boasts a calcium content of 299 milligrams, which contributes 30 percent toward your recommended daily calcium intake. The iron in soy milk helps your red blood vessels function properly, helping ensure that all the tissues throughout your body get the oxygen they need. Each serving of soy milk provides 1.1 milligrams of iron -- 14 and 6 percent of the daily iron intakes recommended for men and women, respectively.
Riboflavin and Vitamin B-12
Soy milk also helps you consume B-complex vitamins, and serves as an especially rich source of riboflavin, or vitamin B-2, and vitamin B-12. Getting enough vitamin B-12 in your diet helps your cells produce DNA, aids in red blood cell function and also keeps your nerves healthy. A serving of soy milk provides 3 micrograms of vitamin B-12, more than the 2.4 micrograms you need each day. The riboflavin in soy milk helps your cells produce energy, and it also shields your DNA from damage. Drinking a cup of soy milk boosts your riboflavin by 0.51 milligrams -- 39 percent of the recommended daily intake for men and 46 percent for women.
Disadvantages: Separate Fact from Fiction
Don't shy away from including soy milk in your diet out of a fear of soy -- the University of Maryland Medical Center notes that soy foods are safe for most people. The exceptions are those who have soy allergies and recent breast cancer patients. Because soy products, including soy milk, contain chemicals similar in structure to estrogen, a diet rich in soy might pose a health risk if you've recently had breast cancer, which is sometimes sensitive to estrogen. As a result, further research is needed to determine soy's safety after breast cancer.
However, some types of soy milk do have a major nutritional disadvantage because of their added sugar content. Added sugars boost your calories without offering nutritional value, and increase your risk of cardiovascular disease. Select unsweetened soy milk to minimize added sugar -- it contains just 1 gram of naturally occurring sugars and no added sugar. Chocolate and vanilla flavored soy milks, in contrast, contain 18 and 6 grams of added sugar per serving, respectively.