If you're lactose intolerant, concerned about the environment or you just aren't into the taste of cow's milk, you can reach for soy milk as a comparable alternative. Made from soybeans or soy flour, this pick is one of the more popular milk alternatives on the market.
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.
Consider these pros and cons before you swap your go-to glass with soy milk.
Read more: Is Eating Soy Actually Bad for Your Health?
The Health Benefits of Soy Milk
1. Soy Milk Packs Protein
Try including soy milk in your diet as a source of protein. Soy protein can help lower levels of LDL, or bad cholesterol, according to the National Center for Complementary and Integrative Health. Each cup of unsweetened, plain soy milk provides 7 grams of protein, according to the USDA. For reference, a glass of two-percent dairy milk contains 8 grams 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.
Are You Getting Enough Protein?
2. It Doesn't Increase Risk of Breast Cancer
It was once thought that soy foods — because of their isoflavones, a phytoestrogen — can increase your risk of breast cancer. This belief has since been refuted, according to the American Cancer Society.
A February 2020 study published in the International Journal of Epidemiology adds to this consensus finding that drinking soy milk is not linked to an increased risk of breast cancer and may actually help protect against it.
3. It Contains Calcium and Iron
Drinking soy milk also helps boost your calcium and iron intake. 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 can reduce your bone density over time.
One cup of unsweetened plain soy milk boasts 301 milligrams of calcium. This contributes close to 30 percent toward your recommended daily calcium intake of 1,000 to 1,200 milligrams, according to the National Institutes of Health.
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, contributing to the recommended daily intake of 8 milligrams for men and 18 milligrams for women.
4. It Boasts Riboflavin and Vitamin B12
Soy milk also helps you get more B-complex vitamins and serves as an especially rich source of riboflavin (vitamin B2) and vitamin B12. Getting enough vitamin B12 in your diet helps your cells produce DNA, aids in red blood cell function and also keeps your nerves healthy.
One cup of soy milk provides 2.7 micrograms of vitamin B12, which is more than the 2.4 micrograms you need each day. The riboflavin in soy milk helps your cells produce energy and shields your DNA from damage. Drinking one cup of soy milk boosts your riboflavin by 0.5 milligrams — close to 50 percent of the recommended daily intake.
You Can Also Buy Shelf-Stable Soy Milk
Unlike cow’s milk, you can find some soy milks in the non-refrigerated section of your grocery store. Aseptic packaging is used and you’ll find them with other shelf-stable milk alternatives, typically in the “natural foods” section of your supermarket. The aseptic packaging has a 12-month shelf life and once it’s opened, it must be refrigerated and consumed within a week.
The Disadvantages of Soy Milk
1. Soy Milk Allergy
Don't shy away from including soy milk in your diet out of fear of soy — as noted above, soy foods are safe for most people. The exception is those who have soy allergies.
According to Food Allergy Research & Education (FARE), soy is one of the top nine food allergies. It can be a difficult ingredient to avoid because soy is commonly used in many processed foods such as soy lecithin and soybean oil. If you're allergic to soy and looking for another non-dairy milk alternative, consider trying oat milk, coconut milk, almond milk or flax milk.
2. Added Sugars
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 can increase your risk of heart disease and type 2 diabetes.
Select unsweetened soy milk to minimize added sugar — the unsweetened stuff contains just 1 gram of naturally occurring sugars per cup and no added sugar. Chocolate- and vanilla-flavored soy milks, in contrast, contain around 20 and 7 grams of added sugar per serving, respectively.
Read more: Does Eating Soy Mess With Your Hormones?
- USDA National Nutrient Database: SILK Unsweetened, Soymilk
- National Center for Complementary and Integrative Health: Soy
- National Institutes of Health, Office of Dietary Supplements: Calcium
- National Institutes of Health, Office of Dietary Supplements: Iron
- National Institutes of Health, Office of Dietary Supplements: Vitamin B12
- USDA National Nutrient Database: Vitasoy, Soy Drink, Chocolate
- USDA National Nutrient Database: Vitasoy Light Vanilla Soymilk
- American Cancer Society: "Soy and Cancer Risk: Our Expert’s Advice"
- International Journal of Epidemiology: "Dairy, Soy, and Risk of Breast Cancer: Those Confounded Milks"
- Soyfoods Association of North America: "Soymilk"
- Food Allergy Research & Education (FARE): "Food Allergy Essentials, Common Allergies"