Is soy milk good for you? What you need to know about this protein-rich, plant-based milk.

Soy milk is a creamy, plant-based drink that’s derived from soybeans. In the context of a well-rounded diet, soy milk can be an excellent source of vitamins and minerals. Of all the plant-based milks, fortified soy milk ranks the most similar to the nutritional value of dairy milk. 

In recent years, concerns over the safety of soy milk have arisen. In conversation with a dietitian, we’ll debunk some common misconceptions surrounding this nutritious, plant-based beverage, and break down what you need to know about all of the health benefits that soy milk has to offer.

Is soy milk good for you?

“That depends on your health and goals,” says Amelia Sherry, MPH, RD, CDN, CDCES, a nutritionist at Mount Sinai. “If you can’t or won’t consume cow’s milk, [soy milk] can be a good alternative.” 

Soy milk contains all of the necessary amino acids, is protein-rich, low in saturated fat, “and high in potassium and plant compounds called isoflavones, which can be good for heart health,” Sherry says. The exact nutritional value of soy milk will depend on whether the beverage is fortified with essential nutrients, and if it is sweetened or unsweetened, per Healthline. 

Soy beverages can be fortified with vitamin A, vitamin D and calcium. Fortified soy milks containing these vitamins and minerals have comparable nutritional compositions to dairy milk, per the USDA.  

Unfortified and unsweetened soy milk can be a source of vitamin B6, folate, magnesium and zinc. Each serving of sweetened soy milk tends to contain a range of five to 15 grams of added sugar, according to Healthline.

Is it safe to drink soy milk?

One of the greatest misconceptions surrounding soy milk is that it can impact estrogen and testosterone levels in men. “We don’t have any reliable evidence that the phytoestrogens, otherwise known as isoflavones, found in [soy milk] impact levels of estrogen in the body,” Sherry says. “There’s no strong evidence that soy lowers testosterone in men,” she adds. 

Another misconception is that consuming soy products increases the risk of developing breast cancer. To date, research “does not point to any dangers from eating soy in people, and the health benefits appear to outweigh any potential risk,” per the American Cancer Society. Recent evidence suggests that isoflavones (soy compounds) may actually lower the risk of breast cancer recurrence or death, according to one 2024 study.  

Is carrageenan in soy milk safe?

In recent years, concerns have been raised over the use of the carrageenan as an ingredient in soy milk. Carrageenan is an additive that's used to “thicken and stabilize the liquid,” which mitigates against soybean solids and water from separating, Sherry says. 

The reason why “some organizations are calling for more research into carrageenan’s safety [is] because of its potential to increase insulin resistance or cause problems for people with autoimmune diseases such as irritable bowel disease,” Sherry explains. 

Currently, the FDA regards carrageenan to be a safe food additive. “The small amounts of carrageenan present in [soy milk] are likely safe for the majority of adults,” Sherry says. 

“If you have concerns, carrageenan must be listed on all food labels so you can easily identify and avoid it,” she adds.

Who should avoid soy milk?

Soy is considered to be one of the “big nine” major food allergens in the US, per the USDA. The FDA and the USDA’s Food Safety and Inspection Service (FSIS) both require soy to be listed on food packaging labels as an allergen. If you have a known allergy to soy products, avoid drinking soy milk. 

Additionally, “soy can interfere with the absorption of some medications such as levothyroxine,” says Sherry. It doesn’t necessarily mean you have to avoid soy milk altogether, but if you have concerns about medicinal interactions, “you should talk to your doctor or dietitian about timing,” she suggests.

Which milk is healthier, almond or soy?

“The answer varies from person to person,” Sherry says. 

More:What does protein do for your body? Plant vs animal sources, and other FAQs answered

“If you have a soy allergy, almond would be better of the two,” she recommends. But, “if you’re a vegetarian and having trouble meeting protein goals, [soy milk] would be a better option.”

One cup of unsweetened soy milk contains 7 grams of protein. Comparatively, one cup of unsweetened almond milk contains 1.01 grams of protein, according to the USDA.