Dan Buettner, National Geographic fellow and bestselling author of The Blue Zones, identified the five places in the world where people live the longest and investigated similarities in their diets and lifestyle behaviors. On his website, he writes that beans (including soybeans) are a “cornerstone” of all five Blue Zone diets that offer myriad health benefits.
Humans must consume nine essential amino acids to build muscle, support immune function and digestion, as well as maintain many other important functions. Soy contains all nine essential amino acids, making it a complete plant-based protein source.
A cup of soy milk contains about 8 grams of protein. In comparison, a cup of dairy milk contains approximately 8 grams of protein, too.
Soy milk and other soy-based products like tofu are naturally high in B vitamins, potassium and magnesium. Soy milk is often fortified with other essential vitamins and minerals, including calcium, vitamin D, B12 and iron, all of which are important for a healthy diet.
Soy is a reliable source of unsaturated fats, which can help balance cholesterol levels and lower a person’s risk of heart disease. A collection of studies that tracked over 74,000 people for nearly 30 years found higher intake of soy and isoflavones—especially when consumed in the form of tofu—to be associated with lower risk of coronary artery disease[3].
A small 2021 study in Menopause showed that a plant-based diet including soybeans helped reduce the occurrence of hot flashes in participants by 79%[4]. A larger 2015 meta-analysis also found phytoestrogens helped significantly reduce the occurrence of hot flashes without any significant negative side effects[5].
Eating soy products like soy milk, tofu and edamame may help reduce the risk of certain cancers, including breast, prostate and gastric cancers, according to experts at the Dana-Farber Cancer Institute. Additionally, a study in The American Journal of Clinical Nutrition that followed over 9,500 breast cancer survivors for seven years found soy intake to be associated with a 25% reduction in tumor recurrence[6].
Lastly, a 2022 review of 18 randomized, controlled studies in the Journal of Clinical Medicine concluded that soy isoflavones are effective in slowing down bone loss in postmenopausal women, thereby reducing the risk of osteoporosis[7].
If you still have concerns about soy or would like to try other kinds of plant-based milks, you have lots of options. Almond, rice, oat, coconut and cashew milks are all widely available. Like soy milk, many of them are fortified with essential vitamins and minerals, and they all have different flavors and consistencies to suit a range of tastes.
For most people, especially those with lactose intolerance, soy milk can be a wonderful alternative to dairy milk.
The overwhelming consensus in the research is that you can rest easy consuming soy milk and giving it to your son. It’s a healthy option with multiple benefits. Just make sure to choose a brand that’s fortified with essential vitamins and minerals and low in added sugar. Then you two can raise a glass to good health and enjoy.