Ben Emanuel II
Ever wonder if soy is healthy? Read on to find out more plus a peek into the foods and products it’s in.
Soybeans are a type of legume native to East Asia. They are an excellent source of high quality protein, along with being low in saturated fat and high in dietary fiber. Additionally, they are a good source of isoflavones, phytochemicals that promote heart health and the maintenance of bone health in postmenopausal women.
Many of the health properties of soy are due to its nutrient profile. Soybeans contains all of the essential amino acids, as well as a comprehensive list of micronutrients, including: calcium, iron, magnesium, manganese, phosphorus, potassium, vitamins B1, B2, B3, B5, B6, B9, C and zinc. Fiber and essential fatty acids are also present in soy. (Asif, M., & Acharya, M., 2013)
One of the drawbacks with soybeans is that they are hard to digest. Fermentation makes them more digestible and adds flavor. It also deactivates soy’s natural phytic acid and enzyme inhibitors, which can affect mineral and protein absorption.
Edamame are green soybeans that are a whole food, commonly found in the frozen food section of grocery stores. The pods are often served boiled in water for a few minutes and then lightly salted. One cup of shelled edamame provides about 23 grams of protein.
Miso is a fermented soy food that is a strong-tasting, salty condiment often served as soup or in sauces.
Soy flour is processed from whole ground roasted soybeans. It is used to increase the protein content of breads, cakes, and cookies. Soy flour is naturally gluten free.
Soy milk is a good source of soy protein. It is made from soybeans that have been finely ground, cooked and strained. Soy milk can be highly processed with numerous additives and flavorings.
Soybean oil is a vegetable oil extracted from the seeds of the soybean. It is one of the most widely consumed cooking oils. Soybean oil is also used as a base for printing inks and oil paints.
To create soy protein powder, soybeans are ground into a meal which contains no hulls or fat. This is then processed into soy protein isolate. This protein powder can be used to make protein shakes or to add protein to other meals. Many manufacturers add additional nutrients to commercial soy protein to improve its taste, texture, and nutritional value.
Soy yogurt is made using soy milk by adding yogurt bacteria (Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus salivarius subsp. thermophilus), and sometimes sweeteners such as fructose, glucose or sugar.
Tempeh is made from soybeans that have been fermented and then formed into flat blocks. Sometimes grains like brown rice, barley, or millet are added. Tempeh has a meaty taste and is often used as a meat substitute in cooking. It can be marinated and grilled as well as added to stews and pasta sauces. Tempeh is high in protein, fiber and isoflavones. It is one of the healthiest forms of soy.
Tofu, also known as bean curd, is made by curdling soy milk (from soybeans) and then pressing the curds into soft, white blocks. Tofu is low in fat and calories, high in protein and a relatively good plant source of iron and calcium.
Other foods and products that contain or possibly contain soy:
Non-food sources of soy:
Oh No GMO
GMOs are genetically modified organisms. Their safety for human consumption is a hot topic of debate. Many European countries have banned GMOs due to the lack of conclusive data in long term studies regarding the health effects. Some studies have found that glyphosate genetically modified soybeans contain high residues of the pesticide compounds and that organic soybeans showed a more healthy nutritional profile.
Since most of the global soybean crop is genetically modified and much of it ends up in farmed animal feed, my personal preference is to choose organic for both animal and plant products until more studies can confirm long-term safety.
(Bøhn, T., et al., 2014)
Consumption of soy with isoflavones may have a beneficial effect on bone health. There was a significant decrease in bone turnover markers of resorption and formation after supplementation with 15 g of soy protein with isoflavones for 6 months.
(Sathyapalan, T., et al., 2017)
Genistein in soy activates estrogen receptor (ER)-α and ERβ and acts as an estradiol in multiple target tissues. Because estrogens increase breast cancer risk and genistein promotes the growth of ER-positive human breast cancer cells, it has remained unclear whether this isoflavone or soy is safe. Results reviewed in a study by Hilakivi‐Clarke, L., et al. 2010, suggest that women consuming moderate amounts of soy throughout their life have lower breast cancer risk than women who do not consume soy; however, this protective effect may originate from soy intake early in life.
(Hilakivi‐Clarke, L., et al. 2010)
Soy foods and their isoflavones (genistein and daidzein) are associated with lower PSA levels and a lower risk of prostate carcinogenesis. However, some studies show that dietary intake of isoflavones was associated with an elevated risk in advanced prostate cancer.
(Applegate, C. C.,et al., 2018) (Reger, M. K., et al., 2018)
Cardiovascular Disease (CVD)
Soy isoflavones may act as selective estrogen receptor modulators. Supplementation with soy protein isoflavones by women for 6 months significantly improved CVD markers including:
(Sathyapalan, T., et al., 2018)
Soybean and soy isoflavone supplements have been investigated as a treatment to relieve hot flashes and other menopausal symptoms. Some studies found that soybeans and isoflavones reduced the frequency and severity of hot flashes.
(Ju, Y. H., 2016)
In patients with subclinical hypothyroidism, soy protein and isoflavone combination has been shown to increase the risk of developing overt hypothyroidism; however, it is unclear if soy affects thyroid function in those without existing thyroid compromise.
(Sathyapalan, T., et al., 2015)
Men and Soy
In contrast to the results of some rodent studies, findings from more recent studies show that neither isoflavone supplements nor isoflavone-rich soy affect total or free testosterone levels. Similarly, a number of other clinical studies did not show that isoflavone exposure affects circulating estrogen levels in men or effects sperm and semen parameters.
(Hamilton-Reeves, J. M., et al., 2010) (Messina, M., 2010)
Tempeh Stir Fry
Silken Tofu Chocolate Mousse