What Is Soy?

Tofu, tempeh, soybeans, edamame, soymilk

Verywell / Anastasia Tretiak

Soy is a product that comes from soybean, a legume that is prevalent in East Asia. It is found in many foods including milk, tofu, and processed foods like breads and cereals. Soy is most commonly eaten as a plant protein as it has all the amino acids that act as the building blocks of protein.

It’s also considered a good source of calcium, fiber, potassium, magnesium, copper, manganese, and polyunsaturated fats like omega-3 and omega-6. In addition to whole foods, soy is available in supplement form including tablets and powders.

Does Soy Offer Any Benefits?

The benefits of soy is a topic that is widely debated and even the health benefits that have been discovered only minimally improve a person’s health. The latest research reviewed by the American Heart Association recently concluded that soy does not influence heart health, as previously believed. Some studies have shown that adding soy to your diet may help lower cholesterol as well as reduce the risk against certain types of cancer.

The biggest benefits of soy come when they are eaten as a replacement for foods like red meat and other options high in saturated fat. Substituting soy over these foods may lower LDL cholesterol slightly, as well as reduce blood pressure.

In alternative forms, soy supplements that contain isoflavones may reduce the severity and frequency of hot flashes that are associated with menopause.

In the case of soy supplements, there’s not enough research that has been conducted to determine any health benefits aside from easing menopause symptoms.

Possible Side Effects

Long-term use of soy has not been studied sufficiently enough, but as long as you don’t have a soy allergy, eating whole soy foods in moderation (a few times a week) will not have any side effects. Its nutritional profile can help increase the amount of protein and decrease the consumption of saturated fats, which can improve overall health.

Despite estrogen-like actions some of the isoflavones (otherwise known as phytoestrogens) found in soy, it is not currently believed that soy products increase the risk of gynecological cancers in women. There is also some evidence that consuming soy-based foods may actually decrease the risk of breast cancer, especially in women who live in Asian countries, where soy consumption is higher than in the United States. 

There is also no harm in men consuming soy products in moderation. While both men and women produce estrogen, men produce less amount of this hormone.

Bowl of soybeans
Verywell / Anastasia Tretiak

Dosage and Preparation

When it comes to whole soy products, the following food sources are high in nutrients including protein, vitamin B, iron, and fiber:

  • Edamame: Prepare by boiling in water for 15 to 20 minutes.
  • Soymilk: Add to smoothies or use as a replacement to milk for those who are lactose intolerant or sensitive.
  • Tempeh: Marinate and grill or cut into slices and sauté for three minutes on each side.
  • Tofu: After pressing for 20 to 30 minutes to drain the water, cut into cubes and brown in a skillet for one to two minutes on each side. Toss with your favorite dressing, sauce, or marinade.
  • Whole Soybeans: Rinse and drain beans before placing them on a baking sheet in the oven at 350 degrees Fahrenheit. Roast for 30 to 45 minutes or until golden and crispy.

Textured soy or vegetable protein, which is most often used as a meat replacement, is a type of soy product made from approximately 50% soy protein, soy flour, or other soy concentrate but also likely contains wheat, oat, or other ingredients and therefore is not considered a whole source of soy.

What to Look For

When choosing healthy soy foods, it’s important to read the labels before you make a purchase. Processed foods with soy protein isolate are stripped of most of their nutrients and often combined with unhealthy additives. Soybeans themselves in the whole form may be altered. According to the United States Department of Agriculture (USDA), over 90% of soybeans in the United States are genetically modified.

Fermented soy products will be more digestible and can increase mineral and protein absorption in the body due to the process fermented foods go through.

If you’re looking for a soy supplement to combat menopause symptoms, talk to your healthcare provider about the best choice for you. A supplement with soy isoflavones will mimic estrogen-like actions and may be able to help.

Other forms of soy, such as soy powder which can be added to smoothies, are convenient for their longer shelf life as well as being a portable source of protein. Just be aware that many of these contain soy isolate and other additives, so it’s best to use them in moderation.

A Word From Verywell

Many people who follow vegan or vegetarian diets may eat soy more frequently as a meat substitute and source of protein. Although it’s perfectly safe to eat in moderation, if you’re worried about your soy intake, it’s best to discuss this with your healthcare provider. They will be able to provide alternate sources of protein for your specific dietary restrictions and if needed, refer you to a nutritionist for further counseling and resources.

1 Source
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. American Cancer Society. Soy and Cancer Risk: Our Expert's Advice. April 29, 2019.

Additional Reading
  • Soy. National Center for Complementary and Integrative Health website.

  • Confused about eating soy? Harvard Health Publishing website.

  • A Guide to Foods Rich in Soy. University of California San Francisco website. 

  • Soy. American Institute for Cancer Research website.

  • Soy Foods and Health. TeensHealth from Nemours website.

By Colleen Travers
Colleen Travers writes about health, fitness, travel, parenting, and women’s lifestyle for various publications and brands.