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The FDA wants to pull its support of the health claim that eating soy protein may help reduce the risk of heart disease. The agency proposed the change last fall, citing evidence that questions whether there's any real benefit to heart health. If the FDA goes through with the move, then food makers will no longer be allowed to market soy products with the claim that they can help your heart. But soy won't hurt your heart, and soy does have other benefits. "It's high in polyunsaturated fats, fiber, vitamins, and minerals, and low in saturated fat. Natural soy products — like tofu or edamame — could replace red meat and other animal sources of protein higher in saturated fat," says dietitian Kathy McManus, director of the Department of Nutrition at Harvard-affiliated Brigham and Women's Hospital. One caveat: some soy products contain estrogen-like chemicals that could have adverse effects. So, stay away from soy isoflavone supplements and foods made with textured vegetable protein and soy protein isolate, found in many protein powders and nutrition bars. Still, McManus says it's okay to eat whole soy foods — like soy milk, edamame, and tofu — in moderation, several times per week.
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FAQs
The most common side effects of soy are digestive upsets, such as constipation and diarrhea. Soy may alter thyroid function in people who are deficient in iodine. Current evidence indicates that it's safe for women who have had breast cancer or who are at risk for breast cancer to eat soy foods.
What is the controversy with soy? ›
Proponents of soy claim consuming it can decrease one's risk of heart disease, diabetes, and hormonal cancers (like breast cancer). Detractors claim consuming soy increases one's risk of developing breast cancer, thyroid diseases, and fertility problems in both men and women.
What does the Mayo Clinic say about soy? ›
It was once thought that soy foods increase the risk of breast cancer. However, eating a moderate amount of soy foods does not increase risk of breast cancer — or other types of cancer. A moderate amount is one to two servings a day of whole-soy foods, such as tofu, soy milk and edamame.
Does soy raise estrogen levels? ›
According to a handful of studies, soy consumption may have a link to raising serum estrogen in humans (3), and potentially causing thyroid disorders (4). Animal studies have also suggested potential male infertility and breast cancer associated with soy consumption.
Why is soy not recommended? ›
However, some worry about soy's potential downsides, including its GMO content, possible estrogen-like effects, and long-term influence on growth, digestion, sexual maturation, thyroid health, and breast cancer risk. Currently, few of these concerns are backed by strong science. However, more research is needed.
Why does soy have a bad reputation? ›
Soy contains isoflavones, chemicals that look like estrogen on a molecular level. Because of the similarity between isoflavones and estrogen, people have worried that eating lots of soy could be similar to having higher estrogen levels in your body.
Why do men avoid soy? ›
Soy contains isoflavones, which are converted in the body to phytoestrogens, similar to human estrogen that occurs naturally in both men and women. Theoretically, a high isoflavone intake could stimulate production of estrogen and decrease production of testosterone, with one result being enlarged breast tissue.
Are soy products inflammatory? ›
Soy products contain several compounds with anti-inflammatory properties like genistein and daidzein which reported to act through different pathways.
Is soy bad for the thyroid? ›
Treatment for hypothyroidism usually includes taking the thyroid hormone medicine levothyroxine (Levo-T, Synthroid, others) every day. Research has shown that soy can make it harder for the body to absorb that medicine. But people who have hypothyroidism don't need to avoid soy completely.
Why cut soy out of diet? ›
The reason why cutting soy from your diet is usually a good idea, is because naturally you will be cutting out a lot of processed foods from your diet. These processed foods also often contain refined sugar so you are also in turn eliminating sugar from your diet, which offers even more health benefits!
Unsweetened soy milk is the closest match nutritionally, plus you get a few grams of healthy fats that you won't get from skim milk. Almond milk — while not unhealthy — is less nutrient dense, especially in terms of its limited protein content.
How much soy is too much for a woman? ›
How much soy is recommended? Can too much soy be harmful? Numerous clinical studies have found that daily consumption of up to 50 grams of soy protein is not only safe, but may also be effective in improving risk factors for chronic disease such as some types of cancer, diabetes, and cardiovascular disease.
What are the negative effects of soy? ›
When taken by mouth: Soy is commonly consumed in foods. Dietary supplements containing soy extracts are possibly safe when used for up to 6 months. Soy can cause some mild stomach and intestinal side effects such as constipation, bloating, and nausea.
Is soy bad for your gut? ›
As you can see, soy is generally very beneficial for overall gut health. However, it might cause some digestions for certain people. More on that below. If you suffer from IBS or have had a history of SIBO or other digestive issues, you may be familiar with the low FODMAP diet.
What are the symptoms of too much estrogen? ›
Signs of too much estrogen in females include:
- weight gain.
- headaches.
- decreased sex drive.
- fatigue, depression, or anxiety.
- fibroids (noncancerous tumors) in the uterus.
- tenderness or fibrocystic lumps in your breasts.
- light or heavy menstrual bleeding or worsening of premenstrual syndrome (PMS)
Soy products contain several compounds with anti-inflammatory properties like genistein and daidzein which reported to act through different pathways.
Should men avoid soy? ›
The abundance of research and soy's inclusion in the USDA Dietary Guidelines confirm soy is a healthy, nutritious choice for men (and women) of all ages.
