You may have heard that you should not eat soy if you are at risk for it breast cancer. But you’ll see headlines saying it prevents the disease. So what is the truth?
Distinguishing fact from fiction can be tricky, even for health-savvy people.
It’s important to know the real deal, especially now that soy is more common in the American diet.In addition to traditional edamame, tofu, tempeh, and miso, soy is a popular low-fat food source protein. It is present in soy milk, meat substitutes, cerealsbaked goods, energy bars, etc.
Should you avoid these foods or eat more? The easiest answer is to think about the “whole” – as close to natural as possible – so you don’t get too much.
For greater clarity, learn the truth behind these five common myths.
1. Myth: All soy foods increase the risk of breast cancer.
There is no need to exclude tofu and edamame from your diet.
“For years, soy has had a bad reputation for its isoflavones,” said Marleen Meyers, MD, director of the Perlmutter Cancer Center Survival Program at NYU Langone Medical Center.
These phytochemicals are structurally related to Estrogen. up to Chest Cancers are sensitive to estrogen (or, as doctors say, “estrogen receptor positive” or “ER positive”), which means that estrogen promotes their growth.
“So there are concerns that soy acts as an estrogen in the body and stimulates cancer Cells,” Meyers said. “It spreads on blogs and people tell each other to avoid soy. “
But a steady stream of research shows that a diet high in soy does not increase the chance of developing breast cancer This risk can even be reduced.
In a study of more than 73,000 Chinese women, researchers found that those who consumed at least 13 grams of soy protein About one to two servings a day were 11% less likely to develop breast cancer compared to those who ate less than 5 grams.
“In Asian cultures, where people eat a lot of soy from a young age, breast cancer rates are lower,” Meyers said. In these societies, people still consume soy in its traditional form.
Meanwhile, another analysis of eight studies showed that people who ate the most soy isoflavones — roughly the equivalent of a serving of tofu — were more likely to develop the disease than those who ate the least. Sex was 29% lower.
“Whole soy foods are safe as part of a healthy diet,” says Denise Millstine, MD. Integrative Chinese and Western Medicine Mayo Clinic in Scottsdale, Arizona.
2. Myth: All types of soybeans have the same effect on the body.
Your body may process the natural soybeans in tofu, miso, and soy milk differently than the soybeans added in processed foods.
soybean protein Isolates found in supplements, protein powders, and meat substitutes often remove nutrients like fiber.
“It’s also a more concentrated soy,” says Milstin. “So if you have protein shake And soy hot dogs instead of edamame. “
Experts recommend sticking to a moderate amount or about one to two servings of whole soy per day. One serving includes:
- 1/2 cup cooked edamame
- 1 cup soy milk
- 1 ounce soy nuts
- 3 ounces tofu
Myth 3: Eating soy can prevent breast cancer.
While it’s okay to eat soy in moderation, it’s too soon to recommend eating more to protect your breasts.
“The results are promising, but there’s still not enough information,” Meyers said. Experts now believe that soy isoflavones may actually prevent estrogen from attaching to breast cancer cells, rather than stimulating growth as once thought.
Meyers pointed out that many of the landmark studies were conducted in Asian countries where people grew up eating traditional forms of soy. “It could affect the way their bodies process soy,” she said. “We need to see if eating soy later in life has the same effect.”
More research is needed on soy intake by age group. “Soy may have more of an effect on postmenopausal women producing less estrogen than healthy 20-year-old women,” Milsteen said.
4. Myth: If you have or have had breast cancer, avoid all soy foods.
Just as eating moderate amounts of whole soy doesn’t make you more likely to develop breast cancer, it doesn’t seem to increase your risk of recurrence.
“However, I still recommend that breast cancer patients avoid taking soy supplements,” Milstin said.
In a report, researchers analyzed dietary survey data completed by more than 9,500 U.S. and Chinese women. Those who said they ate the most soy were 25 percent less likely to develop cancer than those who ate the least.
Some experts worry that soy may interfere with breast cancer drugs that lower estrogen levels, such as Tamoxifen. But the same study showed that soy also prevented relapse in patients taking tamoxifen.
The soy foods included in the study were tofu, soy milk and fresh soybeans. As you might expect, Chinese women eat a lot more than American women. When the researchers took this fact into account, the results held.
5. Myth: Soy only affects estrogen-sensitive breast cancers.
While it is true that soy isoflavones play a larger role in estrogen receptor-positive breast cancer, early research links it to a reduced risk of other diseases Types of Breast Cancer.
The findings come from a study of 756 Chinese women with breast cancer and about 1,000 other women without breast cancer. All women answered questions about their diets, including how much soy they ate. Those who said they ate more soy were less likely to develop breast cancer than those who ate the least.
This finding does not prove that soy can prevent breast cancer in any woman. Other things may be involved.
“More research needs to be done,” Meyers said. “In general, people who eat more soy are likely to have healthier lifestyles.”
Stay tuned to see if this proves to be helpful for everything, whether you eat tofu regularly, pour soy milk over your breakfast cereal, or snack on edamame.