Myth: All Types Of Soy Have The Same Effect On The Body
Your body may process the natural soy in tofu, miso, and soy milk differently than the kind thatâs added to processed foods.
The soy protein isolate found in supplements, protein powders, and meat substitutes is usually stripped of nutrients, such as fiber.
âItâs also a more concentrated form of soy,â Millstine says. âSo youâre much more likely to get a high dose if youâre having protein shakes and soy hot dogs than if youâre eating edamame.â
Researchers arenât certain how large amounts of soy affect breast cancer risk. In one early study, soy supplements were shown to âswitch onâ genes that encourage cancer growth in women with early-stage breast cancer.
Experts recommend sticking with a moderate amount, or about one to two servings, of whole soy a day. One serving includes:
- Half a cup of cooked edamame
- 1 cup of soy milk
- 1 ounce of soy nuts
- 3 ounces of tofu
Myth: Eat Soy To Protect Against Breast Cancer
While eating a moderate amount of soy is fine, itâs too soon to suggest eating more to protect your breasts.
âThe results are promising, but thereâs still not enough information,â Meyers says. Experts now believe that soy isoflavones may actually block estrogen from attaching to breast cancer cells instead of spurring growth like once thought.
Meyers notes that many of the hallmark studies are done in Asian countries, where people grow up eating soy in its traditional forms. âThat may influence the way their body processes soy,â she says. âWe need to look at if having soy later in life has the same effect.â
More research also needs to be done on how much soy you get at different ages. âSoy may have more of an impact on a postmenopausal woman whoâs not producing as much estrogen as a healthy 20-year-old,â Millstine says.
Soy And Cancer Risk: Our Experts Advice
Theres a lot of conflicting information going around about soy: Is it healthy? Is it dangerous? And if its OK to eat, why do some people say it isnt?
Some of the misunderstandings come from the fact that studies in people and studies in animals may show different results. In some animal studies, rodents that were exposed to high doses of compounds found in soy called isoflavones showed an increased risk of breast cancer. This is thought to be because the isoflavones in soy can act like estrogen in the body, and increased estrogen has been linked to certain types of breast cancer.
But rodents process soy differently from people, and the same results have not been seen in people. Also, doses of isoflavones in the animal studies are much higher than in humans. In fact, in human studies, the estrogen effects of soy seem to either have no effect at all, or to reduce breast cancer risk . This may be because the isoflavones can actually block the more potent natural estrogens in the blood.
According to Marji McCullough, ScD, RD, strategic director of nutritional epidemiology for the American Cancer Society, soy foods are healthy and safe. But she advises against taking soy supplements which contain much higher isoflavone concentrations than food until more research is done.
What Are Soy Foods
Soy is one of the only plant-based food sources of complete protein. Soy is rich in fiber, potassium and magnesium. Examples of soy foods include edamame , tofu, soymilk, soybean sprouts, miso and tempeh . These traditional soy foods have been used in many cultures as reliable sources of protein for thousands of years. More recently, processed soy protein has been added to a variety of foods, such as frozen meals, soups, protein powder drinks, and snack bars.
Does Soy Increase The Risk Of Breast Cancer
If theres one solid conclusion from all the data on soy and breast cancer, its that eating moderate amounts of soy foods very likely does not increase the risk of breast cancer. The majority of high-quality studies and analyses have found that soy foods do not increase risk, even when eaten at levels much higher than those typically seen in the U.S.3-4
How We Got It Wrong:
Avoidance messages mainly stemmed from the misunderstanding about potential effects of phytoestrogens and hormone-sensitive cancers, and we didnt have good data from research with cancer survivors. But now studies of survivors of breast and prostate cancer show no harmful effects, and potential for soy foods playing a beneficial role as part of a healthy diet.
Myth: If You Have Or Had Breast Cancer Avoid All Soy Foods
Just as eating a moderate amount of whole soy doesnât make you more likely to get breast cancer, it also doesnât seem to raise your risk for recurrence.
âStill, Iâd recommend that breast cancer patients avoid soy supplements,â Millstine says.
In one report, researchers analyzed data from diet surveys completed by more than 9,500 American and Chinese women. Those who said they ate the most soy were 25% less likely to have their cancer return compared to those who had the least.
Some experts worried that soy might interfere with breast cancer drugs that lower estrogen levels, such as tamoxifen. But the same study showed that soy also protected against recurrence in patients who took tamoxifen.
The soy foods that the study included were tofu, soy milk, and fresh soybeans. As you might expect, the Chinese women ate far more of it than those in the U.S. The results still held when the researchers considered that fact.
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The Pros And Cons Of Soy Protein Isolate
No doubt, SPI is a super high-protein substance. And that’s exactly why vegetarians or vegans, and those allergic to cow’s milk, may use products with SPI, says Richards.
But unfortunately when it comes to SPI, it’s not as simple as: it’s high protein so it’s healthy. That’s because the process the soybeans go through in order to create the high-protein product is controversial.
“The extraction process often leaves behind residue from chemicals and metals like hexane or aluminum,” says Valdez. So if you consume SPI you’re likely noshing on at least some of these “leftovers”. While he says the amount of metal you’ll encounter from SPI is unlikely to be toxic, it’s generally considered good practice to limit the amount of metals in your diet where possible because in high levels they can be toxic. And things like gasoline fumes, quick-drying glue, spray adhesives, contact cement, arts and craft paints, and stain removers all expose us to these not-so-savory chemicals on a daily basis, according to Valdez.
“Another thing that adds to the SPI controversy is that they are genetically modified foods,” says Richards. This shouldn’t be surprising: at least 90 percent of the soybeans grown in the United States are genetically modified. So of course most SPI is, too!
Can Eating Soy Cause Breast Cancer
There is no shortage of claims on the internet that certain foods can cause cancer. For example, you may have read or heard the myth that eating soy can increase your risk for breast cancer. But is it actually true? Here, we discuss where this idea comes from, what the science says about soy and cancer risk, and what to know about incorporating soy into your diet.
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Is Soy Safe For Patients With Breast Cancer
When it comes to eating soy foods, there are a lot of myths about whats safe for cancer survivors and patients in cancer treatment.
As a breast cancer survivor and senior clinical dietitian at MD Anderson, Christie Siebel is passionate about debunking misinformation so patients get the nutrients they need to stay healthy.
Siebel shares this advice for patients and survivors who seek to avoid soy.
Soy foods are safe for patients with cancer
Siebel stresses that soy is generally safe to eat. Soy is a great alternative to animal protein to include in your daily diet, she says. Theres no reason to avoid eating soy.
Soy contains phytoestrogens the plant form of hormone estrogen. Because the names sound similar, Siebel says there has been hesitation around eating phytoestrogen, especially among patients with breast cancer and other types of cancer that are hormone-sensitive.
For many breast cancer patients, treatment involves blocking estrogen to prevent cancer cells from forming.
Though they sound similar, these hormones arent the same, and eating phytoestrogens doesnt affect the estrogen found naturally in your body.
Soy foods may reduce your risk of cancer
Research suggests eating soy foods may reduce risk of cancer recurrence even in patients with estrogen receptor-positive cancer. Soy isnt bad for you, and it may actually be beneficial for cancer prevention, Siebel says.
Thats why I try to eat soy every day, says Siebel, who carries the BRCA gene.
What Did The Present Study Find
This study of over 1 million women from 21 different cohorts found that dairy products, overall, are unlikely to increase breast cancer risk, and that fermented dairy products may lower risk, especially of harder to treat estrogen receptor-negative tumors, explains , Senior Scientific Director, Epidemiology Research, at the American Cancer Society, and one of the researchers on the study.
Concerns about dairy and breast cancer were largely put to rest. The researchers found null or very weak inverse associations between the dairy foods studied, calcium , and the risk of developing overall or estrogen receptor -positive breast cancer.
Further, the researchers found that certain dairy foods, such as yogurt, ricotta cheese, and cottage cheese are associated with a weak reduction in the risk of breast cancer.
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Straight Talk About Soy
The Takeaway: Soy is a unique food that is widely studied for its estrogenic and anti-estrogenic effects on the body. Studies may seem to present conflicting conclusions about soy, but this is largely due to the wide variation in how soy is studied. Results of recent population studies suggest that soy has either a beneficial or neutral effect on various health conditions. Soy is a nutrient-dense source of protein that can safely be consumed several times a week, and probably more often, and is likely to provide health benefitsespecially when eaten as an alternative to red and processed meat.
Soy is exalted as a health food by some, with claims of taming hot flashes, warding off osteoporosis, and protecting against hormonal cancers like breast and prostate.
At the same time, soy is shunned by others for fear that it may cause breast cancer, thyroid problems, and dementia, though these claims have not been substantiated.
Whether published in a popular press article or a well-designed clinical study, some debate about soy remains. As a species within the legume family, nutrition scientists often label soy as a food with potential for significant health benefits. However, due to contrary research that suggests possible negative effects of soy in certain situations, there has been a hesitancy to wholeheartedly promote soy.
Thus, there are many factors that make it difficult to construct blanket statements about the health effects of soy.
|Unfermented soy foods|
Myth: All Soy Foods Raise Your Risk For Breast Cancer
Thereâs no need to banish tofu and edamame from your diet.
âFor years, soy got a bad rap because of its isoflavones,â says Marleen Meyers, MD, director of the Perlmutter Cancer Center Survivorship Program at NYU Langone Medical Center.
âSo there was a fear that soy could act as estrogen in the body and stimulate cancer cells,â Meyers says. âIt was spread on blogs, and people would tell each other to avoid soy.â
But a steady stream of studies showed that a diet high in soy didnât increase the chances of developing breast cancer and may even reduce that risk.
In one study of more than 73,000 Chinese women, researchers found that those who ate at least 13 grams of soy protein a day, roughly one to two servings, were 11% less likely to develop breast cancer than those who got less than 5 grams.
âIn Asian cultures, where people eat a lot of soy from a young age, there are lower rates of breast cancer,â Meyers says. And in those societies, people still eat soy in its traditional forms.
Meanwhile, another analysis of eight studies showed that those who got the most soy isoflavones — about the amount in a serving of tofu – were 29% less likely to get the disease compared to those who got the least.
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Does Soy Prevent Heart Disease
The FDA says that 25 mg of soy, along with a healthy diet, can reduce LDL and may help prevent health disease. However, the AHA says that it is impossible to eat enough soy to make any difference. Kaayla Daniel said that soy is actually linked to heart problems. Dr Mark Hyman said that soy is certainly better for your heart than chicken nuggets or other alternatives. The general rule of thumb that Dr Hyman offered is If it grows on a plant then eat it, and if it is made in a plant skip it. Dr Oz said that at the end of the day, in small portions, soy is a good low fat protein source and a great substitute for higher fat protein. I have to say that this segment of Dr Ozs show did nothing to alleviate my fear of all of the negative things I have read lately about health issues related to soy, so for now at least, I will be avoiding soy. What about you will you be skipping soy or continue eating it? Leave a comment below!
Is Isolate Protein Harmful
Many people can take whey protein without experiencing any side effects. It can cause digestive issues in those who are lactose intolerant or those who are allergic to cows milk, in addition to the irritation caused by lactose intolerance. If you have any side effects, you can either use a non-dairy or whey protein isolate.
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Is It Safe For Survivors
Studies of pre- and post-menopausal women suggest soy isoflavones may have a protective effect against breast cancer. Population studies indicate that soy consumption in survivors of breast cancer may be linked to decreased recurrence and greater overall survival. A 2017 study looked at more than 6,200 American and Canadian women with breast cancer. These women filled out surveys about what they ate and other lifestyle habits. Those women who ate the highest amounts of isoflavones had a 21% lower risk of having died from any cause, compared to the women who ate the lowest amount of isoflavones.
Whole Soy Foods Vs Other Sources
The positive research surrounding soy, health and breast cancer comes primarily from populations eating whole food forms of soy rather than concentrated supplements. Therefore, whole soy foods such as edamame, tofu and soy milk are safe and can be part of a healthy diet. However, concentrated sources of soy, including soy pills, powders and foods containing soy protein isolate, are not recommended for women with estrogen-positive breast cancer.
Because soy is high in fiber and low in saturated fat and sodium, it can be a great alternative to animal protein. There are many ways to enjoy soy as the centerpiece of a meal or a side dish. Add lightly steamed soybeans to a salad, snack on dry roasted edamame as a snack, or marinade and grill tofu for a main dish.
Learn more about our oncology nutritionist by visiting Integrative Medicine or calling 757-594-3099.
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Try To Avoid Isoflavone Extracts
Dr. Roesch does advise women to avoid soy isoflavone extracts, especially in large doses.
And as a general rule youre better off getting your nutrition through food sources than through supplements.
When youre taking doses of isoflavones from a vitamin store that can be several hundred times higher than what you would ingest from eating tofu or drinking soy milk, that could be a potential problem, she says.
Whether youre concerned about your risk or if youre high-risk for breast cancer its always best to make sure to talk to your doctor about everything you put into your body, she emphasizes. Together you can cut through any misinformation and identify what works best to keep you healthy.
The Real Truth: Does Soy Cause Breast Cancer
A university student walked into my office one afternoon and asked me how she could increase her protein intake. As a vegetarian, she was worried about not getting adequate amounts of recommended nutrients. I listed several suggestions such as nuts, seeds, legumes, beans, and lentils, and I also mentioned that tofu or any soy products are great options.
They are one of the few vegetarian options that consist of a complete protein. This means that any soy product contains all nine essential amino acids that are required by our bodies and are only available through our diet. I could sense her concern because she then asked, Doesnt eating too much soy cause breast cancer?
With breast cancer being the leading cause of cancerous death among women, it makes sense to wonder does soy cause cancer, and to be aware of breast cancer causes. Soy is found in many foods, especially in Asian cuisine. If youve ever eaten tofu, tempeh, miso, edamame, or most vegetarian burgers and meats, then youve definitely consumed some variety of a soy product.
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Milk And Breast Cancer: Is There A Link
A recent study concludes that women who drink greater amounts of milk might have an increased risk of developing breast cancer than those who drink little or no milk.
According to the American Cancer Society, in 2019, there were around 268,600 new cases of breast cancer among women in the United States.
Over the years, scientists have uncovered a number of lifestyle-related risk factors for breast cancer these include alcohol consumption, higher body mass index, and lower levels of physical activity.
Many scientists believe that there may also be nutritional risk factors, but as the authors of a recent study explain, Results have been inconsistent for virtually all nutritional factors to date.
Two food groups that have received a fair amount of attention are soy and dairy. Their impact on breast cancer has proven difficult to pinpoint.
increase breast cancer risk.
However, because individuals who consume more soy are likely to consume less dairy, and vice versa, untangling the relationship has proven challenging.
Unperturbed, the authors of a recent study published in the International Journal of Epidemiology set out to look for links between milk and soy consumption and breast cancer.
To investigate, the authors delved into a unique dataset created as part of the Adventist Health Study-2 they used data from 52,795 women aged 30 or older.
When they analyzed the effect of dairy, however, they found a significant interaction. The authors concluded: