Category Archives: soy debate

Soy and breast cancer … there’s more to the story

istock_000014130416xsmallSoy is certainly a controversial subject. And if you rely on soy as a dairy or protein substitute, you’ve undoubtedly heard and read about conflicting information regarding its health effects.

Could your daily soy lattes up your risk of breast cancer or lend a protective effect? So far, the research has been conflicting. While some studies have shown that soy can increase tumor growth at the cellular level, other research has found that soy may actually have a protective effect. However, most of what we know about this link comes from epidemiological studies (looking at broad population data), which have not been able to find a clear cause-and-effect link between soy and breast cancer.

Now, a new study published in the JNCI: Journal of the National Cancer Institute directly compared women who took soy supplements with women who took a placebo to determine what effect soy would have on the expression of genes associated with breast cancer.

The researchers looked at 140 patients who had been recently diagnosed with invasive breast cancer. In the 2-3 weeks before their surgery (either a mastectomy or lumpectomy), these women were given either soy supplements (the equivalent of about four 16 oz. glasses of soy milk or four large servings of tofu) or a placebo every day. “The hypothesis was that soy food for a limited period of time could influence the behavior of already established breast cancer,” says study co-author Jacqueline Bromberg, M.D., Ph.D., breast medical oncologist and researcher at Memorial Sloan Kettering.

After a few weeks, they found that some women in the soy group had high levels of genistein, a metabolite of soy, while the women in the placebo group did not. And interestingly, patients with high levels of this metabolite saw an increase in the genes associated with tumor growth. However, it’s important to note that the tumors were not actually growing better in these women.

Basically, taking a huge amount of soy in a short period of time led to changes in gene proliferation for some women with invasive breast cancer. But importantly, this didn’t lead to an actual change in the appearance or growth of a tumor, explains Bromberg. While the researchers definitely saw changes in the expression of these genes, they don’t know if this would lead to even greater changes if the women had been taking soy supplements for longer than 2-3 weeks.

So does that mean you should limit soy or avoid it completely if you have breast cancer?

Not necessarily. Like many things, soy seems to be safe in moderation, and there is definitely research showing it’s protective effects against a variety of cancers, including breast cancer. That said, this study does suggest that high amounts of soy may have an effect on women who have already been diagnosed. Bromberg notes that normal amounts of soy are probably fine for women with breast cancer, but she strongly advises against taking soy supplements. Moderation in a healthy diet is key, she says.

“Our study simply says that [after taking] large amounts of soy for a short period of time, a subgroup of patients who had high levels of the soy metabolite genistein had an increase in the expression of genes involved in the growth of tumor cells,” says Bromberg. “But that did not translate to an increase in actual growth.”

FoodFacts.com knows that many in our own community have had questions about the health benefits of soy vs. possible negative health effects. This new information does help to put some of those questions to rest. The advice certainly isn’t foreign — moderation in our dietary habits is always for the best.

http://www.today.com/health/latest-soy-breast-cancer-what-you-need-know-2D80192077

The Great Soy Debate!

soy-foods
Many active or athletic vegetarians look to soy as a reliable way to get their daily protein requirements. Soy is also becoming a popular item on the health food shelves. But there is a cloud of controversy surrounding this new star in the grocery aisle. Here are some of the issues that have created what some are calling “the great soy debate”.

Soy products, made from the soybean, have been eaten for thousands of years in Asia, and have always been traditionally prepared. Typically, soybeans are soaked for long periods, then often fermented or slowly boiled and eaten with animal proteins. Vegetarian travelers to Asia often find themselves unexpectedly staring at a “vegetarian” tofu dish containing pork or egg. This is because, in addition to long soaks, slow boils and fermentation, animal proteins help improve the digestibility of this ancient legume. These methods of cooking and eating soy turn off the anti-nutrient qualities of the phytic acid found in soybeans; phytic acid can block our body’s ability to break down the protein in the soy. Studies of Asian eating patterns have found that no more than 2 – 3 tablespoons of soy products are typically eaten per day.

Nowadays, soy is one of North America’s top three genetically-modified (GM0) foods, next to wheat and corn. Animals raised for meat consume up to 90% of U.S. soy crops. Since most soy is genetically-modified, that means huge tracts of land are being plowed, watered and soaked with insecticides, herbicides and pesticides, mainly to support the meat industry. Most soy products on the market today are also made from this genetically-modified soy.

If you are eating soy that has been prepared quickly, or not alongside animal protein, you may be causing undue stress on your digestive system. Anti-nutrients in the soy may be blocking absorption of protein and other minerals your body requires such as calcium and especially zinc. This is particularly problematic for vegetarians who generally consume less zinc due to a lack of meat in their diets, which is an adequate source of zinc for omnivores.

A big concern in the soy debate is that the isoflavones contained in soy may pose a threat to women, children and to thyroid health in general. These isoflavones are found in high concentration in soy milk, soy protein isolate and soy infant formulas.

Most doctors already advise pregnant women against consuming too much soy, while this possible health threat is being further studied. There is also heated debate over whether the goitrogens contained in soy (and other foods like broccoli, cauliflower and cabbage) increase the risk of thyroid disease. These goitrogens are said to block or suppress hormones that would normally circulate in our bodies and this can lead to thyroid disease, growth problems, immune system and menstrual cycle issues. Again the thyroid disease risk is mostly a concern for vegetarians who do not eat sea vegetables, because meat eaters get the thyroid-supporting mineral iodine in their diet through fish, thereby balancing out any negative effects of the goitrogens.

All of this might sound like reason enough to avoid soy. Even the FDA is monitoring the issue, although they initially approved the soy industry’s request for health claims. “FDA continues to monitor the debates about the relative safety of these individual soy components and the scientific research that will eventually resolve them,” says the Center for Food Safety and Applied Nutrition.

However, there are some very good reasons to seek out soy products. As an alternative to dairy, a glass of soy milk contains no saturated fats and is rich in polyunsaturates (Omega 6s) that are good for our health. A glass of soy milk also contains less total fat and generally fewer calories than a glass of whole milk. Beware the flavored soy milks on the market which are filled with sugar and calories. Organic, and non-GM soy products also contain none of the antibiotics and hormones that may be found in conventional dairy products.

Soy products may be good for heart health, and this is why the FDA gave it the green light as a health product in the first place. However, some scientists are now disputing this claim. They state that the reason for study participants’ improved cardiac health was that soy products replaced or reduced the amount of potentially artery-clogging foods like red meats and dairy products in their diets.

There are no doubts that eating more legumes is a very good way to increase your intake of fiber, polyunsaturated fats and also a good non-animal source of protein. But to be safe, pregnant women and those with thyroid disease should probably avoid eating soy products, or at least try to reduce them in the diet.

People with digestive problems should look for soy products that are prepared by soaking overnight or longer. You can find this out by going to manufacturers’ websites or calling their toll-free customer service line. It’s good practice to ask questions of our food providers; whether they be farmers at the market, restaurant managers or manufacturers, they should always be able to answer our questions about food quality or safety. Also, look for soy products that are low in isoflavones such as tofu or soy nuts or the beans themselves prepared traditionally. Soy milks and especially soy protein isolates will have higher concentrations of isoflavones, unless they say so otherwise on the label. Watch out for calorie-rich flavored soy milks with added sugars. Even “natural” flavored soy milk often has sugar added. Alternatives to soy milk (for vegans) are almond milk, rice milk and there are some delicious grain milks on the market. Lactose-intolerant dairy product lovers can sometimes find lactose-reduced yogurts and milk products, as well as rice-milk frozen desserts.

Wherever possible try to get organic non-GMO soy, which also tends to be processed in a more traditional manner. If you’re looking for alternative non-animal sources of protein, don’t forget all the other legumes which also should be soaked overnight before cooking, and whole grains such as brown rice and quinoa.

Ultimately, we need to think carefully about what we eat, now that we live in a world where we do not grow or raise our food in our own backyards. It’s our responsibility to make informed choices about the food on the grocery store shelves. Many of the packaged foods we find there will be quick and convenient, but not necessarily the best ingredients for our optimal health.

Article provided by Caroline Rechia