Is Soy Safe to Eat?

 

Vegetarianism is on the rise, and more of us are eating soy. But is soy actually safe to eat? Let’s explore…

So many of you have sent us soy-related questions, so today we’re going to share some good old evidenced-based information so that you can decide if soy is right for you.

So what exactly is soy?

• Soy comes from soybeans and it’s used to make tons of food products in the market like oils, tofu, soymilk, soy sauce, tempeh, and more.
• The reason it’s so popular among vegetarians is because it’s considered one of the most complete plant-based sources of protein.
• Tofu, which is big in the vegan world, soaks up whatever flavors and spices you cook it in, and can resemble the consistency of some animal-based products (like cheeses, meats, and poultry).
• This can be especially helpful for someone who is making the transition into veganhood, but finds it hard to leave behind animal-based food products.

Here are three soy rumors we’ve come across:

1. Soy has estrogen, which causes breast cancer.
2. Soy causes early puberty.
3. Soy makes men grow breasts.

Where does the controversy come from?

• Well, soy naturally contains phytoestrogens, which have the ability to act like estrogen in the body. Phytoestrogens are plant-derived compounds found in a variety of foods.
• Soy has a significantly higher content of phytoestrogens when compared to other foods. High levels of estrogen in the body have been linked with breast, endometrial, and uterine cancer. However, it’s important to note that soy influences estrogen activity in the body- not estrogen levels.
• A lot of the soy controversy has come from research done on rats, where rats injected with more phytoestrogens could be at an increased risk for breast tumors. There have also been numerous studies with rats that indicate just the opposite effect.  
• Also, a lot of these animal studies involve very concentrated high-dose forms of phytoestrogens- which usually doesn’t resemble how humans typically consume soy.

What does human research tell us?

• Research done on humans has shown that soy has an insignificant effect on breast cancer, and some studies have even shown that soy can actually protect against certain types of cancer and heart disease.  
• Soy is relatively new to us in the states, but there are various countries in Asia that have been eating soy within the context of a traditional diet since forever, and there has not been evidence of harm.
• See the links below for more information to studies, research, and articles, for those of you who want to nerd up and look into the evidence.

And the bottom line?

• Although some animal studies have shown inconclusive results when it comes to cancer and soy, studies in humans have not shown any significant harm from eating soy foods.
• Also, although soy has been shown to offer health benefits, this doesn’t mean that you need to eat pounds of soy for breakfast, lunch, and dinner or start popping phytoestrogen supplements.

How much soy can I safely eat?

• Stick to a maximum of 2-3 servings per day. Also aim for high quality soy products.
• By this I mean organic and minimally processed things like tofu, edamame, and organic soy milk are all good options.
• Try to stay away from soy cheeses, soy burgers, soy energy bars, imitation meats, and other soy products that are packed with crappy additives.

Useful Links:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3074428/

http://www.ncbi.nlm.nih.gov/pubmed/24586662

http://vegetariannutrition.net/docs/Soy-Safety.pdf