What is soy?
Soy comes from soybeans, which are legumes. Soybeans can be eaten whole or processed into soy oil, soy protein, soymilk, tofu, and fermented soy products including okara, soy sauce, and tempeh.
Why eat soy?
Soybeans are a source of complete protein, meaning they contain all of the essential amino acids found in animal meat. Therefore, soybeans are a good alternative to meat. Soybeans also contain omega-3 fats, fiber, calcium, magnesium, potassium, and B-vitamins. As an added bonus, they are cholesterol free and low in saturated fat.
Have we always eaten soy?
Soy was first cultivated in the U.S. in 1765. However, it didn’t become a leading crop until World War II. Today, the U.S. produces nearly half the world’s supply of soy. Interestingly, more soy is fed to animals than humans. In fact, about 95% of all the soy meal in the U.S. is fed to livestock.
What about soy-based infant formula?
Roughly 100 years ago, soy-based formula was used to treat diarrhea. 20 years later, it was also used to treat cow’s milk intolerance. However, it wasn’t until the 1970s that soy-based formula became commonplace. Today, soy formula accounts for nearly 25% of all infant formula sold in the U.S. The problem is that soy protein formulas can cause allergies and other intolerances. In fact, a significant amount of children with an intolerance to cow’s milk protein also develop soy protein intolerance. Thus, the American Academy of Pediatrics suggests the use of soy formulas only in cases of galactosemia or congenital lactase deficiency.
Is soy genetically modified?
A lot of it is. In 2000, more than 50% of all the soy grown in the U.S. was genetically modified, specifically as “Roundup Ready” soy. Essentially, a bacterial gene was inserted into the soy plant, which allowed the soy plant to survive treatment with Roundup.
How much soy do we eat?
In 1992, $300 million worth of soy foods were sold in the U.S. By 2009, sales skyrocketed to $4.5 billion. Where is all the soy coming from in our diet? It is present in small quantities in a vast array of processed foods including meats, bakery goods, breakfast cereals, crackers, energy bars, and even chocolate.
Is Soy Beneficial?
Soy may lower your risk of heart disease, menopausal bone loss, osteoporosis, and some types of breast and prostate cancer. In fact, the U.S. Food and Drug Administration approved a health claim stating that consuming 25 grams of soy protein per day, along with a diet low in saturated fat and cholesterol, may reduce your risk for heart disease.
Is Soy Harmful?
Possibly. Many of the health benefits found with soy are likely due to compounds called isoflavones. While these compounds seem to be helpful for many conditions, such as heart disease, they are also potentially harmful because they are plant compounds that mimic estrogen. Some researchers believe that eating too much of these estrogen-like compounds may cause reduced fertility in women, premature puberty, and disrupt development of fetuses and children.
Additionally, if you have a soy allergy or intolerance then soy is harmful to you. Soy allergy occurs when your immune system thinks the soy protein is a dangerous substance and attacks it. In contrast, soy intolerance occurs when your digestive system can’t properly break down the soy protein. Both of these conditions cause similar gastrointestinal symptoms including: bloating, diarrhea, vomiting, nausea, stomach cramping, and gas. A soy allergy, however, can cause more severe symptoms including shortness of breath, chest pain, and even death.
I am soy intolerant, so I can’t offer a favorite recipe this month. However, I have a friend who loves tofu smoothies. Here’s her favorite recipe:
1 Cup soft Tofu
1 Cup frozen mixed berries
1 Cup Orange Juice
Blend all ingredients together. Add ice to increase thickness.
Bottom line: Our daily consumption of soy is on the rise and we don’t yet know the long-term health consequence.
Dr. Sina McCullough has a PhD in Nutrition and Exercise from the University of California at Davis. She is a freelance writer and nutrition consultant (www.personalizeyourdiet.com).