It’s promoted as natural, gluten-free, low-calorie, no cholesterol and an excellent source of protein, iron and calcium. It’s also one of the most common sources of protein for those who pursue plant-based diets. But let’s be honest and bring tofu back to where it belongs…in the trash.
As early as 1963, tofu was regarded as a dependable source of vegetable protein. Unfortunately, today 99% of soy is genetically modified and sources labeled organic or non-GMO are often exposed to the same problems as conventional soy. In 2011, the USDA uncovered a plot to import fraudulent organic certificates produced by an uncertified supplier in China. These types of things are happening every year and only a fraction are being discovered. Even domestically sourced organic soybean crops are now being investigated for having GMO origins. Organic soy also does not change the toxicity of unfermented sources so abundant in the food supply.
Tofu is a highly processed form of soy that made its way into the mainstream American diet more than 50 years ago. Today, it is nothing like what was prepared in Asia and consumed by millions. Many types of tofu especially those that mock meats are similar to processed deli meats and sausages. It’s processed food and not particularly healthy in any way.
Most people stuck on the soy bandwagon are consuming far more phytate by the sheer volume through mass consumption of things like soy milk, tofu, cereals, and processed foods. It doesn’t even compare to the amount they would consume through seeds and nuts.
The effect of phytic acid on iron absorption has been thoroughly studied. As evident in a study in the American Journal of Clinical Nutrition, as phytic acid increases, it has a diminishing impact on iron while inhibiting its absorption. This applies to almost every major mineral including zinc–one of the most important minerals for the human body. Two billion people may now have zinc deficiency. Phytates bind to zinc and thereby decrease its bioavailability. Phytic acid levels in soy reduce assimilation of calcium, magnesium, copper, iron and zinc.
Most tofu is unfermented. Phytates in unfermented soy products such as tofu actually obstruct absorption of protein and four key minerals: calcium, magnesium, iron, and zinc. In their natural form, soybeans contain phytochemicals with toxic effects on the human body. The three major anti-nutrients are phytates, enzyme inhibitors and goitrogens. These anti-nutrients are the way nature protects the soybean plant so that it can live long enough to effectively reproduce. They function as the immune system of the plant, offering protection from the radiation of the sun, and from invasion by bacteria, viruses, or fungi. They make the soybean plant unappetizing to foraging animals. All plants have some anti-nutrient properties, but the soybean plant is especially rich in these chemicals. If they are not removed by extensive preparation such as fermentation or soaking, soybeans are one of the worst foods a person can eat. The net protein utilization of unfermented soy is 61 which quite low.
The most common soy (99%) sold at major grocery retailers in soy milks and processed foods such as tofu is unfermented soy. It is deadly. Unfermented soy has been linked to digestive distress, immune system breakdown, PMS, endometriosis, reproductive problems for men and women, allergies, ADD and ADHD, higher risk of heart disease and cancer, malnutrition, and loss of libido. Fermented sources of soy such as natto, miso, tempeh and some fermented tofus are likely the only types of soy that should be consumed by humans and that’s only if you can get around the crap shoot that they’re non-GMO and organic (which there is no guarantee despite labeling).
When food is eaten, digestive enzymes such as amylase lipase and protease are secreted into the digestive tract to help break it down and free nutrients for assimilation into the body. The high content of enzyme inhibitors such as trypsin in unfermented soybeans interferes with this process and makes carbohydrates and proteins from soybeans impossible to completely digest. When foods are not completely digested because of enzyme inhibitors, bacteria in the large intestine try to do the job, and this can cause discomfort, bloating, and embarrassment. Anyone with naturally low levels of digestive enzymes such as elderly people would suffer the most from the enzyme inhibiting action of soy. In precipitated products, enzyme inhibitors concentrate in the soaking liquid rather than in the curd. Thus, in tofu and bean curd, growth depressants are reduced in quantity but not completely eliminated.
Natasha Longo has a master’s degree in nutrition and is a certified fitness and nutritional counselor. She has consulted on public health policy and procurement in Canada, Australia, Spain, Ireland, England and Germany.
Source: Prevent Disease