What are Soy benefits and dangers? Soy is definitely one of the most controversial foods in the world. And it is everywhere. You can find soy in most of the processed foods, starting with chocolate (as emulsifier lecithin) to sausages, where soy protein isolates are used. Soy is the main ingredient to replace dairy and meat. It is widely used in sport supplement (soy proteins) and fast food industry (soy oil for frying).
So if it is so widely spread, I think it’s very important to know all about soy. So is it beneficial or dangerous? Join me on my research, facts only.
How to use soy?
Soybeans are legumes that originated in East Asia, where it has been grown for three millennia, but are now being produced on a large scale all over the world. Today, the world’s top producers of soy are the United States, Brazil, Argentina, China and India.
Large-scale development of soybean production and processing in the U.S. began during the 1940s and 1950s, spurred on by a rapid increase in both domestic and worldwide demand for protein meal and oil. In 1960s, the United States became a world soybean superpower and began exporting large quantities of soybeans, as well as meal and oil, to Europe and Asia *
Usage of soybeans:
- biodiesel production
- animal food
- human food
About 85 percent of the world’s soybean crop is processed into vegetable oil (using the chemical solvent hexane) and meal (which is about 50% protein). Virtually all of that meal is used in animal feed. Some two percent of the soybean meal is further processed into flours and proteins for food use.*
Soybeans must be cooked, as they are poisonous when raw. Soybeans can be eaten:
- Whole, with the immature types being called edamame
- Fermented – tempeh, tofu, miso
- Processed – oil, meal, protein isolate, soy lecithin and other
Interestingly, whole soybeans are rarely consumed in Western countries. The majority of soy in the diet comes from the refined products that are processed from the soybeans.
Because it’s cheap and has certain functional properties, oil and Alprotein have found their way into all sorts of processed foods, so most people are consuming significant amounts of soy without even knowing about it.**
Genetically modified soy
Agriculture companies grow genetically modified (GM) soybeans since 1996, and they quickly became predominant in the major soy producing countries.
Now farmers grow over 90% genetically modified soy. All the products not labeled organic or non-GMO are almost definitely genetically modified.
GM plants, such as soybean, corn, cottonseed and canola, have had foreign genes forced into their DNA. The inserted genes may come from species, which have never been in the human food supply.***
Several animal studies indicate serious health risks associated with genetically modified (GM) food (AAEM 2009),” including infertility, immune problems, accelerated aging, faulty insulin regulation, and changes in major organs and the gastrointestinal system. ***
So why to genetically modify soybeans? Early GM soybeans were engineered to be herbicide resistant (specifically to the popular RoundUpReady brand glyphosate) and were thus very popular with farmers.*
Heavy usage of glyphosate on soy is another concern. Various researches have indicated that glyphosate is cancerogenic, may be an endocrine disruptor; has been linked to liver disease, birth defects and reproductive problems in laboratory animals; and may kill beneficial gut bacteria and damage the DNA in human embryonic, placental and umbilical cord cells.****
GMO soy causes allergic reactions***
- Soy allergies skyrocketed by 50% in the UK, soon after GMO was introduced
- A skin prick allergy test shows that some people react to GMO soybeans, but not to wild natural one
- Cooked GMO soybeans contains as much as 7-times the amount of a known soy allergen
- GMO also contains a new unexpected allergen, not found in wild natural soybeans
Whole soybeans contain a range of important nutrients: large amounts of Manganese, Selenium, Copper, Potassium, Phosphorus, Magnesium, Iron, Calcium, Vitamin B6, Folate, Riboflavin (B2), Thiamin (B1) and Vitamin K.
100 g of soybeans also contains 446 calories, with 20 grams of fat, 30 grams of carbs (9 of which are fiber) and 36 grams of protein. So soybeans are a pretty good source of protein. They’re not as good as meat or eggs, but better than most other plant proteins. **
Soybeans are high in phytic acid, present in the bran or hulls of all seeds. It’s a substance that can block the uptake of essential minerals.
Be aware that the nutrient composition of soy depends dramatically on the type of food. Whole beans can be nutritious, while refined soy products like protein and soybean oil aren’t nutritious at all.
The fatty acids in soybeans are mostly Omega-6 polyunsaturated fats. This can be problematic, because too many Omega-6s in the diet can lead to inflammation and all sorts of health issues **
For this reason, it is very important to avoid soybean oil (and other vegetable oils high in Omega-6) and processed foods that contain it.**
Isoflavones. Risks and benefits
Soy contains large amounts of biologically active compounds called isoflavones that can activate estrogen (female hormones) receptors in the human body.
These isoflavones are classified as endocrine disruptors, chemicals that interfere with the normal function of hormones in the body.
This can cause reduced estrogen activity due to the isoflavones blocking the actual, more potent estrogen from binding, or it can lead to an increased estrogen activity.
These isoflavones can reduce symptoms when women are going through menopause, as well as reduce the risk of bone loss in elderly women, just like estrogen replacement therapy.**
There are also some small human studies where soy caused mild disruptions of the menstrual cycle, leading to delayed menses and prolonged menstruation.**
On the other side, some findings suggested that isoflavones could promote the growth of some cancer cells, impair female fertility, and mess with thyroid function.
The majority of recent, high-quality studies have found that soy doesn’t increase breast cancer risk, and very high consumption could even offer some protection. A PLoS One meta-analysis of 35 studies found that soy intake lowered breast cancer risk for women in Asian countries.
Eating soybean and fermented products could help protect against other types of cancer, too. Findings show that it may slightly lower the risk for gastrointestinal cancers and have a protective effect in prostate cancer survivors. Eating a high-fiber diet is also tied to lower colon cancer rates, and soyfoods like edamame and tempeh both have plenty of it. *****
Soyfoods don’t affect thyroid function in people with healthy thyroids, found a Loma Linda University review of 14 studies. But if you have an underactive thyroid, you might want to watch how much soy you eat, as it have been shown to interfere with the body’s absorption of thyroid medication—but only if you overdo it, suggests a 2016 Nutrients review.*****
Isoflavones effect on men
It is not normal for men to have significantly elevated levels of estrogen . Therefore, it seems logical that increased estrogen activity from isoflavones could have some effects on men.**
In rats, exposure to isoflavones in the womb can lead to adverse effects on sexual development in males.
Soy isoflavones may play a vital role in different male reproductive disorders and male infertility. Research published from the Oxford Journal tested the link between isoflavones and semen quality and found unfavorable results for men. The studies concluded that men who had the highest intake of soy isoflavones had a signficantly lower sperm count.******
Another study found that 40 milligrams per day of isoflavones for 4 months had no effect on hormones or semen quality.**
Many believe that soy can reduce testosterone levels, but the effect appears to be weak and inconsistent. Some studies show a small reduction, while others find no effect.**
Dangers of soy-based baby formula
Exposing infants to isoflavones by feeding them soy-based infant formula can have harmful effects.
In one study, infant girls fed soy formula had significantly more breast tissue at 2 years of age than those who were fed breast milk or dairy-based formula.
Another study showed that girls fed soy formula were much more likely to go through puberty at a younger age.
There is also evidence that soy formula during infancy can lead to a lengthening of the menstrual cycle and increased pain during menses in adulthood.
Soy is also very high in manganese, much higher than breast milk, which may lead to neurological problems and ADHD. Infant formula is also high in aluminum, which can cause all sorts of problems.**
Fermented soy may be safe in small amounts
It is true that many Asian populations have consumed soybean products without apparent problems.
In fact, these populations tend to be much healthier than Westerners, although they’ve started to suffer many of the same diseases now that the Western diet has invaded those countries.**
Asian usually consume fermented products like natto, miso and tempeh.
Fermenting degrades some of the phytic acid, although it doesn’t get rid of the isoflavones **
Natto may be especially healthy, as it also contains a significant amount of Vitamin K2, which is important for cardiovascular and bone health and many people aren’t getting enough of.
Soy benefits and dangers:our recommendations
- Avoid GMO; if it doesn’t say that soybeans are ORGANIC, you can be sure, it’s GMO. It is the best also to avoid GMO fed animals’ meat and eggs
- Avoid processed soy – oil, proteins, protein isolates, lecithin – they have no nutrition, most of the times will be GMO, highly treated with chemicals and causes health concerns
- Consume small amounts of organic fermented products – miso, natto, tempeh, as fermentation degrades some of the phytic acid
- Avoid all soybean products if you are pregnant, plan on becoming pregnant, breastfeeding
- Avoid soy infant formula – studies have shown concerning results on using it
Soy benefits and dangers