Soybeans in their various forms are an excellent source of protein for both men and women looking to eat less meat. Beyond being a complete protein, soy is a good source of other nutrients such as omega-3 fatty acids, iron, fiber, and magnesium.
Soy has been consumed for thousands of years so why is it receiving so much negative attention in recent years? I’m sure many of you have heard that soy will lead to “man boobs” also known as gynecomastia. I’m here to tell you this is not true. Much of the anti-soy propaganda is based on bad science and quite likely fueled by the animal agriculture industry since soy foods may pose a threat to business.
Gynecomastia is the swelling of the breast tissue in boys or men. This is caused by an imbalance of the hormones estrogen and testosterone.
It’s normal for this to occur in infants due to the effects of the mother’s estrogen.
This also occurs in some boys going through puberty due to natural hormonal changes.
The occurrence of gynecomastia peaks again between the ages of 50 and 69 due to hormonal changes. The condition often goes away on its own when things are back in balance through lifestyle changes.
According to the Mayo Clinic, there are a number of things that cause gynecomastia, none of which are soy consumption. Let’s just look at a few of these.
1. Medications
Certain medications such as anti-androgens used to treat prostate enlargement, anabolic steroids, anti-anxiety medications such as diazepam, chemotherapy, and anti-ulcer medications.
2. Alcohol
Thanks to several studies on the matter, it’s well established that alcohol inhibits testosterone production. Anyone who consumes alcohol, especially moderate to heavy drinkers, should be aware of this fact since this reduction of testosterone production could further imbalance the testosterone to estrogen ratio.
3. Obesity
Because fat cells contribute to estrogen production, excess weight can further imbalance sex hormones in men.
4. Certain health conditions
Kidney failure, liver conditions, hyperthyroidism, and malnutrition are some of the health issues that can lead to gynecomastia. This is because proper hormone levels are disrupted in all of these situations.
So, let’s get back to soy.
Soy contains very weak phytoestrogens (phyto means plant). Many point to this fact and make the assumption that this will increase estrogen/decrease testosterone in the body. Not so. I’d like to point out that many commonly consumed foods contain phytoestrogens. This includes apples, pomegranates, carrots, yams, rice, sesame seeds, oats, flaxseed, and coffee. Yet no one is freaking out about these foods. Again, this points to the anti-soy rhetoric being pushed by the animal agriculture industry.
What does the science say?
A 2010 meta-analysis of fifteen placebo-controlled studies on soy was done. It concluded that that the “data indicate that isoflavones [tpyes of phytoestrogens] do not exert feminizing effects on men at intake levels equal to and even considerably higher than are typical for Asian males.”
It showed that soy foods do not alter the levels of bioavailable testosterone concentrations in men and had no effect on sperm concentration, count, or motility.
There is an interesting study that many people point to to argue against soy. I’m not even sure it’s worth bringing up but in the name of transparency, let’s talk about it. It is an unusual case of a 60-year-old male patient with gynecomastia. Notice that he is in the perfect age range for gynecomastia to occur as previously mentioned. During an interview with the man, it was discovered that the man consumed 3 quarts of soymilk daily and had for some time. That’s at least 12 servings of soy a day for months and months. This is beyond a moderate to high intake of soy so this is not a normal case! It’s not surprising that such an unbalanced diet may have contributed to problems.
This case should not be misinterpreted to show that moderate servings of 2-3 servings of soy a day are unsuitable for men or any other family member. There is enough solid research that shows that soy is a healthful and beneficial food to consume. Research shows that soy consumption is linked with a reduction in prostate cancer risk in men. So eat up, boys.
Soybeans, just like any other food, should be part of a balanced diet full of a variety of other health-promoting plant foods.
Tofu, tempeh, miso, soymilk, and edamame are all great ways to eat soy. I encourage my clients to consume soy in these whole or minimally processed forms much more often than the overly-processed versions such as fake burgers and hot dogs
The moral of the story for you men out there: enjoy your soy, bra not required!
Sources:
https://www.mayoclinic.org/diseases-conditions/gynecomastia/symptoms-causes/syc-20351793
https://www.nejm.org/doi/full/10.1056/NEJM197610072951501
https://www.ncbi.nlm.nih.gov/pubmed/20378106
https://www.ncbi.nlm.nih.gov/pubmed/18558591
you have a great blog here! would you like to make some invite posts on my blog?
http://kinesiologie-kempf.de