A study has linked excess soy consumption to low sperm count in men. Soy is a powerful phytoestrogen that has found its way into the average American’s diet. As soy is a versatile high-protein alternative to meat, the fact that it is cheap to produce has enabled soy to find its way into most processed foods. For those concerned about processed food, harmful endocrine disrupting chemicals such as Glyphosate is used to drench soy and other crops — and are added to processed foods and used for livestock feed.
According to a Harvard study, eating half a portion of soy protein per day can decrease sperm count in men, with the most drastic effects occurring in obese men, and may play a role in male fertility. The World Health Organization recently reported that one-in-six Americans of childbearing age suffer from infertility, with obesity being one of the main culprits.
“There have been a lot of interest in estrogen and isoflavones in particular and a potential relationship to fertility and other reproductive disorders,” said lead researcher Dr. Jorge Chavarro, a research fellow in the department of nutrition at the Harvard School of Public Health.
The estrogenic effects of soy are well-documented in the animal kingdom. Male catfish fed soy isoflavones became 100% biologically female in one study. Male monkeys became sexually inactive, aggressive but submissive loners, when placed on a soy-based diet. Genetic and neurological disorders were recorded in mice when fed soybean oil — the most commonly used oil in America — becoming a cause for concern.
“Research in animals has shown that isoflavones and estrogen can have a potentially negative affect on reproduction, including decreased fertility,” Chavarro said. “However, there is very little evidence of how these findings apply to humans,” he said.
“It’s way too early to say stop eating soy foods,” he said. “It’s not time to worry about whether you’re eating too much soy. There’s not enough information to conclusively say that. “
According to ABC News:
For the study, Chavarro and colleagues collected data on 99 men who attended a fertility clinic for evaluation. The men were asked about how much of 15 soy-based foods they ate in the past three months.
The foods men were asked about included tofu, tempeh, tofu or soy sausages, bacon, burgers, soy milk, cheese, yogurt, ice cream and other soy products like roasted nuts and energy bars.
Because different foods have different levels of isoflavones, half a serving of soy is equal to about one cup of soy milk or one serving of tofu or soy burgers every other day, Chavarro noted.
The study found that men who ate higher quantities of soy had 41 million fewer sperm per milliliter of semen compared with men who did not eat soy foods. Normal sperm counts range between 80 million and 120 million per milliliter. Although obesity could be a contributing factor, high soy consumption in men correlates with sperm levels between a third to a half of the global average.
The researchers believed that since excess visceral fat in men leads to higher estrogen levels due to increased aromatization, additional soy consumption would further reduce sperm counts due to soy’s estrogenic qualities.
“When patients are overweight, the fat tissue converts male hormones to more female hormones,” Dr. Hossein Sadeghi-Nejad, an infertility expert, said. “So, it is possible that the combination of this estrogenic source [soy] and the extra internal estrogen that is caused by the conversion of androgen to estrogen through the fat has a more deleterious effect in that group of patients.”
In a previous article, we covered the curious case of a man who grew breasts and suffered from erectile dysfunction after consuming 3 liters of soy milk per day, lending credence to Sadeghi-Nejad’s statement. Another report linked consuming more than 60 grams of soy protein per day could lead to reproductive issues in women. The occasional protein bar or processed snack won’t do much to lower sperm count. However, the combination of excess body fat and regular consumption of soy products could put you in the danger zone.
