“The body can deal with soy only if eaten occasionally and in small amounts.”—Jessica Stamm, Stamm Nutrition
Sperm Health In Question
I have received an unusual number of inquiries regarding sperm health. I’m not sure what it is about the fall that makes men so urgently concerned about sperm health, but I’m happy to help answer their questions!
There were so many questions that I thought to start a series of articles about sperm health. My hope is to help those of you out there with the same questions who might be too shy to ask.
Can Sperm Interact with Soy?
One of the most alarming things I found in my sperm research—I’ve been up to my elbows in sperm research lately, thanks to you readers—is the way that sperm interacts with soy.
It keeps on coming up so I decided to focus on it for the first installment of this series of articles. Here are a few facts, supported by research, that will have you hiding from the scary spooky soy monster!
Soy Exposure Beginning in Infancy
- Soy exposure, beginning in infancy and continuing through adolescence, causes males to have “significantly higher” levels of estrogen and “significantly lower” levels of testicular testosterone.
- The supporting study was performed on rats to determine whether soy exposure changed the physical makeup of their reproductive systems, and it didn’t.
- It is still alarming to think of how many little boys start out on soy infant formula and transition to soy filler in their school lunch meat. All in the name of good health.
Foods that help improve sperm health
- Foods that improve sperm health include egg yolks and raw (or non-homogenized) milk. Soy induces “sublethal” damage to sperm, meaning it doesn’t directly kill sperm, but it gets pretty darn close!
- An interesting study on ram sperm (really, what could be more manly than sperm from a ram?) found that freezing sperm with egg yolk or milk protein made it more functional when thawed. Freezing it with soy lecithin created “sublethal damages that seriously affect sperm functionality.”
- One more reason to choose creme brûlée over soy ice cream for a romantic baby making dessert! As if you needed a reason…
No Soy Latté?
- Just a few months ago, a study done in Japan found that increased intake of soy and coffee (oh no!) was a “significant contributor to poorer semen quality.”
- Other non-dietary factors identified in the study as sperm killers (kind of like Ghostface Killah but different) included exposure to plastics, ingestion of pesticides, and increased levels of cadmium from cigarette smoking.
The Effects Are Not the Same in Everyone
It’s important to keep in mind the fact that the body can deal with soy if eaten occasionally and in small amounts. The effects are not the same in everyone.
Some men suffer extreme hormonal changes when eating even small amounts. Some vegan men use soy as their primary source of protein and face no problems with fertility, having several healthy children to prove it.
If you do decide to eat soy, please be sure it is not genetically modified (“GMO-free”). Try to stick to fermented forms such as tempeh, miso, or natto over highly-processed tofu.
Jessica Stamm obtained her Master’s in Human Nutrition from the University of Bridgeport in 2005 with subsequent board certification as a CCN via the Clinical Nutrition Certification Board (CNCB). She started her nutritional practice in Iowa and in the Summer of 2009 relocated her business to Hawaii. Jessica works with nutritional clients worldwide, teach corporate wellness programs, and also produces materials for several nutrition and food-related companies.