Becoming a Naturopathic Doctor was one of the best decisions I have made for many reasons, but one of them is that you certainly come across all KINDS of cool health information and rumors every day in the form of new research, new gossip, and patient questions. Today I was asked an interesting question from a patient who is taking a pea based vegan protein powder. She had read that peas can affect her fertility, and was wondering if she should stay away from it? A quick Google search showed that there is lots of support in the rumor mills for this theory, so I decided to look into it further.
Peas come in many shapes and sizes, and are generally great to incorporate into your diet. They offer a superior source of protein for anyone who is vegetarian, vegan or simply favors a plant based diet, and may be one of the best absorbed types of proteins when selecting a protein powder. When consumed in their whole food form, peas contain a healthy amount of fiber and protein, which can help balance blood sugar levels, control cholesterol levels and promote digestive function. Like many fruits and vegetables they are also packed with cancer fighting antioxidants, and have been linked in one study to a decreased risk specifically of stomach cancer. (1) Pea protein may even help lower blood pressure! (2)
So what gives? How can something that seemingly has so many health benefits have such a bad reputation when it comes to fertility? Although there are many sites claiming there is a connection between infertility and pea consumption (or that peas are a natural contraception, depending on what you are aiming for) it all seems to stem from several studies done back in 1950s and 1960s. The compound of concern in peas that may or may not cause infertility is called m-xylohydroquinone. In the first study published on this matter in 1959, available information states that a concentrated form of this compound (amount and frequency of dose if not specified), given to a large number of women and men (number of participants unknown), fertility was decreased by up to 60%, although over what time period is unknown. Unfortunately due to the age of this article, only the abstract is available online which clearly does not give enough information to draw valuable conclusions from theses alleged findings. (3)
The remaining available research has been done in rats and was conducted in 1962. Authors administered a concentrated form of m-xylohydroquinone for 30 days, and noticed no change in fertility compared to untreated rats even over this extended period of time. (4)
No published research is available in the last 50 years on the topic of peas and infertility, or m-xylohydroquinone for that matter, and thus I do not have great faith in the idea that dietary intake of peas would have a significant impact on fertility. This concept seems to have recently come up in several recent fertility books, although as outlined in this article seems to be unfounded. Although diet can play a role in the chance on conception, I think focusing on whole foods, nutrient intake and blood sugar balance is much more important than demonizing peas when it comes to getting pregnant.
- Dr. Sarah Penney, ND, MSc
REFERENCES
1. Hernandez-Ramirez, R., et al. Dietary intake of polyphenols, nitrate and nitrite and gastric cancer risk in Mexico City. Int J Cancer. 2009 September 15; 125(6): 1424–1430.
2. Dahl, W. et al. Review of the health benefits of peas (pisum sativum L.). Br J Nutr. 2012;108(1):S3-10
3. Sanyal SN. Oral contraceptive for use by both males and females.International Pallned Parenthood Federation. The Sixth International Conference on Planned Parenthood. Pg 254-257. Abstract available at: http://www.popline.org/node/476650.
4. Kar A, Bose A, Das R. Effect of m-xylohydroquinone on the genital organs and fertility of male rats. J. Reprod. Fertility. 1963;(5):77-81.
As originally written for acenutrients.com by Dr. Sarah Penney, ND, MSc