Well, boron is back. Sort of. Today I had a conversation with Reza Naghii, PhD, a researcher at the University of Medical Sciences in Iran. Naghii and his colleagues published a study in 2010 (1) which suggests that supplementation with boron for 7 days increases testosterone. The subjects in the study were healthy, non-smoking males, 29-50 years of age (avg. ~41). For each of the 7 days, they received a capsule containing 10 mg of boron in the form of sodium tetraborate along with their breakfast.
According to the authors of the study, boron had no “major” effect on hormone levels 6 hours after supplementation. There was, however, a significant reduction in sex-hormone-binding globulin (SHBG), a protein that binds to testosterone in the blood. After one week, significant changes in hormone levels were evident. The authors explain:
“The mean plasma FT [free testosterone] concentration increased significantly from 11.83±4.60 to 15.18 ±3.07 pg/ml [approx. 28%], and the mean plasma E2 [estradiol] concentration decreased significantly from 42.33 ±16.47 to 25.80±11.25 pg/ml [approx. 39%] after one week supplementation, while DHT [dihydrotestosterone], Cortisol and Vit. D showed a non significant, but higher level at weekly post supplementation period.”
The observed increase in free testosterone certainly isn’t huge, you might say. Still, if one were able to maintain this increase over time (say, 6 months) with continued boron supplementation, might it provide some benefit? I don’t know. On a related note, I recently read a paper in which the author stated that after 35-40 years of age, men experience a 1-3% fall in “circulating” testosterone each year, by which I assume he was referring to total (including free) testosterone. If this is true, then a 28% increase might be of some value. Or not.
How does boron “work?” I’ve been told that it may increase testosterone levels by (a) inhibiting the activity of enzymes that normally break it down and/or (b) by increasing vitamin D levels (also possibly via enzyme inhibition). The latter theory is consistent with a recent study showing that Vitamin D supplementation increases testosterone levels in vitamin-D deficient men. I’ve also been told that boron works best if you have a “low” testosterone level. For instance, if your testosterone level is already in the high end of the normal range, then taking boron may not boost it any further. Until research clarifies this one way or another, you can take what I’m saying as hearsay.
Men and women taking boron might be concerned that it will increase dihydrotestosterone (DHT), something scientists refer to as a “metabolite” of testosterone. Testosterone is turned into DHT by an enzyme known as 5-alpha reductase. DHT is associated with prostate disease, hair loss and other androgen-related conditions. It makes sense to me that anything that increases testosterone will increase the levels of testosterone metabolites, DHT and estrogen included. (An enzyme known as aromatase converts testosterone into estradiol, which is a potent estrogen.) I asked Naghii to share his thoughts about this. Please keep in mind that he is from Iran and his English, while excellent, may be a bit confusing to some. I’ve edited his response slightly to make things clearer. He told me:
“Testosterone metabolites are mainly DHT, free testosterone and estrogen. In fact, testosterone is a precursor and once you increase its level, then you are expecting to increase its metabolites [DHT and estrogen] and these changes seem to be time and dose dependent. Clinically, you see the physiological effects, but sometimes it is hard to catch the exact increased levels, due to the feedback system. Therefore, higher fund [more money for studies] is needed to overcome this drawback by taking higher numbers of volunteers and sampling every week for example in a 6 weeks study.
Nevertheless, according to the result of limited studies, no undesirable increase has been noted [in DHT or estrogen] with 10-20 mg dose. [This is because] you are dealing with the production of endogenous hormones which are physiologically under controlled, [as opposed to exogenously administered hormones] which cause side effects. Some recent studies from Turkey, Korea and Japan (References are in the paper) are indicating that larger doses [of boron] create no undesirable effects on hormone levels or spermatogenesis and boron even appears to be a candidate for HRT, as well which requires further clarification.”
You may be interested to know that Futureceuticals sells calcium fructoborate (CFB), a boron-containing compound marketed under the trademarks Testosterone Advantage and FruiteX-B. CFB occurs naturally in plants. The product sold by Futureceuticals is produced synthetically. Because it is identical to the compound found in nature, it is said to be “nature-identical.”
Unpublished studies performed by Futureceuticals indicate that their CFB product can increase free testosterone levels in healthy middle-aged men. The average increase in total and free testosterone in a 6-week study was 56% and 29.5%, respectively. In a second study, total and free testosterone increased by average of 10.2% and 5.25%, respectively, 3 hours after a single dose of CFB.
As I was writing this post, I actually received an email from Naghii. In it, he talks about how boron supplementation may increase testosterone, and its potential value to bodybuilders and others hoping to benefit from it.
“I believe boron is involved in hydroxylation process which produces active form of hormones and it acts better in people with a deficiency state, e.g. aged subjects or postmeopausal women. But still I would recommend it to bodybuilders instead of steroids. It needs confirmation and deserves a research work among the bodybuilders. Limited results indicates its effect on increasing Vit d which requires hydroxylation for production and activation. In my study in a week , we found: an increase of Free T. from 11.8 to 15.18 pg/ml and Estradiol decrease from 42 to 25 pg/ml. It seems a shift from estradiol production into [the direction of] free testosterone, or higher androgenicity after one week.”