If you do a little research on vitamin E and testosterone, you might come to two opposite findings. One is that vitamin E supplementation raises testosterone. The other is that vitamin E supplementation lowers testosterone. What’s worse than conclusions on a matter like this not just being incongruent, but at complete odds with one another?
Do we merely choose to believe the findings for which we have a bias?
Vitamin E has been shown to reduce estrogen levels. This can raise testosterone in men whose levels are blunted by the female hormone. It’s also been shown to protect cells against lipid peroxidation – the exact type of oxidative assault that reduces testosterone production over time.
So why are there reservations among ‘experts’ when it comes to vitamin E and testosterone? Let’s take a closer look, first at exactly what is vitamin E, then at the two seemingly conflicting studies often cited in regard to vitamin E and testosterone.
Vitamin E: What is it exactly?
Back around 1922, two scientists discovered a group of fat soluble compounds essential to human and animal health that they classified as the fifth so-called “vitamin.” It was isolated in pure form in 1935, then broken down in structure and synthesized in 1938. Now what we call “vitamin E” are actually several compounds that fall under the categories of tocopherols and tocotrienols.
There are four classifications of tocopherols: Alpha, Beta, Gamma and Delta (α, β, γ, δ).
There are four classifications of tocotrienols, also Alpha, Beta, Gamma and Delta (α, β, γ, δ).
As shown in the image below, the difference between the tocopherol and tocotrienol molecules is that tocotrienols have three double carbon-hydrogen bonds along their “tales” (side-chains) whereas tocopherols do not.
The difference among the classification of α, β, γ, and δ of each form are the placements and numbers of methyl rings on the far left side of the molecular structures.
These subtle distinctions among the different forms of tocopherol and tocotrienol molecules might be important in the context of vitamin E and testosterone. They might also be important in terms of vitamin E and general health. That’s because studies revealing negative effects of vitamin E supplementation have purportedly been done with one form of tocopherol absent the balance of the other molecular forms.
According to Dr. Ray Peat, much of the early research on vitamin E was centered on its importance in cardiovascular and reproductive system health. He claims that research demonstrated it very effective in preventing the clotting diseases of pregnancy, along with protecting against the toxicity of estrogen. His strong opinions on the importance of vitamin E and an alleged shift in the scientific community’s focus in its regard can be summed up in the following quote from his website.
“In the 1940s, the official definition of vitamin E’s activity was changed. Instead of its effectiveness in preventing the death and resorption of embryos, or the degeneration of the testicles or brain or muscles, it was redefined as an antioxidant, preventing the oxidation of unsaturated oils.”
Personally, I’ve assumed vitamin E’s power in preventing degeneration of reproductive system organs is due to its antioxidant protection against the oxidation of unsaturated oils. Obviously, Dr. Peat is alluding to even greater initial importance having been attributed to vitamin E. But even simply as a defense against lipid peroxidation, this group of compounds might play a crucial role in preserving and boosting natural testosterone.
The point is that early research on vitamin E revealed its positive effects on the reproductive system. I think this bolsters its credibility as a potential testosterone preserver/booster.
Vitamin E and Testosterone: Positive Study
Back in 1982, a Japanese study demonstrated significant boosts in testosterone levels in both animals and humans as a result of vitamin E supplementation. The study also showed that, at least in the case of Wistar rats, a deficiency in vitamin E results in suppressed activity at the top of the pituitary-gonadal axis. The experiment showed that subpar levels of vitamin E led to significantly lower luteinizing hormone (LH) and follicle stimulating hormone (FSH).
The study rats were divided into three groups. One was a control group that received regular feed. A test group was fed a diet deficient in vitamin E. Another test group was fed a diet supplemented with vitamin E. The study went on for seven months, which would obviously translate to anywhere from 15 to 20 years of human life.
The results: The vitamin E deficient group experienced a big reduction in pituitary gland weight. Probably as a result, the LH and FSH (signaling hormones from the pituitary) were significantly lower in tissue and decreased in plasma in this group compared to the control. However, these animals showed only a small reduction in both tissue and plasma testosterone.
In the vitamin E supplemented group, the LH and FSH levels were significantly higher in tissue than the control group, but showed no difference in plasma. The testosterone level of the vitamin E supplemented group was significantly greater in both tissue and plasma compared to the control.
The human part of the study consisted of only eleven healthy men. Their ages ranged from 30 to 69, with the average being 54 years of age. They were treated to a daily dose of 483 mg of vitamin E acetate and their blood was drawn for analysis after 2, 4, and 8 weeks of treatment. After two weeks of supplementation, the subject’s plasma levels of vitamin E hit a peak. After eight weeks of supplementation, the subjects had an average increase of 30% in total testosterone and 28% in free testosterone. The men’s LH was not statistically changed during the study.
Here’s the most interesting part of the human study. The researchers hit the subjects with a dose of human chorionic gonadotropin (HCG) both before and after the eight week vitamin E trial. HCG is a drug that mimics the action of luteinizing hormone (LH). Prior to the vitamin E, the HCG caused a 47% rise in the men’s testosterone. After the eight weeks of vitamin E, the HCG caused an 84% spike in the men’s testosterone. Moreover, the rate of increase in testosterone as a response to HCG was greater after the 8-week vitamin E treatment.
A legitimate criticism of the human portion of this study is that there was no control group.
Vitamin E and Testosterone: Negative (sort of) Study
If someone mentions that vitamin E can lower testosterone, they’re probably citing a long-term study published in The Prostate back in 2001. In a nutshell, this study extracted a sample of 200 men from a bigger study called the Alpha-Tocopherol Beta-Carotene Cancer Prevention (ATBC) study. The researchers hypothesized that statistically lower incidents of prostate cancer among tocopherol supplemented men in the bigger study might have been due to reduced androgens.
They took 200 men from the bigger study, 100 of whom were supplemented with dl-alpha tochopheryl acetate and 100 of whom received a placebo over a period averaging 3.7 years. The participants were matched on age, study center, and length of time between blood draws among test and control subjects. A dosage of 50 mg. per day of a-tocopherol (small dosage, btw) had been taken by the test participants during the time-frame with at least 90% of capsules consumed.
The results showed an average total testosterone level of (get ready for this) 557 ng/dl in the a-tocopherol group and 579 ng/dl in the placebo group. That’s a whopping… 6% difference. But it’s enough to be statistically relevant. This was after blood work showed 38% higher a-tocopherol levels in the study group versus the placebo. There were also small differences in other hormones between the two groups, among them prolactin and androstenedione.
Of note: There was a 20% lower level of sex hormone binding globulin SHBG among the a-tocopherol group compared to placebo. SHBG is the glycoprotein that binds androgens, inversely determining the level of free testosterone in the blood. Although this resulted in the level of free testosterone in the a-tocopherol group being minimally higher than the control, it’s interesting that free-T increased despite total-T being down (a whopping 6%).
Based on these numbers, researchers of the study concluded that long-term tocopherol supplementation decreases serum androgen levels. They then hypothesized that this is the reason it reduces the incidence and mortality rates of prostate cancer.
Vitamin E and Testosterone: Balance is the Key
It’s obvious we have limited and flawed studies as our only available citations in the question of whether vitamin E supplementation positively affects testosterone. The first study was short-term with a small human sample and no control group. The second was longitudinal, but used relatively small doses of one form of vitamin E (in isolation), incidentally, among a couple hundred non-exercising smokers.
Then there are probable imbalances. Long-term supplementation with alpha-tocopherol in absence of the other tocopherols (especially gamma-tocopherol) has demonstrated negative effects. We need the gamma version along with the alpha version for long-term benefits from vitamin E.
In addition, supplemental a-tocopherol appears antagonistic to and depleting of vitamin K. We already know that adequate vitamin K2 is important for high testosterone.
Vitamin E and Testosterone: Just an Idea
Based on the first study, here’s just an idea that entered my mind. It’s for men diagnosed with low testosterone who might too-hastily accept a doctor’s recommendation to go on testosterone replacement therapy (TRT).
What if such a guy said, “Hey Doc, how about you prescribe me a few shots of HCG after I get my act together within a few weeks or months?”
Once he gets a doc’s approval on everything, he cleans up his diet, starts exercising, gets rid of excess body fat, makes sure other vitamins (K and D) are up, and takes at least eight week’s worth of a balanced vitamin E supplement (balanced tocopherols).
With blood vitamin E levels up, he gets a few monitored HCG shots to bring up his natural T. Then, remaining healthy and on reasonable levels of vitamin E, he and the doctor see where his hormone levels settle out after the short HCG therapy.
Just an idea; nothing more.
- Fumio Umeda, Ken-Ichi Kato, Kazuo Muta, Hiroshi Ibayashi. ‘Effect of Vitamin E on Function of Pituitary-Gonadal Axis in Male Rats and Human Subjects’ Endocrinologia Japonica (Vol. 29, No. 3, P 287-292)
- Terryl J. Hartman, Joanne F. Dorgan, Karen Woodson, Jarmo Virtamo, Joseph A. Tangrea, Olli P. Heinonen, Philip R. Taylor, Michael J. Barrett, Demetrius Albanes ‘Effects of long-term α-tocopherol supplementation on serum hormones in older men.’ The Prostate (Volume 46, Issue 1, Pgs 33–38) Jan 2001
- Dr. Ray Peat. ‘Vitamin E: Estrogen antagonist, energy promoter, and anti-inflammatory.’ Raypeat.com/articles
- Sarah L Booth, Ines Golly, Jennifer M Sacheck, Ronenn Roubenoff, Gerard E Dallal, Koichiro Hamada, Jeffrey B Blumberg. ‘Effect of vitamin E supplementation on vitamin K status in adults with normal coagulation status.’ The American Journal of Clinical Nutrition (Vol. 80, No.1, Pgs 143-148) July 2004
- Han-Yao Huang, Lawrence J. Appel. ‘Supplementation of Diets with α-Tocopherol Reduces Serum Concentrations of γ- and δ-Tocopherol in Humans.’ The Journal of Nutrition (Vol. 133, No. 10 3137-3140) Oct. 2003