T Nation

Tribulus and Gyno


Interesting read. Has to be taken in context, ie, it is only a case study and the bloke could have been lying etc etc.

However, at face value, it appears like lots of things people with pre-existing conditions may be susceptible to side effects from supplements.

PS I have never attached a PDF file before - not sure if it will work!

[Moderator Note: You cannot attach a .pdf file, only images. You can, however, cut & paste text into a post on the forum.]


Any other way to get the article? I'm very interested, and even more sceptical.


3rd Time lucky!

The Breast (2004) 13, 428?430

Gynaecomastia and the plant product ??Tribulis terrestris??

J.K.A. Jameel, P.J. Kneeshaw, V.S.R. Rao, P.J. Drew*
Academic Surgical Unit, Castle Hill Hospital, University of Hull, Cottingham, East Yorkshire HU16 5JQ, UK

Summary Gynaecomastia is the commonest benign breast condition seen in men. It is well recognised that certain drugs that alter the normal sex hormonal profile in the body can induce gynaecomastia. Recently, an increasing use of androgenic-anabolic steroids among young men especially body-builders has increased the incidence of gynaecomastia. We report a case of a young weight-trainer who developed gynaecomastia due to oral intake of a herbal tablet which he used as a steroid alternative for body-building.

Case report
A 21-year-old gentleman who works as an aircraft fitter and is also a keen weight-trainer was referred by his general practitioner to the breast clinic with a 5 month history of a lump in his left breast which was occasionally painful. Seven years previously, he reported a similar swelling on the right side that had settled spontaneously. He was otherwise fit and well. He smoked 2 cigarettes a day and drank about 10 units of alcohol a week.

On examination there was a well-defined nodule in the sub-areolar region on the left side consistent with gynaecomastia. This was causing him considerable discomfort especially while playing sports and he requested surgical removal. In view of the patient?s symptoms and wishes, this was excised using a minimally invasive technique (mammotome probe and liposuction).6 Two weeks later at clinic follow-up, his wound had completely healed and he was very pleased with the cosmetic result. The histology was reported as atypical ductal hyperplasia (ADH), therefore he was not discharged but kept under surveillance.

When reviewed in the clinic 3 months later, he presented with another nodule again in the left sub-areolar region. On clinical evaluation and ultrasound imaging this nodule appeared benign. Core-biopsy was reported as normal breast tissue with a possibility of gynaecomastia difficult to exclude. A complete sex hormonal profile was requested. This revealed a markedly decreased follicle-stimulating hormone (FSH), leutinising hormone (LH) and testosterone. FSH 0.59 IU/l (normal: 1.0?7.0), LH 0.26 IU/l (normal: 1.0?8.0), testosterone 1.3 nmol/l (normal: 10?50). Prolactin, oestradiol and progesterone were within normal limits.

On closer questioning at this stage, the patient said that he had been taking a non-hormonal preparation derived from a plant called Tribulis terrestris, in the form of tablets as a steroid alternative to supplement his weight-training. On the assumption that this substance had caused the hormonal imbalance and hence gynaecomastia, he was advised to discontinue taking them. Two months later his sex-hormones were re-checked and they had improved, FSH 11 IU/l, LH 6.1 IU/l, testosterone 15 nmol/l. The swelling in his left breast had also completely resolved.

Gynaecomastia usually presents as a unilateral tender enlargement of the sub-areolar breast tissue. It can be physiological as in neonatal, pubertal and senescent hypertrophy. It can also be associated with specific diseases and intake of certain drugs.7 In any case, the hormonal change that mediates the condition is a decrease in androgens that can be due to either reduced production or androgen resistance. Increased circulating oestrogens that can be due to increased peripheral aromatisation may also decrease androgen expression. Androgenic-anabolic steroids (AAS) are the most widely misused group of drugs in competitive sport.8 They increase strength, lean body mass improving the athlete?s appearance and performance.9

AAS have many side-effects of which acne, striae and gynaecomastia were the most commonly reported in one study on 100 athletes.10 Hence, an increasing number of young men have turned towards steroid alternatives which could provide the benefits of AAS with minimal side-effects.

One such is the tablet taken by our patient, the active components of which are steroidal saponins of furostanol type isolated from ??above the ground?? part of the plant ??T. terrestris L. bulgaricum??. It is regarded as a natural herbal alternative to AAS. Its mechanism of action is not fully clear. It is believed to have a central effect and increase secretion of LH and therefore increase testosterone levels. Alternatively, it may exert its effect by being metabolised into androgen-like products or stimulating the physiological transformation of testosterone into more active dihydrotestosterone. 11,12 In our patient both gonadotropins and testosterone were markedly reduced after taking this preparation in contrast to experimental studies on this product which showed enhancement of LH and testosterone.12 In the absence of signs or symptoms of pituitary insufficiency, in an otherwise healthy individual, we believe that this could either be due to the shut-down of the pituitary gonadal axis in the presence of exogenous substances or due to increased aromatisation and peripheral conversion into estrogens, both of which could contribute to development of gynaecomastia. Furthermore the histology of the excised tissue revealed ADH. Although the pathologic interpretation is subject to interobserver variability, it is well recognised that ADH falls on a pathologic continuum between benign hyperplasia and ductal carcinoma and it is associated with a 4-fold to 5-fold increased risk of breast carcinoma.13 In our patient the abnormal tissue was completely excised and a subsequent core-biopsy did not show any ductal hyperplasia or atypia, however the development of ADH, a precancerous condition raises concern on the safety of this plant preparation.

In summary, this preparation which is believed to be a natural product with minimal side-effects should be regarded as a possible gynaecomastia inducing agent through its effect on sex hormonal levels in the body. Its link in the development of ADH may also suggest a possible carcinogenic effect on the breast tissue, although more definite evidence on these aspects needs to be established. It is important for clinicians to keep an open mind while eliciting drug history and not discard the natural products which many patients take but fail to disclose, as this could play a major part in the pathogenesis and with appropriate timely intervention cure of the disease.


I remember seeing this a while back.

I'd say whatever this man was taking, it had to contain some sort of potent, exogenous androgen. Whether he realized it or not is another story.

He's clearly hypogonadal when he's taking the product in question. LH and testosterone are both well in to the subphysiological range. As the authors even note, that is the exact opposite of what has been published when subjects are administered tribulus.

I know of a great deal of individuals who have simply lied to their physicians and told them they were taking a dietary supplement for fear of having to admit that they were taking an illegal substance.

The other explanation could be that he was taking a product which had certain androgens in it.

It would have been much more helpful if they had requested that he bring the supplement in for at least, if nothing else, a visual inspection of the ingredients.


Good points Cy, I was wondering this myself - and why the reviewers didn't at least ask to have further testing on the product used. Otherwise their are too many unknowns - ie he was lying or taking something other than what he thought he was taking. Medical journals appear pretty lax on strong science particularly on these case study type of incidents.

The fact that he previously had gyno at the age of 14 would make you think (hopefully) that he hadn't/wasn't taking AAS. Although Dr House (from HOUSE MD) is adamant that patients always lie!!!


Hi Swerven,

Yes, although I'm not saying this is absolutely the case here, I unfortunately know a great deal of people asking for excuses to give to their physicians when encountering adverse effects from androgen use, due to fear of admitting to illegal drug use. Anywhere from explaining any elevated liver enzymes, to undetectable HDL, as well as abscesses and yes, even gynecomastia. I think that also obviously can create a major problem for physicians trying to treat these patients when their patients aren't being honest with them.


A) this is a case study so it could just be some really statistically abnormal phenomenon, or just a really abnormal dude. I never trust case studies, they're worth less than the paper they're written on.

B) the subject's tribulus supplementation was only discovered on further questioning following a recurrance. I think he was probably holding something back (like he was taking something more than tribulus) or lying - I mean it was something that he was willing to not mention even at the prospect of having surgery.

A) could (I sincerely doubt) have been more than tribulus in whatever he bought, but it would have to be prety strong (and thus likely more expensive to produce)


Correct me if Im wrong but isnt it not that uncommon for young teenagers to get gyno?


i've had slight gyno since i was 14... i was told to wait into my 20s and it might subside on its own... no such luck though


How many TRIBEX users have sprouted breasts? I think it's clear that if Tribulous was the culprit here there would be many reports throughout different boards on the net of said side effects.


Gday Insane,
Out of interest, you ever taken any supps that have affected the gyno, ie, good or bad effects.


I take TRIBEX and I don't have gyno .. I want to read your article, but like most supplements there is plenty of bs in the air. Take a look at creatine for example, I've read on some sites it makes your dick shrink ...? You make the call


Yeh mate - my old man smokes like a chimney but he doesn't have cancer, great argument. No one here is saying that taking tribulus will give you Gyno. Having said that, no one here for sure can say that in certain individuals it might be a possibility. In the article the authors suggest a possible mechanism - Cy might be able to come up with a few more scenarios. The point is - who really knows.

I personally only take supplements after they have been out for a while and I can gauge the benefits and side effects from reading and research. When I do decide to take something I fully understand that there is always some 'unknown' risk or potential side effect.

The published article (which separates it to some extent from random bs on an internet site) has a number of flaws that were pointed out earlier in the post. I'd suggest that you (and BDog) might want to be a bit more open minded and discerning about where you get your info from. Remember, it was once dogma that earth was flat and the sun revolved around it.



I recently stopped taking a tribulus supplement (20,000mg a tablet I think) because it made my balls ache and my nips itch. I have used other weaker products previously without any problems. Obviously this could be related to something else, but I stopped and restarted twice and the same thing happened. I'm not using AAS, so it has nothing to do with that.