By John H. Biggs BSc, NCP - Owner Optimum Health Vitamins Share on Facebook
Most people associate testosterone with excessive muscle development and a “Machismo” male air. But testosterone affects countless bodily functions, and adequate levels are actually essential in both men and women. Achieving optimal levels of testosterone can have positive effects on mood, energy, libido, and sense of wellbeing in both sexes, and studies in men have indicated large impacts on improving insulin function, decreasing body fat, and improving muscle mass.  http://care.diabetesjournals.org/content/28/7/1636.full
What many people don’t realize is that all steroid hormones, including the ones most of us are familiar with such as testosterone, estrogen, and progesterone originate from the same source, i.e. cholesterol. (This is why the first question I often ask men who are having erectile dysfunction is if they are on a cholesterol-lowering drug such as Lipitor or Crestor. Very often the answer is “yes”, and being aware that lowering your cholesterol can impact your sex hormone production is an important consideration for making appropriate decisions, based on your individual situation.)
In the “hormone soup” created as the body converts cholesterol into its large array of “downstream” sex/steroid molecules, it can be extremely difficult to accurately predict where hormones introduced directly into the body are ultimately going to end up. For example, testosterone and estrogen are extremely close in structure, yet the effects they produce are certainly miles apart. Testosterone converts into estrogen through the action of an enzyme called “aromatase”. One of the difficulties with directly introducing testosterone into a man’s body is that much of it may simply convert into estrogen. Accordingly, if effective natural strategies exist many of us may prefer instead to encourage their body’s own natural production of hormones using natural means, providing the body the opportunity to use its native set of checks and measures to achieve its own natural balance.
In this regard there are many botanicals and natural substances that can be helpful, and a few have been scientifically validated. But it is important to be clear that in the world of testosterone boosters, hype predominates. There are many claims that are made, but the science backing them up is usually scant, obscure, or non-existent. Also, there is the assumption that if a substance effectively raises a man’s libido, or erectile function, it is because it raised testosterone levels, and this is definitely not necessarily the case.
Yet there are some products, (particularly the one containing the fenugreek extract discussed below), that are backed up by studies, and have also produced marked, and consistent positive feedback from customers.
Regarding anecdotal evidence if a product produces consistent feedback in those who try it, be it good or bad, I think this carries a lot more weight than it is given credit for. It is always good to remember that what gets discovered by science is usually limited to what gets funded, and since naturally occurring substances are not patentable, such studies often don’t happen, (i.e., lack of scientific evidence is doesn’t necessarily mean a natural substance doesn’t work.
Botanicals often used to increase testosterone include such things as fenugreek extracts, Tribulus terrestris, maca, Panax and Siberian ginsengs and other adaptogens that help support adrenal function, and traditionally used and reputed aphrodisiacs such as, horny goat weed, tongkat ali, catauba, avena sativa, and elk antler velvet. Some of these are discussed below.
- Fenugreek extracts – A 2009 double-blind study in the Journal of the International Society of Sports Nutrition, sponsored by Indian drug company, Indus Biotech, showed that a fenugreek extract (Tradename TESTOSURGE), standardized for a glycosidal saponin called “grecunin” significantly raised total testosterone, as well as showing significant increases in free (bioavailable) testosterone, and over 8 weeks, significantly reduced body fat %.  http://www.jissn.com/content/6/S1/P12
The authors of the study also felt that the results implied (but did not prove) that this fenugreek extract acted as an aromatase inhibitor, accounting for the higher levels of total testosterone, and also acted to reduce Sex Hormone Binding Globulin, (the protein that binds testosterone in the bloodstream, yielding it unavailable), resulting in higher free testosterone.
- Tribulus terrestris – Though one Bulgarian study, in the 1970’s indicated Tribulus will increase testosterone by increasing its upstream hormone luteinizing hormone (LH), and some animal studies have indicated that it will heighten libido and sexual activity, overall the science for Tribulus is scant, though a recent 2011 review article in the Journal of Medicinal Plants provides a good overview. Still some people swear by Tribulus (even including some health professionals). http://www.academicjournals.org/jmpr/PDF/pdf2011/18Aug/Akram%20et%20al.pdf
- Maca – Though studies on Maca have failed to show any effects on hormone status, http://joe.endocrinology-journals.org/content/176/1/163.abstract , it still has been demonstrated in human trials to increase libido, (though apparently not by increasing testosterone.) Maca is reputed to be an “overall hormone balancer”, and given the number of people we have had get good results with it for libido in both sexes, menopause, PMS, energy, sleeping better, etc., etc. this is a good example of where years of results speak more loudly than a lack of studies. Still for a surprisingly extensive review see this link at (of all places) Drugs.com http://www.drugs.com/npp/maca.html#ref23 See also: Gonzales GF , Córdova A , Vega K , et al. Effect of Lepidium meyenii (MACA) on sexual desire and its absent relationship with serum testosterone levels in adult healthy men . Andrologia . 2002;34(6):367-372, and Townsend Letter for Doctors and Patients, November, 1998, issue 184.
- Panax Ginseng – Though small amounts of testosterone are produced by the adrenals, and ginseng is well validated, (all be it traditionally), as an adaptogen to support the adrenals and combat stress, it is perhaps best known for its reputed aphrodisiac properties. Yet, its mechanisms of action appear to be more related to production of nitric oxide as part of the sexual response, then to raising testosterone levels. Here again, it is important to realize that boosting libido does not necessarily equate to higher testosterone levels. http://informahealthcare.com/doi/abs/10.3109/01485018208990207
As mentioned already, other strategies that can be helpful in maintaining and optimizing testosterone status include reducing conversion to estrogen by inhibiting or “downregulating” the activity of the aromatase enzyme, and also to reduce Sex Hormone Binding Globulin, (SHBG), the protein which binds testosterone in the blood, yielding it unavailable.
A natural aromatase inhibitor is the bioflavonoid quercetin. (see http://toxsci.oxfordjournals.org/content/82/1/70.full) , and a natural SHBG inhibitor is nettle root. (ref: Schöttner M, Gansser D, Spiteller G. Interaction of lignans with human sex hormone binding globulin (SHBG). " Z Naturforsch [C]". 1997 Nov–Dec;52(11–12):834–43.)
Another natural and helpful step a man can take to optimize testosterone status is to use substances like saw palmetto, which is well validated for reducing the conversion of testosterone to its “darker” cousin called dihydrotestosterone (DHT), implicated in balding and prostate enlargement. Ref: Potency of a novel saw palmetto ethanol extract, SPET-085, for inhibition of 5α-reductase II Advances in Therapy Volume 27, Number 8, 2010, 555-563.
And don’t forget basic lifestyle strategies like getting enough sleep, avoiding excessive amounts of alcohol (particularly beer, because of the estrogen-promoting Hops it contains), and ensuring adequate intake of vitamin D. These can be very helpful and important for maintaining healthy testosterone levels. This 2010 study showed that men with adequate vitamin D levels had significantly higher testosterone levels than those who were deficient. It also showed that called Sex Hormone Binding Globulin, was significantly lower in the vitamin D-sufficient group. http://www.ncbi.nlm.nih.gov/pubmed/20050857.
In conclusion, if your testosterone is low, or you are middle-aged and just simply not feeling very excited about life, chances are excellent you will get some very beneficial mental and physical effects from raising it… but your choices are definitely not limited to hormone replacement.