To build muscle, you have got to be in an anabolic state. That means that you need to have a lot of testosterone floating around your system. This male hormone helps to build lean muscle tissue, decreases body fat and cellulite and boosts mental sharpness. Even though your body produces testosterone, that level drops dramatically after the age of 25 (Edit: However, a study claims age alone doesn't cause a drop). To continue building muscle after that age, you need to boost your body's natural “T” levels.
There are a number of products on the market designed to boost testosterone levels naturally. One product which has been gaining popularity is Nugenix. So, how scientifically sound is this natural testosterone booster? Let's take a look.
Nugenix is an all natural testosterone booster. Nugenix has been heavily hyped on the internet and has a lot of positive reviews online. Nugenix is manufactured and marketed by the same company that puts out Instaflex and Lumiday. It consists of a combination of zinc, vitamins 6 and B12, along with a special testosterone booster complex. The Nugenix range of products has grown to five items – Nugenix Prostate Health Support, Nugenix PM-ZMA, Nugenix Ultimate, Nugenix Esto-Regulator and Free Testosterone Booster. In this review we focus on their Free Testotserone Booster.
Vitamin B6 is essential for general health. It promotes protein and carbohydrate metabolism and aids in the release of energy. It also assists in proper nerve functioning and the synthesis of red blood cells. B6 occurs naturally in such high protein foods as meat, poultry and fish.
Research shows that Vitamin B6 plays a key role in the regulating of healthy testosterone levels. B6 cannot be produced naturally by the body but must be obtained from diet and supplementation. It does, however, boost the body's natural production of androgen. These, in turn, cause testosterone levels to increase. At the same time, Vitamin B6 regulates the release of such hormones as estrogen, which have a detrimental effect on testosterone (1, 2).
Vitamin B12 is needed to make red blood cells, DNA, RNA, and myelin for nerve fibers. It boosts the capacity to carry oxygen through the body, and boosts the immune system. Vitamin B12 is commonly called Cobalamin.
A 1984 study conducted by Isoyama, Kawai, et al. looked at the effect of supplementing with Vitamin B12 to increase sperm count. 26 infertile men were given 1500 ug of B12 for between four and 24 days. Although total sperm count increased in 14 cases, the testosterone levels for all 24 men remained unchanged (3). This research suggests that Vitamin B12 is not an effective booster of testosterone.
Zinc is an important mineral that assists muscle growth, boosts testosterone levels and helps to develop mental sharpness. Zinc levels in the body concentrate in the testes, acting a key building block of testosterone. It also has a diminishing effect on the testosterone blocking hormone, prolactin.
Studies have shown that zinc supplementation for just six weeks can boost testosterone levels (4). Because you lose zinc when you sweat, it is important to be constantly replacing it, especially when you are regularly working out.
Citrulline malate is an amino acid that can provide extra training endurance. It also increases blood flow to bring on the pump effect while working out with weights. The body converts citrulline to nitric oxide,which has the effect of dilating the blood vessels to allow more blood and nutrients to flow to the working muscle cell (5).
Supplementing with citrulline malate will also reduce post exercise muscle soreness.
Testofen is a registered compound that is primarily made up of fenugreek root extract. It is a common ingredient in testosterone boosting supplements. Fenugreek is a tropical African plant. It is claimed to be able to boost the libido and increase nitric oxide levels in the body. It is also claimed that the high saponin content increases testosterone levels. However, the only studies that have been done have been in-house studies commissioned by supplement manufacturers. Due to the lack of independence of such studies, they cannot be relied upon.
Tribulus Terrestris is a popular herbal supplement among the bodybuilding community. Deriving from Bulgaria, it was first brought to market under the name Tribestan. In it's native country it has been used for centuries as a treatment for infertility and impotency. In the U.S., however, it has been marketed as a testosterone booster.
It is believed that tribulus terrestris increases testosterone levels by increasing the body's levels of a pituitary hormone called ‘lutenizimg hormone (LH). LH regulates testosterone levels in the body.It is also thought that increasing LH levels actually turns on the body's natural production of testosterone.
In the absence of independent studies, however, it is not possible to definitively claim that Tribulus Terrestis will boost testosterone levels.
Nugenix includes a number of ingredients, which are listed and explained on the official website. While a couple of these ingredients, such as zinc and Vitamin B6, have been shown to be beneficial as boosters of the body's natural production of testosterone, the remainder of the ingredients either have no clinical support or have only been shown to be beneficial as testosterone boosters by studies that were sponsored by the supplement companies themselves. As a result, we believe that such ingredients as citrulline malate and Vitamin B12, while having other beneficial health effects, will only have a placebo effect as a Testosterone booster. The effects of zinc, B6 and, possibly, Tribulus Terrestris, will have a positive effect on “T” levels.
While doing nothing to enhance testosterone levels, the ingredients that have been shown to increase nitric oxide levels and blood flow will help to overcome erectile dysfunction problems.
All of the ingredients contained in Nugenix are completely natural and safe, with no known side effects. However, quite a few online reviews do mention adverse side effects. These include stomach upset, bloating, wheezing, swelling and diarrhea.
Because the ingredients are included as a proprietary blend, we do not know how much of each ingredients are included in the product. We cannot tell, then, if the levels are sufficient to provide an effective dosage.
Nugenix is an award winning product that claims to increase testosterone levels for muscle building as well as enhancing sexual functioning. It comes with a 14-day free sample. The cost of Nugenix, however, is high, with a 30 capsule bottle costing $69.99 ($2.33 per capsule). With a serving size of 3 capsules, that will give you just a 10-day supply.
There is no scientific proof offered on the Nugenix website that this product will increase testosterone levels. It doesn't contain any unique ingredients. Those that are in it can be found in other, less expensive products.
(1) Bliskind and Bliskind (1942); Inactivation of Testosterone Propitianate in the liver during Vitamin B Complex deficiency, alteration of estrogen-androgen equilibrium. http://press.endocrine.org/doi/abs/10.1210/endo-31-1-109
(2) Symes EK, Bender DA, Bowden JF, Coulson WF.; Increased target tissue uptake of, and sensitivity to, testosterone in the vitamin B6 deficient rat https://www.ncbi.nlm.nih.gov/pubmed/6727359
(3) Isoyama R, Kawai S, Shimizu Y, Harada H, Takihara H, Baba Y, Sakatoku J.: Clinical experience with methylcobalamin (CH3-B12) for male infertility https://www.ncbi.nlm.nih.gov/pubmed/6485962
(4) Netter A, Hartoma R, Nahoul K.: Effect of zinc administration on plasma testosterone, dihydrotestosterone, and sperm count. https://www.ncbi.nlm.nih.gov/pubmed/7271365
(5) Pérez-Guisado J1, Jakeman PM.: Citrulline malate enhances athletic anaerobic performance and relieves muscle soreness. http://www.supplementreviewsau.com/amino-acid/scivation-xtend-review/
Steve Theunissen is a freelance writer living in Melbourne, Australia. He is a former gym owner and personal trainer and is the author of six hardcopy books and more than a hundred ebooks on the topics of bodybuilding, fitness and fat loss. Steve also writes history books with a focus on the history of warfare. He is married and has two daughters.