Steel Libido from Irwin Naturals is a sexual enhancer that aims to help improve performance and sexual desire. According to statements made by Irwin Naturals, Steel Libido's sexual enhancing mechanisms include:
Support of the blood vessel system involved in male organs
Targeted nutraceuticals that the body uses to generate sexual desire and drive.
Traditional botanicals to promote sexual energy
Steel Libido contains Bioperine, which enhances the bioavailability of the active ingredients, meaning that they are better absorbed by the body, and should therefore enhance their effects. Steel Libido has 2 formulations - a Steel Libido for men, and a Steel Libido for women, with minor differences in the ingredients. One major difference between the men and women versions is that each serving for men is 4 liquid gels, and only 2 liquid gels for the women formula. The main common ingredients in both Steel Libido formulas are Maca powder, Ashwagandha powder, tribulus extract, and horny goat weed. Below, we'll take a look at some of these ingredients.
As mentioned earlier, the two formulas have much in common, sharing a list of common ingredients: Maca powder, Ashwagandha powder, tribulus extract, and horny goat weed. Let's review these ingredients in a little detail below.
Maca powder - Lepidium meyenii or maca is an herbaceous plant that is native to the high Andes of Bolivia and Peru. Maca is a cultivated root belonging to the brassica family used in the Andean region for its supposed aphrodisiac properties. [1] There have been numerous studies performed on human subjects demonstrating the positive effects Maca has on sexual well-being and improvement in perceived sexual performance. Below we have 3 studies confirming the various benefits Maca has relating to sexual well-being.
Subjective effects of Lepidium meyenii (Maca) extract on well-being and sexual performances in patients with mild erectile dysfunction: a randomised, double-blind clinical trial. Zenico T, Cicero AF, Valmorri L, Mercuriali M, Bercovich E.
Department of Urology, Morgagni-Pierantoni Hospital, Forlì, Italy. t.zenico@ausl.fo.it
50 Caucasian men affected by mild erectile dysfunction (ED) participated in this double blind, randomised clinical trial. The men were treated with a Maca extract of 2400mg or a placebo, and the effect of the Maca treatment was tested using the International Index of Erectile Function (IIEF-5) before and after 12 weeks of treatment.
After 12 weeks of treatment, both Maca- and placebo-treated patients experienced a significant increase in IIEF-5 scores. However, patients taking Maca experienced a more significant increase than those taking placebo (1.6 +/- 1.1 versus 0.5 +/- 0.6, P < 0.001), which is significant. Both Maca- and placebo-treated subjects also experienced a significant improvement in psychological performance-related SAT-P score, but the Maca group higher than that of placebo group (+9 +/- 6 versus +6 +/- 5, P < 0.05).
Based on the data collected from the trial, they concluded that supplementing Maca had a significant effect on the subjective perception of general and sexual well being. [1]
Lepidium meyenii (Maca) improved semen parameters in adult men. Gonzales GF, Cordova A, Gonzales C, Chung A, Vega K, Villena A.
Department of Physiological Sciences, Faculty of Sciences and Philosophy and Instituto de Investigaciones de la Altura, Universidad Peruana Cayetano Heredia, Lima, Peru. iiad@upch.edu.pe
This study was designed to determine the effect of a 4-month oral treatment with tablets of Lepidium meyenii (Maca) on seminal analysis in nine adult normal men aged 24-44 years old. The 9 men received either 1500mg or 3000mg of Maca tablets each day for 4 months, and seminal analysis was performed according to guidelines of the World Health Organization (WHO). After 4 months of treatment, the study found that treatment with Maca resulted in increased seminal volume, sperm count per ejaculum, motile sperm count, and sperm motility. It was concluded that Maca improved sperm production and sperm motility.
Effect of Lepidium meyenii (MACA) on sexual desire and its absent relationship with serum testosterone levels in adult healthy men. Gonzales GF, Córdova A, Vega K, Chung A, Villena A, Góñez C, Castillo S.
Instituto de Investigaciones de la Altura, Universidad Peruana Cayetano Heredia, Lima, Peru. iiad@upch.edu.pe
This was a 12 week double blind placebo controlled, randomized, parallel trial to study the effect of Maca treatment on subjective report of sexual desire. Men aged 21-56 years received Maca in one of two doses: 1,500 mg or 3,000 mg or placebo. Self-perception on sexual desire, score for Hamilton test for depression, and Hamilton test for anxiety were measured at 4, 8 and 12 weeks of treatment.
After 8 weeks of treatment, an improvement in sexual desire was observed in the Maca treated subjects. The study also found that Maca did not affect serum testosterone and oestradiol levels. They concluded that treatment with Maca improved sexual desire.
From these studies, the benefits of Maca for improved sexual function is clear. We'll briefly summarize the many demonstrated sexual benefits of using Maca below:
improved sexual psychological performance
better erectile function
improved perception of sexual performance and well being
increase in sperm count and sperm production
better motility in sperm
increase sexual desire
No side effects of any sort was mentioned in any of these studies. One thing to note, however, is the relatively large doses of Maca administered to the participants in all 3 studies. The Maca dosages were either 1500mg or 3000mg, while the Maca content contained in Steel Libido for men is 260mg and 132mg for the women formula. Compared to the much larger doses used in the clinical trials, it brings into question whether the much smaller doses in Steel Libido would allow the user to experience similar levels of benefits.
Tribulus Extract - Tribulus Terrestris is a natural herb used for its
medicinal effects around the world. Tribulus is extracted
from the plant, and used as a natural nutritional supplement.
It has been used for centuries by the Chinese to calm the
liver, treat headaches, dizziness, and premature ejaculation. Apart from its claims for improvement of sexual functions in men, the puncturevine plant (Tribulus terrestris: TT) has long been considered as an energizer and vitalizer in the indigenous system of medicine. [4]
Tribulus terrestris is a common ingredient used in various testosterone and sexual enhancer such as BSN Axis HT, Nutrex Vitrix, Palo Alto Paravol, Steel Libido, among other supplements. If you're searching for testosterone and sexual enhancers, clicking the links above will take you to the reviews for those products.
There are plenty of research performed on animals showing the sexual benefits of consuming tribulus. While there are studies conducted on tribulus studying its effects on athletic performance using human subjects, there are none conducted on the sexual enhancing effects of Tribulus on human subjects - at least none that I was able to find. However, there are plenty of studies done using lab animals mostly using rats and rabbits. Below is one such study:
Sexual effects of puncturevine (Tribulus terrestris) extract (protodioscin): an evaluation using a rat model. Gauthaman K, Ganesan AP, Prasad RN.
Department of Obstetrics and Gynaecology, National University Hospital, National University of Singapore, Singapore.
40 male rats were randomly divided into 4 groups of 10 each. Group 1 was the control group, and the remaining 3 groups were treated with different doses of tribulus (2.5, 5, and 10mg/kg) for 8 weeks. After the 8 weeks, for group 2-4 rats the intracavernous pressure (penile erection) increased significantly (43% and 26% for groups 3 and 4 respectively). Sexual intercourse frequency increased by 27% and 24% for groups 3 and 4. Other improvements in sexual behaviour was also observed. The study concluded that the increase in intracavernous pressure confirms the proerectile aphrodisiac property of tribulus could possibly be the result of an increase in androgen and subsequent release of nitric oxide.[4]
While I could not find any studies conducted using human subjects, there exists plenty of anecdotal evidence that Tribulus Terrestris helps improve sexual functions and increases libido. It is a widely used ingredient in many testosterone and sexual enhancers as mentioned above.
1. Andrologia. 2009 Apr;41(2):95-9.
Subjective effects of Lepidium meyenii (Maca) extract on well-being and sexual performances in patients with mild erectile dysfunction: a randomised, double-blind clinical trial.
Zenico T, Cicero AF, Valmorri L, Mercuriali M, Bercovich E.
Department of Urology, Morgagni-Pierantoni Hospital, Forlì, Italy. t.zenico@ausl.fo.it
2 Asian J Androl. 2001 Dec;3(4):301-3.
Lepidium meyenii (Maca) improved semen parameters in adult men.
Gonzales GF, Cordova A, Gonzales C, Chung A, Vega K, Villena A.
Department of Physiological Sciences, Faculty of Sciences and Philosophy and Instituto de Investigaciones de la Altura, Universidad Peruana Cayetano Heredia, Lima, Peru. iiad@upch.edu.pe
3. Andrologia. 2002 Dec;34(6):367-72.
Effect of Lepidium meyenii (MACA) on sexual desire and its absent relationship with serum testosterone levels in adult healthy men.
Gonzales GF, Córdova A, Vega K, Chung A, Villena A, Góñez C, Castillo S.
Instituto de Investigaciones de la Altura, Universidad Peruana Cayetano Heredia, Lima, Peru. iiad@upch.edu.pe
4. J Altern Complement Med. 2003 Apr;9(2):257-65
Sexual effects of puncturevine (Tribulus terrestris) extract (protodioscin): an evaluation using a rat model.
Gauthaman K, Ganesan AP, Prasad RN.
Department of Obstetrics and Gynaecology, National University Hospital, National University of Singapore, Singapore.
