Otherwise known in scientific circles as Pausinystalia yohimbe, this tall evergreen tree that grows naturally in western Africa has been used for centuries to increase male sexual performance and sex drive. In more recent years, scientists have discovered that yohimbe bark is a concentrated source of a bioactive compound called yohimbine, which is responsible for most of yohimbe’s actions in the body. Today you can find yohimbe bark, yohimbe extract (standardized for yohimbine alkaloids), and pure yohimbine HCL in supplements formulated to increase sexual performance and promote fat burning. If you are interested in trying a yohimbe or yohimbine based supplement out, then read on to find out how this stuff works and what it can do for you.
Prior to the introduction of drugs like Viagra, yohimbine was commonly prescribed to treat erectile dysfunction. Yohimbine is a potent and specific alpha-2-adrenoreceptor (A2R) blocker. A2Rs are located throughout the body and are commonly found in blood vessels that provide blood flow to the penis for achieving erection. When A2Rs are activated by adrenaline (aka epinephrine) or noradrenaline (aka norepinephrine) then blood vessels become constricted and blood flow to the penis is limited— a condition that promotes erectile difficulty. Interestingly, your body’s adrenaline and noradrenaline levels become elevated with stress, increasing age, and when you become overweight. So it stands to reason why erectile dysfunction gets worse when we are stressed out, get older, and/or become out of shape. This is where yohimbine can come to the rescue, as it effectively blocks noradrenaline and adrenaline from binding to A2R’s in penile blood vessels, thereby promoting widening of the blood vessels and increased blood flow to the penis. All in all, yohimbine is a pretty effective treatment for mild erectile problems, especially those caused from short-term psychological stress.
Beyond increasing the quality of erections, yohimbine has been shown to increase sexual arousal in men and women. This aphrodisiac effect is caused by a few known mechanisms. First, in the brain, yohimbine blocks pre-junctional A2Rs on nerves that spit out noradrenaline. Normally, pre-junctional A2Rs limit the amount of norepinephrine that is released from these nerves (kind of like applying the brakes). However, when you take yohimbine and block A2Rs, the brakes are released and the nerves spit out more noradrenaline into the brain—leading to a feeling of arousal. Second, in the body, yohimbine boosts sex drive by increasing blood flow to sexual organs and heightening nerve excitability in the nerves that control the sensitivity of the genitals.
A placebo controlled study carried out several years ago in Germany and published in the International Journal of Impotence Research showed that, compared to those who received a placebo, subjects who took yohimbine had greater overall improvement in sexual desire, sexual satisfaction, frequency of sexual contacts, and quality of erection (penile rigidity) during sexual contact/intercourse. Notably, due to the high amount of variability in responses among subjects, the results from studies investigating the role of yohimbine on sexual performance should be interpreted with caution. Simply put, yohimbine works great for many, okay for others, and not so great for some. [JORDANA: you can leave this red section out if you like….. I was just making sure I didn’t overstate the research]
In terms of fat burning, yohimbine acts through increasing the release of fats from fat cells (adipocytes) into the blood stream, which are then used for energy. This occurs by at least 3 mechanisms. First, yohimbine blocks A2Rs that reside on fat cells which (when activated) limit the amount of fat that’s allowed to be released—hence blocking them removes this limitation and allows fat to move freely out of the adipocytes and into the blood stream for increased fat burning. Second, the nerves that reside along with fat cells release noradrenaline, which binds to beta-receptors (B2Rs) on fat cells, causing them to release fat into the blood stream. Normally, pre-junctional A2Rs located on these nerves limit the amount of noradrenaline that is released (kind of like applying the brakes). However, yohimbine blocks A2Rs and the brakes are released, causing the nerves spit out more noradrenaline and increase fat release into the blood stream. Finally, yohimbine is a mild monoamine oxidase inhibitor (MAOI) (especially at higher doses). Monoamine oxidases are enzymes that breakdown and inactivate noradrenaline. As such, yohimbine (being an MAOI) blocks these enzymes, causing more noradrenaline to hangout around fat cells. This results in increased B2R activation and increased fat release.
Although there have been many scientific and anecdotal reports of yohimbine’s fat burning potential in individuals with higher body fat levels, yohimbine supplementation has been shown to decrease body fat levels even in lean professional athletes. In a study published in Research in Sports Medicine, lean professional soccer players either took 10 mg of yohimbine twice daily (20 mg per day total) or a placebo. In just 3 weeks, those who took yohimbine saw their fat mass go from an already very lean 9.3% down to 7.1%, where the placebo group had no change.
Remember that although yohimbe and yohimbine work similarly, their dosing is very different (due to differences in purity). With yohimbine HCL supplements we recommend 5 to 20 mg per dose, 2 to 3 times per day between meals. For yohimbe supplements we recommend 500-2000 mg per dose, 2 to 3 times per day between meals. If you are supplementing for fat burning, then one of your doses should be taken 20-30 minutes before training. Remember to always start with the lowest dose to test your tolerance. As well, if you are using yohimbe, there may be notable differences in purity from product to product (noted on label as % standardization for yohimbine)—-make sure to adjust doses upward or downward accordingly.
Yohimbe and Yohimbine supplements are not for everyone, as tolerance varies from individual to individual. The side effects associated with yohimbe or yohimbine supplementation are related to increased levels of adrenaline and noradrenaline in the brain and body. As such, those who are sensitive or take large doses may have increased blood pressure and heart rate as well as headaches, dizziness, anxiety, nausea and sleeplessness. If you are being treated for high blood pressure, heart disease or kidney disease or taking any other prescriptions you should consult with your doctor before taking yohimbe or yohimbine.