Shaun Ward MSc ANutr
Bulbine natalensis is a herb from the family of Asphodelaceae.
This herb originates in southern regions of Africa and has been traditionally used as an aphrodisiac – a substance that increases sexual drive.
Based on this use in some societies, investigations have taken place to test its effects on hormones that effect sex drive such as testosterone.
The main active compounds in bulbine natalensis include saponins, anthraquinones, tannins, cardiac glycosides, and alkaloids.
The Possible Benefits of Bulbine Natalensis
Below we've listed every potential benefit we've found with credible scientific backing:
Bulbine Natalensis May Increase Testosterone Levels
Increasing testosterone levels may have benefits such as increasing strength levels and sex drive, especially in elderly men who have low testosterone production compared to healthy young males.
Extracts of bulbine natalensis have shown to increase circulating testosterone levels with doses up to 100mg per kg of bodyweight in animal studies. Interestingly, the most effective dose (50mg per kg) is not the highest dose.
It has this effect by stimulating the release of luteinizing hormone from the pituitary gland, however this only occurs after long-term consumption .
Interestingly, the increases in testosterone levels within animals are very dramatic after supplementation, with increases seen up to ~350% compared to placebo .
However, the herbs relationship with testosterone has not been studied in humans and it is very unlikely to have such an extreme effect (otherwise a lot of bodybuilders would be taking it!).
Bulbine Natalensis May Increase Libido
Libido is defined as the energy of sexual drive.
At doses similar to which increase testosterone levels (~50mg/kg), bulbine natalensis also appears to start exerting aphrodisiac (libido-promoting) effects . This is likely a secondary result from the increase in testosterone which is said to be its main function.
Interestingly, these aphrodisiac effects have been reported to be more impactful than Viagra when taken at the same dosage .
However, these findings are only based on limited findings in animal studies, and human clinical trials are necessary to reach a scientific consensus.
It is also important to note that, unlike most other substances that increase testosterone levels, indicators of sperm count and activity seem to remain stable from bulbine natalensis consumption. This could potentially make it a viable alternative to strong medications for libido.
Bulbine Natalensis May Have Antimicrobial Properties
An antimicrobial substance is one that destroys or inhibits the growth of microorganisms (usually pathogenic).
In addition to the bulbine natelensis’ effects on testosterone levels and sex drive, it may also have antimicrobial properties.
This is not surprising as some regions of the world use this product for the management of wounds, burns, rashes, itches, ringworms, and cracked lips.
Current evidence suggests:
- The tannin content possesses the most of the antimicrobial properties via enzyme inhibition and reductions in oxidative phosphorylation .
- The saponin content can exhibit antibacterial activities .
- The specific bacteria which are destroyed are those involved in causing gastroenteritis, food poisoning, and diarrhea .
However, the specific plant fractions in bulbine natelensis that affect different bacterial strains are currently not fully understood .
How To Take Bulbine Natalensis
There is not a great amount of information available to suggest a specific supplementation protocol.
Current recommendations are purely based on dosages that provide the greatest effects on testosterone and sex drive in animal models - and then accounting for body surface area conversions for human use. This correlates to a recommended intake of 8mg per kilogram of bodyweight.
To give examples this means that:
- A 150lb human should supplement with 550mg of bulbine natelensis a day.
- A 200lb human should supplement with 730mg of bulbine natelensis a day.
- A 250lb human should supplement with 900mg of bulbine natelensis a day.
Keep in mind these dosages are only estimates based on a scarce amount of evidence.
Bulbine Natalensis Safety and Side Effects
Despite the reported health benefits, there are some safety issues regarding bulbine natalensis supplementation. These include:
- Raised circulating cholesterol and triglyceride levels that may promote atherosclerosis. In particular, one study found that after just 14 days of consumption, cholesterol levels increased by ~50% and triglycerides by ~100% (seen on day 1 of supplementation). This is hypothesized to be due to increased lipolysis – the breakdown of fats to release fatty acids .
- Toxicology studies have found that the herb might negatively alter liver enzymes and lead to adverse effects such as distortions in the structure of kidney tubules (small structures in the kidney that filter the blood and produce the urine). These adverse effects seem to be dose-dependent .
- Significantly increased white blood cell count that may indicate chronic inflammation .
- Increase in alkaline phosphatase levels which indicates a problem with the liver or gallbladder and is linked to hepatitis, cirrhosis, liver cancer, gallstones, and blockages of bile ducts .
Bulbine natalensis is a herb that originates in southern regions of Africa.
Supplementing with this substance may be able to increase testosterone levels and sex drive, as well as have antimicrobial properties.
However, considering this herb may also increase cholesterol levels and affect the structure of kidney tubules, it is not currently recommended to take this dietary supplement.