Bulbine Natalensis as a Libido Enhancer and Testosterone Booster
Bulbine Natalensis, one of roughly 160 species in the Bulbine genus, is a succulent plant primarily found in Southern Africa.   If you were to drill down to the phytochemical level, you'd find saponins, tannins, alkaloids, anthraquinones, and cardiac glycoside. 
A number of studies on rats and pigs found that Bulbine Natalensis stem can affect testosterone, luteinizing hormone (LH), follicle stimulating hormone (FSH) and estrogen levels as well as wound healing, sex drive, white blood cells, testes, kidney, and liver. Some of these effects appear to be positive whereas others are negative.
After reading this article you should have a much better understanding on the recommended dosage, uses, benefits, and side effects
Bulbine Natalensis Recommended Dosage, Benefits, & Side EffectsIn the fitness community, users typically consume Bulbine Natalensis with the goal of increasing testosterone and sex drive. it's important to note that with the exception of one all studies examining the effects of Bulbine Natalensis have been performed on rats rather than humans. In all five rat studies, researchers compared 25, 50, and/or 100mg/kg of the Bulbine Natalensis stem extract per day to the control group.
The first study separated 60 male rats in to 4 groups of 16 and treated them with one of the aforementioned Bulbine Natalensis doses or distilled water for 14 days. All three dosages of Bulbine Natalensis increased testicle size and protein levels in the testes, but only in the 25 and 50mg/kg dosages increased testicular glycogen and cholesterol levels.  In this case it appears that more is not better and in fact, may be less effective than a moderate dose.
This study suggests that 50mg/kg of bodyweight is the ideal dosage for improving anabolic and androgenic activities.Researchers also found 25 and 50mg/kg dosages led to increased testicular and serum testosterone, testicular phosphatase activity, FSH, and LH concentrations every day of the study whereas 100mg/kg led to a pulse response on the 1st and 7th days.  One may conclude that such a high dose of Bulbine Natalensis overwhelms the body and as a result, produces irregular responses.
This study suggests that 50mg/kg of bodyweight is the ideal dosage for improving anabolic and androgenic activities.  Using Body Surface Area Conversion, this translates to roughly an 8mg/kg dosage which calculates to 550mg for a 150lb person, 730mg for a 200lb person, and 900mg for a 250lb person. 
The second study examines the effects of Bulbine Natalensis on the liver and kidney function of rats when administered for 14 consecutive days. While Bulbine Natalensis did not affect total protein, sodium, potassium, chloride, calcium, magnesium, uric acid, and creatinine levels, 50 and 100mg/kg doses of Bulbine Natalensis decreased liver and kidney size. 
Shrinkage of these two organs can lead to a slew of health problems and in serious cases, organ failure. Further examination revealed that Bulbine Natalensis affects the liver more than the kidney, based on the measurement of gamma-glutamyl transferase (GGT), alkaline phosphatase (ALP), alanine aminotransferase (ALT), and alanine aspartate (AST) levels. 
it's important to note that none of these levels increased or decreased to life-threatening values. After the rats died, their livers and kidneys were dissected and examiners found slight distortions in the architecture of the liver lobules and kidney tubules.  These findings suggest Bulbine Natalensis may alter the shape and size of specific organs; it would be interesting to see if these organ deformities reversed after cessation of Bulbine Natalensis consumption.
Researchers concluded with the finding the extract is not completely safe as an oral remedy. As with concentrating and increasing the dose of most compounds, there will come a point where side effects occur; it's up to the user to decide if the benefits outweigh the side effects.
The third study examined the effects of Bulbine Natalensis on male rat mating and fertility over 7 days of administration. After 7 days, in all three groups consuming Bulbine Natalensis, testes weight increased but epididymis, seminal vesicle, and prostate weights remained unchanged.
Furthermore prolactin levels, sperm count, motility, morphology, and viscosity did not change. However, serum testosterone, progesterone, LH, and FSH increased in the 25 and 50mg/kg body weight groups.
Interestingly enough, the 100mg/kg body weight group experienced decreased the serum testosterone and progesterone levels as well as decreased overall sexual activity. Estradiol levels decreased significantly at all three doses. Researchers deemed that 25-50mg/kg/day of Bulbine Natalensis in female rats is safe during the organ-formation period of pregnancy but 100mg/kg may be harmful during this stage. 
Once again, researchers found 25-50mg/kg/day to be the sweet spot; too much Bulbine Natalensis can have a negative effect on hormones and reproductive health.
The fourth study was a 14-day study showing that all three dosages of Bulbine Natalensis increased white blood cell count but did not significantly change the red blood cell count, haemoglobin, packed cell volume, mean corpuscular volume, mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration and red cell distribution width in male Wistar rats.  An increase in white blood cells is typically indicates the human body is fighting an infection.
Bulbine Natalensis didn't affect low-density lipoprotein (LDL) "bad cholesterol" but it did decrease high-density lipoprotein (HDL) "good cholesterol".  Thus, Bulbine Natalensis may not be tolerated well when dosed long-term, especially with regards to cholesterol and white blood cells. However, it's important to note this was a short-term 14-day study performed on male rats rather than humans.
The fifth study examines the effects of Bulbine Natalensis on the sexual behavior of male rats over 7 days. 25-50mg/kg body weight increased mount frequency, intromission frequency, ejaculatory latency, ejaculation frequency, serum testosterone and LH levels. Mount latency, intromission latency and post-ejaculatory interval also significantly decreased after consuming Bulbine Natalensis.
Rats dosed at 100mg/kg body weight experienced the opposite effects on sexual behavior and hormone levels.  Once again, this study confirms more is not always better and 25-50mg/kg body weight maximizes the upsides and minimizes the downsides.
There is one study examining the safety of Bulbine Natalensis in human subjects over 28 days of supplementation. Researchers took 36 apparently healthy men with an average age of 29.4, average weight of 177.2cm, and average weight of 82.2kg. Using a product called ProLensis, researchers dosed the males 325mg of Bulbine Natalensis in the morning and 325mg six hours after the first dose. 
This equates to a daily dosage of about 8mg/kg of bodyweight; significantly lower than the dosages used in rat studies. Researchers found that this dosage of Bulbine Natalensis did not affect 27 of 29 variables such as heart rate, blood pressure, EKG, and various renal, hepatic, and hematological biomarkers.
Bulbine Natalensis increased alkaline phosphatase (ALP) 3% above baseline whereas the placebo group experienced a 3.8% decrease below baseline.  Elevated ALP levels may suggest liver damage or a condition causing increased bone cell activity is developing. 
Subjects consuming Bulbine Natalensis also experienced a 7.8% decrease in creatinine levels whereas the placebo group experienced no change.  Decreased creatinine levels are typically not a red flag but some patients experience decreased creatinine levels when they have muscle-wasting conditions. 
Researchers concluded that Bulbine Natalensis is as safe as the placebo, maltodextrin, and that these variations are not clinically relevant because absolute levels fell within normative clinical limits.  It would be interesting to see the findings based on the previously studied dose of 25-50mg/kg body weight.
Other Uses of Bulbine NatalensisTopical application of Bulbine Natalensis has long been used in traditional South African medicine as an antimicrobial agent to treat skin wounds and burns.
From the antimicrobial standpoint, researchers isolated three fractions from the Bulbine Natalensis stem and administered each of them to various bacterial species. Of the three fractions (ethanolic extract, n-butanol and ethyl acetate), the ethyl acetate inhibited the growth and spread of 100% of the bacterial species, whereas the other two fractions inhibited 75% and 87.5%, respectively. 
100% versus 87.5% effectiveness in preventing the growth and spread of bacteria may be the difference between life and death due to an infection. Unlike the other two fractions, ethyl acetate prevented the growth of three extremely infamous bacteria strains - Shigelli flexneri, Staphyloccus aureus and Escherichia coli (E. coli).  Antimicrobial compounds are crucial in slowing or preventing the spread of serious and potentially fatal illnesses.
Researchers found that treating the skin wounds on pigs with the leaf gel extract increased the skin's tensile strength (re: breaking point), protein, and DNA content.  Ultimate tensile strength is measured as the force per unit area required to break a material and is reported in megapascals (MPa) or pounds per square inch (lb/in2 or psi). For reference, the ultimate tensile strengths of human skin and nylon are 27.2 +/- 9.3 MPa and 900 MPa, respectively.  
Researchers believe this increased tensile strength is a result of increased fibroplasia rates (the process of forming fibrous tissue), increased collagen deposition and maturation, as well as the differentiation of fibroblasts (the most common type of cell found in connective tissue) in to myofibroblasts (cells involved in the inflammatory response to injury).     A second study on 12 domestic pigs also confirmed Bulbine Natalensis's ability to expedite wound healing, increase collagen, protein, and DNA content within the wounds. 
Based on these findings, topical application of Bulbine Natalensis offers numerous benefits with little or no drawbacks.
Bottom Line on Bulbine Natalensis SupplementsWhile Bulbine Natalensis appears to offer benefits in rat and pig models when consumed orally or applied topically, high dosages and prolonged oral consumption may lead to a number of side effects. If you decide to supplement with Bulbine Natalensis, then you should following the dosing instructions exactly as they're written on the product label.
No supplement is a magic fix-all; if your workout routine, diet, and rest protocols are poorly designed, then progress will be sub-par. However, Bulbine Natalensis could be a great addition to natural testosterone and libido enhancer like MTS Nutrition Barracuda.
MTS Nutrition Barracuda is a 7 ingredient non-proprietary blend designed to naturally increase your testosterone and sex drive. If you have experience with Bulbine Natalensis then let me know in the comments below!
Frequently Asked Questions
Is Bulbine Natalensis safe to stack with other supplements?
Research thus far doesn't advise against or advocate combining Bulbine Natalensis with other supplements. The 28-day double-blind placebo-controlled human trial indicated that 325mg of Bulbine Natalensis twice per day is as safe as the placebo (maltodextrin).  Based on these findings, it appears Bulbine Natalensis-only supplementation is safe for short periods of time, but more research is needed around potential interactions with other supplements.
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