Nimbus Healthcare
March 17, 2022 | Testosterone

Alpha Male X Ingredient Focus: Longjack

Written by Dr. Richard Harris

Eurycoma longifolia, also known as tongkat ali or longjack, is a medium-sized shrubby tree found in the jungles of Southeast Asia. Longjack is one of the key ingredients in our Nimbus Alpha Male x testosterone optimization supplement. Why did we include this shrubby plant extract in Alpha Male X?

Longjack contains proteins called eurypeptides which increase the conversion of pregnenolone to DHEA and progesterone to testosterone. 1 - 2 It may also help by increasing the release of testosterone from sex hormone binding globulin (SHBG), the major protein that carries testosterone in the blood. 3 Only free testosterone can interact with cells and cause cellular changes responsible for the effects of testosterone.

Human randomized clinical trials show that extracts of Longjack are effective for increasing blood testosterone levels, among other beneficial effects. A 12-week study of 105 men aged 50 to 70 with a testosterone level of less than 300 ng/dL saw a significant increase in total testosterone, muscle strength, and quality of life. Cortisol levels and fatigue decreased in the longjack group compared to the placebo group. DHEA levels also increased, but the difference was insignificant compared to the placebo. The dosages used in that study were 100 and 200 mg; overall, the 200 mg dose was more effective. 4

Another study in 63 men and women with moderate stress levels found that Longjack at 200 mg daily reduced tension, anger, confusion, and cortisol levels while increasing testosterone compared to placebo. A slight increase in overall well-being was observed, but the difference was insignificant. No adverse effects were seen. 5

Longjack may also increase strength, exercise performance, and recovery. Two clinical trials in young men found that supplementation with 100 mg per day increased lean body mass, one repetition maximum weight, and arm circumference compared to placebo. 6 , 7

Longjack supplementation improved quality of life and sexual libido and reduced abdominal fat mass in overweight and obese participants aged 30 to 55 at a dose of 300 mg per day in a 12-week clinical trial. 8 Individuals trying to lose weight while dieting and athletes undergoing intense training often see a rise in cortisol and a drop in testosterone. Studies have shown that longjack supplementation can increase testosterone and decrease cortisol compared to the typical decline in non-supplemented athletes and dieters. 9 - 10

Longjack supplementation appears to be safe. A human toxicology study administered 600 mg of longjack to participants daily for two months and found no effect on blood profiles, liver function, or kidney function. 11

Our Nimbus Men’s Health and Wellness test will analyze biomarkers related to testosterone and recommend a treatment plan consisting of Alpha Male X and other supplements, prescription medication, and lifestyle changes via our Discover You program. Our protocols typically include 300 to 600 mg of longjack, depending on your biomarkers. Order your testing kit today to get started on your hormone optimization journey.


1 Tambi MI, Imran MK, Henkel RR. Standardised water-soluble extract of Eurycoma longifolia, Tongkat ali, as testosterone booster for managing men with late-onset hypogonadism?. Andrologia. 2012;44 Suppl 1:226-230. doi:10.1111/j.1439- 0272.2011.01168.x

2 Rehman SU, Choe K, Yoo HH. Review on a Traditional Herbal Medicine, Eurycoma longifolia Jack (Tongkat Ali): Its Traditional Uses, Chemistry, Evidence-Based Pharmacology and Toxicology. Molecules. 2016;21(3):331. Published 2016 Mar 10. doi:10.3390/molecules21030331

3 Chaing HS, Merino-Chavez G, Yang LL, Wang FN, Hafez ES. Medicinal plants: conception/contraception. Adv Contracept Deliv Syst. 1994;10(3–4):355–63.

4 Chinnappan SM, George A, Pandey P, Narke G, Choudhary YK. Effect of Eurycoma longifolia standardised aqueous root extract-Physta® on testosterone levels and quality of life in ageing male subjects: a randomised, double-blind, placebo-controlled multicentre study. Food Nutr Res. 2021;65:10.29219/fnr.v65.5647. Published 2021 May 19. doi:10.29219/fnr.v65.5647

5 Talbott SM, Talbott JA, George A, Pugh M. Effect of Tongkat Ali on stress hormones and psychological mood state in moderately stressed subjects. J Int Soc Sports Nutr. 2013;10(1):28. Published 2013 May 26. doi:10.1186/1550-2783-10-28

6 Hamzah S, Yusof A. The ergogenic effects of Tongkat ali (Eurycoma longifolia): A pilot study. British J Sports Med. 2003;37:464–470.

7 Sarina MY, Zaiton Z, Aminudin AHK, Nor AK, Azizol AK. 4th Asia-Pacific Conference on Exercise and Sport Science & 8th International Sports Science Conference. Academy of Medicine of Malaysia; 2009. Effects of resistance training and Eurycoma longifolia on muscle strength, lipid profile, blood glucose, and hormone level in middle-aged women.

8 Ismail SB, Wan Mohammad WM, George A, Nik Hussain NH, Musthapa Kamal ZM, Liske ZM. Randomized clinical trial on the Use of PHYSTA freeze-dried water extract of eurycoma longifolia for the improvement of quality of life and sexual well-being in Men. Evid Based Complement Alternat Med; 2012.

9 Talbott S, Talbott J, Negrete J, Jones M, Nichols M, Roza J. Effect of eurycoma longifolia extract on anabolic balance during endurance exercise [abstract] J Int Soc Sports Nutr. 2006;3(1):S32.

10 Talbott S, Talbott J, Larsen W, Jackson V. Significant improvements in mood state and hormone profile associated with a “low-attrition” weight loss program. J Amer Coll Nutr. 2007;26(5):24.

11 Tambi MI, Kadir AA. Human toxicology and clinical observations of Eurycoma longifiola on men’s health. Int J Andrology. 2005;28(Suppl 1):37–38.

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