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Life Extension Magazine

LE Magazine December 2008

Natural Methods to Improve Vitality, Sexual Function, and Prostate Health

By Dale Kiefer

Nettle and Ginger

Stinging nettle and ginger are botanicals with a long history of human use. Both have been shown to possess significant anti-inflammatory activity.11,12

Nettle and Ginger

A controlled clinical trial of stinging nettle (Urtica dioica) root for the treatment of symptoms of benign prostatic hyperplasia (BPH, or prostate enlargement) showed, “Urtica dioica [has] beneficial effects in the treatment of symptomatic BPH. ”Specifically, six months of supplementation with nettle root led to decreased International Prostate Symptom Scores, improved peak urinary flow rate, and decreases in post-void residual volume of urine in the bladder. Additionally, the treated group experienced a modest decrease in prostate size. 22 Researchers speculate that this effect may be due to aromatase inhibition or anti-inflammatory activity.11

Nettle root may have further benefits for aging men’s health. Lignans contained in nettle root may help prevent the binding of sex hormone-binding globulin to testosterone. This may help ensure that free testosterone is available for promoting male vitality and youthful sexual function.8

A constituent of ginger shows promise in protecting prostate health with aging. In both laboratory and animal prostate cancer models, a ginger constituent helped to modulate proteins involved in apoptosis (programmed cell death).50

Norway Spruce Lignan Extract

Plant lignans have been shown to benefit humans in a variety of ways.10,29,51 The plant lignan hydroxymatairesinol (HMR), derived from Norway spruce, is metabolized to “enterolactone” in the gut where it is absorbed into the bloodstream.15 Higher levels of serum enterolactones in men have been associated with decreased prostate cancer risk.51 Recent research on human prostate tissue indicates that enterolactone restricts the proliferation of human prostate cancer in the laboratory.52

Norway Spruce Lignan Extract
Ginger root.

This has been confirmed by other researchers. “The mammalian lignan enterolactone is a major metabolite of plant-based lignans that has been shown to inhibit the growth and development of prostate cancer,” wrote Chinese researchers, recently. Working with prostate cancer cells in the laboratory, the scientists found that enterolactone, derived from plant lignans, caused cancer cells to undergo apoptosis, or controlled cellular suicide. “Our findings encourage further studies of enterolactone as a promising chemopreventive agent against prostate cancer,” the researchers concluded.23 Finnish researchers working with animal models of human prostate cancer also concluded, “… dietary HMR [lignan] started at the early phase of the tumor development inhibits the growth of… human prostate cancer xenografts in athymic male mice.”13

Enterolactone such as that derived from Norway spruce acts via numerous mechanisms to benefit aging men’s health. Increasing estrogen levels in aging men are believed to represent a significant culprit in the development of both benign prostate enlargement and prostate cancer.53 Enterolactone functions via several mechanisms to reduce estrogen levels.

Enterolactone inhibits the aromatase enzyme that is responsible for converting testosterone into estradiol (a potent estrogen).54,55 By inhibiting the aromatase enzyme, aging men can reduce excess estrogen while simultaneously increasing beneficial free testosterone.

Another enzyme involved in both benign and malignant prostate disease is 5-alpha reductase. The 5-alpha reductase enzyme converts beneficial testosterone into dihydrotestosterone (DHT), a potent metabolite. DHT provokes a stimulatory effect on both benign and malignant prostate cells.56

Enterolactones have been shown to inhibit 5-alpha reductase,57 thus reducing levels of DHT, which causes significant prostate discomfort in aging men. Not surprisingly, researchers have recently discovered that plant-derived lignans help relieve the symptoms of enlarged prostate in men.58


Thousands of years of safe human use, bolstered by modern scientific research, have shown that a variety of botanicals may positively impact sexuality and general well-being among aging men. While dwindling testosterone levels adversely affect men’s health, research has shown that it is possible to slow or reverse changes associated with the age-associated decline in circulating free testosterone while counteracting aging-related increases in estrogen levels, thus enhancing overall vitality and health.

If you have any questions on the scientific content of this article, please call a Life Extension Health Advisor at 1-800-226-2370.


1. Moffat SD. Effects of testosterone on cognitive and brain aging in elderly men. Ann NY Acad Sci. 2005 Dec;1055:80-92.

2. Beauchet O. Testosterone and cognitive function: current clinical evidence of a relationship. Eur J Endocrinol. 2006 Dec;155(6):773-81.

3. Martínez Jabaloyas JM, Queipo Zaragoza A, Ferrandis Cortes C, Queipo Zaragoza JA, Gil Salom M, Chuan Nuez P. Changes in sexual hormones in a male population over 50 years of age. Frequency of low testosterone levels and risk factors. Actas Urol Esp. 2008 Jun;32(6):603-10.

4. Yeap BB, Almeida OP, Hyde Z, et al. In men older than 70 years, total testosterone remains stable while free testosterone declines with age. The Health in Men Study. Eur J Endocrinol. 2007 May;156(5):585-94.

5. Yavuz BB, Ozkayar N, Halil M, et al. Free testosterone levels and implications on clinical outcomes in elderly men. Aging Clin Exp Res. 2008 Jun;20(3):201-6.

6. Maggi M, Schulman C, Quinton R, Langham S, Uhl-Hochgraeber K. The burden of testosterone deficiency syndrome in adult men: economic and quality-of-life impact. J Sex Med. 2007 Jul;4(4 Pt 1):1056-69.

7. Sternbach H. Age-associated testosterone decline in men: clinical issues for psychiatry. Am J Psychiatry. 1998 Oct;155(10):1310-8.

8. Anon. Urtica dioica; Urtica urens (nettle). Monograph. Altern Med Rev. 2007 Sep;12(3):280-4.

9. Piato AL, Detanico BC, Jesus JF, et al. Effects of Marapuama in the chronic mild stress model: further indication of antidepressant properties. J Ethnopharmacol. 2008 Jul 23;118(2):300-4.

10. Lamblin F, Hano C, Fliniaux O, et al. Interest of lignans in prevention and treatment of cancers. Med Sci (Paris). 2008 May;24(5):511-9.

11. Chrubasik JE, Roufogalis BD, Wagner H, Chrubasik S. A comprehensive review on the stinging nettle effect and efficacy profiles. Part II: urticae radix. Phytomedicine. 2007 Aug;14(7-8):568-79.

12. Grzanna R, Lindmark L, Frondoza CG. Ginger—an herbal medicinal product with broad anti-inflammatory actions. J Med Food. 2005;8(2):125-32.

13. Bylund A, Saarinen N, Zhang JX, et al. Anticancer effects of a plant lignan 7-hydroxymatairesinol on a prostate cancer model in vivo. Exp Biol Med (Maywood). 2005 Mar;230(3):217-23.

14. Kangas L, Saarinen N, Mutanen M, et al. Antioxidant and antitumor effects of hydroxymatairesinol (HM-3000, HMR), a lignan isolated from the knots of spruce. Eur J Cancer Prev. 2002 Aug;11(Suppl 2):S48-57.

15. Saarinen NM, Warri A, Makela SI, et al. Hydroxymatairesinol, a novel enterolactone precursor with antitumor properties from coniferous tree (Picea abies). Nutr Cancer. 2000;36(2):207-16.

16. Gonzales GF, Gasco M, Malheiros-Pereira A, Gonzales-Castaneda C. Antagonistic effect of Lepidium meyenii (red maca) on prostatic hyperplasia in adult mice. Andrologia. 2008 Jun;40(3):179-85.

17. McKay D. Nutrients and botanicals for erectile dysfunction: examining the evidence. Altern Med Rev. 2004 Mar;9(1):4-16.

18. Gonzales GF, Cordova A, Gonzales C, et al. Lepidium meyenii (Maca) improved semen parameters in adult men. Asian J Androl. 2001 Dec;3(4):301-3.

19. Mendes FR, Carlini EA. Brazilian plants as possible adaptogens: an ethnopharmacological survey of books edited in Brazil. J Ethnopharmacol. 2007 Feb 12;109(3):493-500.

20. Dording CM, Fisher L, Papakostas G, et al. A double-blind, randomized, pilot dose-finding study of maca root (L. Meyenii) for the management of SSRI-induced sexual dysfunction. CNS Neurosci Ther. 2008;14(3):182-91.

21. Brooks NA, Wilcox G, Walker KZ, et al. Beneficial effects of Lepidium meyenii (Maca) on psychological symptoms and measures of sexual dysfunction in postmenopausal women are not related to estrogen or androgen content. Menopause. 2008 Sep 6.

22. Safarinejad MR. Urtica dioica for treatment of benign prostatic hyperplasia: a prospective, randomized, double-blind, placebo-controlled, crossover study. J Herb Pharmacother. 2005;5(4):1-11.

23. Chen LH, Fang J, Li H, Demark-Wahnefried W, Lin X. Enterolactone induces apoptosis in human prostate carcinoma LNCaP cells via a mitochondrial-mediated, caspase-dependent pathway. Mol Cancer Ther. 2007 Sep;6(9):2581-90.

24. Beaumont DM, Mark TM Jr, Hills R, et al. The effects of chrysin, a Passiflora incarnata extract, on natural killer cell activity in male Sprague-Dawley rats undergoing abdominal surgery. AANA J. 2008 Apr;76(2):113-7.

25. Brown E, Hurd NS, McCall S, Ceremuga TE. Evaluation of the anxiolytic effects of chrysin, a Passiflora incarnata extract, in the laboratory rat. AANA J. 2007 Oct;75(5):333-7.

26. Zanoli P, Avallone R, Baraldi M. Behavioral characterisation of the flavonoids apigenin and chrysin. Fitoterapia. 2000 Aug;71(Suppl 1):S117-23.

27. Dhawan K, Kumar S, Sharma A. Beneficial effects of chrysin and benzoflavone on virility in 2-year-old male rats. J Med Food. 2002;5(1):43-8.

28. Konrad L, Müller HH, Lenz C, Laubinger H, Aumüller G, Lichius JJ. Antiproliferative effect on human prostate cancer cells by a stinging nettle root (Urtica dioica) extract. Planta Med. 2000 Feb;66(1):44-7.

29. Adlercreutz H. Lignans and human health. Crit Rev Clin Lab Sci. 2007;44(5-6):483-525.

30. Siqueira IR, Fochesatto C, Torres IL, et al. Antioxidant activities of Ptychopetalum olacoides (“muirapuama”) in mice brain. Phytomedicine. 2007 Nov;14(11):763-9.

31. Rowland DL, Tai W. A review of plant-derived and herbal approaches to the treatment of sexual dysfunctions. J Sex Marital Ther. 2003 May-Jun;29(3):185-205.

32. Gonzales GF, Cordova A, Vega K, et al. Effect of Lepidium meyenii (Maca), a root with aphrodisiac and fertility-enhancing properties, on serum reproductive hormone levels in adult healthy men. J Endocrinol. 2003 Jan;176(1):163-8.

33. Gonzales GF, Cordova A, Vega K, et al. Effect of Lepidium meyenii (MACA) on sexual desire and its absent relationship with serum testosterone levels in adult healthy men. Andrologia. 2002 Dec;34(6):367-72.

34. Gonzales GF, Miranda S, Nieto J, et al. Red maca (Lepidium meyenii) reduced prostate size in rats. Reprod Biol Endocrinol. 2005;35.

35. Gonzales GF, Vasquez V, Rodriguez D, et al. Effect of two different extracts of red maca in male rats with testosterone-induced prostatic hyperplasia. Asian J Androl. 2007 Mar;9(2):245-51.

36. Gasco M, Villegas L, Yucra S, et al. Dose-response effect of Red Maca (Lepidium meyenii) on benign prostatic hyperplasia induced by testosterone enanthate. Phytomedicine. 2007 Aug;14(7-8):460-4.

37. Vecera R, Orolin J, Skottova N, et al. The influence of maca (Lepidium meyenii) on antioxidant status, lipid and glucose metabolism in rat. Plant Foods Hum Nutr. 2007 Jun;62(2):59-63.

38. Oliveira CH, Moraes ME, Moraes MO, et al. Clinical toxicology study of an herbal medicinal extract of Paullinia cupana, Trichilia catigua, Ptychopetalum olacoides and Zingiber officinale (Catuama) in healthy volunteers. Phytother Res. 2005 Jan;19(1):54-7.

39. Waynberg J. Yohimbine vs. muira puama in the treatment of sexual dysfunction. Am J Nat Med. 1994;1:8-9.

40. da Silva AL, Piato AL, Bardini S, et al. Memory retrieval improvement by Ptychopetalum olacoides in young and aging mice. J Ethnopharmacol. 2004 Dec;95(2-3):199-203.

41. da Silva AL, Piato AL, Ferreira JG, et al. Promnesic effects of Ptychopetalum olacoides in aversive and non-aversive learning paradigms. J Ethnopharmacol. 2007 Feb 12;109(3):449-57.

42. Siqueira IR, Fochesatto C, da Silva AL, et al. Ptychopetalum olacoides, a traditional Amazonian “nerve tonic”, possesses anticholinesterase activity. Pharmacol Biochem Behav. 2003 Jun;75(3):645-50.

43. Moon YJ, Wang X, Morris ME. Dietary flavonoids: effects on xenobiotic and carcinogen metabolism. Toxicol In Vitro. 2006 Mar;20(2):187-210.

44. Cepa M, Correia-da-Silva G, da Silva EJ, et al. New steroidal aromatase inhibitors: suppression of estrogen-dependent breast cancer cell proliferation and induction of cell death. BMC Cell Biol. 2008;941.

45. van Meeuwen JA, Nijmeijer S, Mutarapat T, et al. Aromatase inhibition by synthetic lactones and flavonoids in human placental microsomes and breast fibroblasts—a comparative study. Toxicol Appl Pharmacol. 2008 May 1;228(3):269-76.

46. Burnett-Bowie SA, Roupenian KC, Dere ME, Lee H, Leder BZ. Effects of aromatase inhibition in hypogonadal older men: a randomized, double-blind, placebo-controlled trial. Clin Endocrinol (Oxf). 2008 Jun 25.

47. Leder BZ, Rohrer JL, Rubin SD, Gallo J, Longcope C. Effects of aromatase inhibition in elderly men with low or borderline-low serum testosterone levels. J Clin Endocrinol Metab. 2004 Mar;89(3):1174-80.

48. Walle T, Otake Y, Brubaker JA, Walle UK, Halushka PV. Disposition and metabolism of the flavonoid chrysin in normal volunteers. Br J Clin Pharmacol. 2001 Feb;51(2):143-6.

49. Srinivasan K. Black pepper and its pungent principle-piperine: a review of diverse physiological effects. Crit Rev Food Sci Nutr. 2007;47(8):735-48.

50. Shukla Y, Prasad S, Tripathi C, et al. In vitro and in vivo modulation of testosterone mediated alterations in apoptosis related proteins by [6]-gingerol. Mol Nutr Food Res. 2007 Dec;51(12):1492-502.

51. Hedelin M, Klint A, Chang ET, et al. Dietary phytoestrogen, serum enterolactone and risk of prostate cancer: the cancer prostate Sweden study (Sweden). Cancer Causes Control. 2006 Mar;17(2):169-80.

52. McCann MJ, Gill CI, Linton T, et al. Enterolactone restricts the proliferation of the LNCaP human prostate cancer cell line in vitro. Mol Nutr Food Res. 2008 May;52(5):567-80.

53. Takase Y, Levesque MH, Luu-The V, et al. Expression of enzymes involved in estrogen metabolism in human prostate. J Histochem Cytochem. 2006 Aug;54(8):911-21.

54. Brooks JD, Thompson LU. Mammalian lignans and genistein decrease the activities of aromatase and 17beta-hydroxysteroid dehydrogenase in MCF-7 cells. J Steroid Biochem Mol Biol. 2005 Apr;94(5):461-7.

55. Wang C, Makela T, Hase T, Adlercreutz H, Kurzer MS. Lignans and flavonoids inhibit aromatase enzyme in human preadipocytes. J Steroid Biochem Mol Biol. 1994 Aug;50(3-4):205-12.

56. Available at: Accessed October 3, 2008.

57. Evans BA, Griffiths K, Morton MS. Inhibition of 5 alpha-reductase in genital skin fibroblasts and prostate tissue by dietary lignans and isoflavonoids. J Endocrinol. 1995 Nov;147(2):295-302.

58. Zhang W, Wang X, Liu Y, et al. Effects of dietary flaxseed lignan extract on symptoms of benign prostatic hyperplasia. J Med Food. 2008 Jun;11(2):207-14.

59. Zitzmann M. Testosterone and the brain. Aging Male. 2006 Dec;9(4):195-9.

60. O’Connor DB, Archer J, Hair WM, Wu FC. Exogenous testosterone, aggression, and mood in eugonadal and hypogonadal men. Physiol Behav. 2002 Apr 1;75(4):557-66.

61. Seidman SN. Androgens and the aging male. Psychopharmacol Bull. 2007;40(4):205-18.

62. Bhasin S, Cunningham GR, Hayes FJ, et al. Testosterone therapy in adult men with androgen deficiency syndromes: an endocrine society clinical practice guideline. J Clin Endocrinol Metab. 2006 Jun;91(6):1995-2010.