Ashwagandha
Ashwagandha (Withania somnifera), also known as Winter Cherry, has long been touted as the best rejuvenative in the Ayurvedic pharmacopeia. It is a small evergreen shrub that produces small fruits that turn orangish-red when ripe. It is the roots that contain the medici-nal effect, however, and have been used for millennia in Ayurvedic, Unani, and African medicine. Understanding the benefcial tonifying effects of Ashwagandha helps us understand how stress, overwork, and adrenal fatigue affect our reproductive organs, libido, immunity, and vitality. Ojas (a vital energy) is depleted by anger, worry, and sorrow, as well as overwork and overstimulation. Ashwagandha increases vital energy by strengthening the reproductive organs. The vital energy generated in the reproductive organs creates a reserve that in turn feeds other systems of the body that are responsible for combating stress, our immunity and well-being.
In the brain Ashwagandha seems to affect GABA receptors, thus inhibiting the signals caused by stress and reducing anxious feelings. The root may also contain levels of tryptophan which is a serotonin precursor, and thus can help regulate mood.
Withanolides can be shown in cellular studies to reduce the markers of stress and infammation 1,5,7,, thus affecting behavioral, endocrine, and immunological health.
And in a 2013 study, reduction of stress-related physiological markers by Withania somnifera root extract also resulted in improved memory.
How Withania somnifera improves fertility is less clear, but results show that hormonal markers and indicators of semen quality are improved by strong doses of root powder. Improved antioxidant levels tend to accompany these results, and 14% of participants successfully fathered a pregnancy due to treatment.
Aerobic endurance measured as cardiorespiratory function was shown to be improved in elite cyclists in an Indian study conducted in 2012. They took 500mg of aqueous root extract twice daily for 8 weeks, and showed signifcant improvement relative to their baseline parameters 8 weeks prior.
Ashwagandha is touted to slow aging by building blood, muscle, and bone, as well as by modulating the stress and hormonal triggers in the body. Memory loss and cognitive impairment due to oxidative damage from stress and aging have shown improvement in numerous scientific and case studies.
Ashwagandha has long been used in doses of root powder from 250mg to 5 g twice daily. Most recommendations today are for aqueous root extracts standardized to 4.5% or more Withanolides in dosages of 250-300mg per capsule, 2-3 times a day.
Ayurveda cautions against using Ashwagandha when gastric ulcers are present, liver enzymes are high, when pregnant and breastfeeding, and suggests consulting an endocrinologist if under care for thyroid disorders, as it can affect the activity of thyroid hormones.
Other studies:
Ws root powder at 5g a day reduced reported stress, improved antioxidant levels, and improved overall semen quality in male subjects.
Dried aqueous extract of roots and leaves shown to improve cognitive and psychomotor performance and shows usefulness in conditions of cognitive impairments.
References:
1. Kour K, Pandey A,. “Restoration of stress-induced altered T cell function and corresponding cytokines patterns by Withanolide A.” Int Immunopharmacol. 2009 Sep;9(10):1137-44. doi: 10.1016/j.intimp.2009.05.011. Epub 2009 Jun 12.
2. Baitharu I, Jain V. “Withania somnifera root extract ameliorates hypobaric hypoxia induced memory impairment in rats.” J Ethnopharmacol. 2013 Jan 30;145(2):431-41. doi: 10.1016/j.jep.2012.10.063. Epub 2012 Dec 2
3. Mahdi AA, Shukla KK. “Withania somnifera Improves Semen Quality in Stress-Related Male Fertility.” Evid Based Complement Alternat Med. 2009 Sep 29.
4. Shenoy S, Chaskar U. “Effects of eight-week supplementation of Ashwagandha on cardiorespiratory endurance in elite Indian cyclists.” J Ayurveda Integr Med. 2012 Oct;3(4):209-14. doi: 10.4103/0975-9476.104444
5. Ahmad MK, Mahdi AA. “Withania somnifera improves semen quality by regulating reproductive hormone levels and oxidative stress in seminal plasma of infertile males.” Fertil Steril. 2010 Aug;94(3):989-96. doi: 10.1016/j.fertnstert.2009.04.046. Epub 2009 Jun 6
6. Bhattacharya SK, Muruganandam AV. “Adaptogenic activity of Withania somnifera: an experimental study using a rat model of chronic stress.” Pharmacol Biochem Behav.2003 Jun;75(3):547-55
7. Pingali U, Pillli R, Fatima N. “Effect of standardized aqueous extract of Withaniasomnifera on tests of cognitive and psychomotor performance in healthy human participants.” Pharmacognosy Res. 2014 Jan;6(1):12-8. doi: 10.4103/0974-8490.122912
8. Chengappa KN, Bowie CR. “Randomized placebo-controlled adjunctive study of an extract of withania somnifera for cognitive dysfunction in bipolar disorder.” J Clin Psychiatry. 2013 Nov;74(11):1076-83. doi: 10.4088/JCP.13m08413
9. Chandrasekhar K, Kapoor J.“A prospective, randomized double-blind, placebo-controlled study of safety and effcacy of a high-concentration full-spectrum extract of ashwagandha root in reducing stress and anxiety in adults.” Indian J Psychol Med. 2012 Jul;34(3):255-62. doi: 10.4103/0253-7176.106022