Ashwagandha Benefits: An Evidence-Based Review

Ashwagandha (Withania somnifera), also known as Indian ginseng or winter cherry, is an herb that has been used in traditional Ayurvedic medicine for centuries. This blog post will examine the latest research on ashwagandha's effectiveness for various health outcomes.

What is Ashwagandha?

Ashwagandha is an adaptogenic herb, meaning it may help the body manage stress. It contains compounds called withanolides, which are thought to be responsible for many of its health benefits [1].

Effectiveness for Various Health Conditions

Let's examine the evidence for ashwagandha's effectiveness in various aspects of health:

1. Stress and Anxiety Reduction: A 2014 systematic review by Pratte et al. analyzed five human trials and found that ashwagandha significantly reduced anxiety and stress. The review included studies using various anxiety scales, with one study showing a 56.5% reduction in anxiety scores compared to only 30.5% in the placebo group. Another study in the review found a 44% reduction in stress levels with ashwagandha compared to a 5.5% reduction with placebo [2].

   • Evidence Rating: Moderate to Strong

     • Consistent findings across multiple studies, but more large-scale trials are needed.

       
       

2. Improved Sleep: A 2019 study by Langade et al. involved 60 participants with insomnia. After 10 weeks, the ashwagandha group showed significant improvements in several sleep parameters. Sleep onset latency decreased by 39%, total sleep time increased by 33%, and sleep efficiency improved by 11%. Additionally, the study found a notable reduction in anxiety levels among participants [3].

   • Evidence Rating: Moderate

     • Several studies show positive effects, but more research is needed to confirm these findings across different populations.

       
       

3. Enhanced Athletic Performance: A 2015 study by Wankhede et al. involved 57 young male subjects engaging in resistance training for 8 weeks. The ashwagandha group showed significantly greater increases in muscle strength on bench-press (46% vs. 26.4% in placebo) and leg-extension (15.3% vs. 7.8% in placebo) exercises. They also demonstrated greater muscle size increases and a higher reduction in body fat percentage (3.5% vs. 1.5% in placebo) [4].

   • Evidence Rating: Limited to Moderate

     • While results are promising, more studies are needed to confirm these effects across different types of exercise and populations.

     
     

4. Cognitive Function: A 2017 study by Choudhary et al. involved 50 adults with mild cognitive impairment. After 8 weeks, the ashwagandha group showed significant improvements in immediate and general memory, executive function, attention, and information processing speed. For example, their scores on the Wechsler Memory Scale III improved by 95% compared to 25% in the placebo group [5].

   • Evidence Rating: Limited

     • More research is needed to determine the effects of ashwagandha on various aspects of cognitive function in different populations.

       
       

5. Thyroid Function: A 2018 study by Sharma et al. involved 50 subjects with subclinical hypothyroidism. After 8 weeks, the ashwagandha group showed significant improvements in thyroid indices. Serum TSH levels decreased by 17.5%, while T3 and T4 levels increased by 41.5% and 19.6% respectively. In comparison, the placebo group showed much smaller changes [6].

   • Evidence Rating: Limited

     • While promising, more studies are needed to confirm these effects and determine long-term safety.

       
       

6. Testosterone Levels and Male Fertility: A 2013 study by Ambiye et al. involved 46 male patients with oligospermia (low sperm count). After 90 days of treatment, the ashwagandha group showed a 167% increase in sperm count, a 53% increase in semen volume, and a 57% increase in sperm motility. Moreover, serum testosterone levels increased by 17% in the ashwagandha group [7].

   • Evidence Rating: Limited to Moderate

     • Several studies show positive effects, but more research is needed to confirm these findings in larger populations and to understand the mechanisms involved.

     
     

It's important to note that while ashwagandha shows promise in several areas, individual responses may vary. More high-quality human studies are needed to fully understand its effects.

Mechanisms of Action

Ashwagandha's effects are thought to be mediated through several mechanisms:

1. Stress Reduction: Ashwagandha may reduce cortisol levels and modulate stress response pathways [8].

2. Antioxidant Activity: The herb has potent antioxidant properties that may protect against cellular damage [9].

3. Hormonal Balance: Ashwagandha may influence various hormones, including thyroid hormones and testosterone [6,7].

   
   

Safety and Side Effects

Ashwagandha is generally considered safe when used as directed. However, some people may experience side effects such as:

• Gastrointestinal upset

• Drowsiness

• Headache

  
  

Long-term safety (beyond a few months) has not been well-established. Ashwagandha may not be suitable for pregnant women, those with autoimmune diseases, or people taking certain medications [12].

Recommended Dosing

Based on current research, the following dosing strategies are generally recommended:

• Stress and anxiety: 300-600 mg of a root extract daily, typically divided into two doses [2].

• Sleep improvement: 300-600 mg daily, taken 1-2 hours before bedtime [3].

• Athletic performance: 300-500 mg twice daily [4].

  
  

It's important to note that optimal dosing may vary depending on the specific health condition and individual factors.

Potential Interactions

While generally considered safe, ashwagandha may interact with certain medications:

1. Sedatives: Ashwagandha may increase the effects of sedative medications [13].

2. Thyroid Medications: Due to its effects on thyroid function, ashwagandha may interact with thyroid hormone replacement therapy [6].

3. Immunosuppressants: Ashwagandha may stimulate the immune system, potentially interfering with immunosuppressive drugs [14].

4. Blood Sugar Medications: Some research suggests ashwagandha may lower blood sugar levels, potentially interacting with diabetes medications [15].

   
   

Always consult with a healthcare provider before starting ashwagandha supplementation, especially if you're taking medications or have pre-existing health conditions.

Conclusion

Ashwagandha shows promise in several areas of health, particularly for stress and anxiety reduction, with moderate to strong evidence supporting its use in these areas. It also shows potential benefits for sleep improvement, athletic performance, and various other health outcomes, though more research is needed in many of these areas.

While generally safe, it's important to be aware of potential side effects and interactions, particularly for individuals with certain health conditions or those taking specific medications. As with any supplement, ashwagandha should be used as part of a comprehensive approach to health that includes proper nutrition, exercise, and stress management strategies.

Future research will likely provide more insights into ashwagandha's potential benefits and optimal use. For now, individuals interested in trying ashwagandha should consult with a healthcare professional to determine if it's appropriate for their specific health needs and goals.

References

1. Singh N, et al. (2011). An overview on ashwagandha: a Rasayana (rejuvenator) of Ayurveda. Afr J Tradit Complement Altern Med, 8(5 Suppl), 208-213.

2. Pratte MA, et al. (2014). An alternative treatment for anxiety: a systematic review of human trial results reported for the Ayurvedic herb ashwagandha (Withania somnifera). J Altern Complement Med, 20(12), 901-908.

3. Langade D, et al. (2019). Efficacy and Safety of Ashwagandha (Withania somnifera) Root Extract in Insomnia and Anxiety: A Double-blind, Randomized, Placebo-controlled Study. Cureus, 11(9), e5797.

4. Wankhede S, et al. (2015). Examining the effect of Withania somnifera supplementation on muscle strength and recovery: a randomized controlled trial. J Int Soc Sports Nutr, 12, 43.

5. Choudhary D, et al. (2017). Efficacy and Safety of Ashwagandha (Withania somnifera (L.) Dunal) Root Extract in Improving Memory and Cognitive Functions. J Diet Suppl, 14(6), 599-612.

6. Sharma AK, et al. (2018). Efficacy and Safety of Ashwagandha Root Extract in Subclinical Hypothyroid Patients: A Double-Blind, Randomized Placebo-Controlled Trial. J Altern Complement Med, 24(3), 243-248.

7. Ambiye VR, et al. (2013). Clinical Evaluation of the Spermatogenic Activity of the Root Extract of Ashwagandha (Withania somnifera) in Oligospermic Males: A Pilot Study. Evid Based Complement Alternat Med, 2013, 571420.

8. Chandrasekhar K, et al. (2012). A prospective, randomized double-blind, placebo-controlled study of safety and efficacy of a high-concentration full-spectrum extract of ashwagandha root in reducing stress and anxiety in adults. Indian J Psychol Med, 34(3), 255-262.

9. Bhattacharya SK, Muruganandam AV. (2003). Adaptogenic activity of Withania somnifera: an experimental study using a rat model of chronic stress. Pharmacol Biochem Behav, 75(3), 547-555.

10. Kuboyama T, et al. (2014). Neuritic regeneration and synaptic reconstruction induced by withanolide A. Br J Pharmacol, 171(4), 1032-1041.

11. Malik F, et al. (2009). Immunomodulatory activities of the ethanol extract of Withania somnifera roots in mice. J Chinese Integrat Med, 7(11), 1052-1058.

12. Tandon N, Yadav SS. (2020). Safety and clinical effectiveness of Withania Somnifera (Linn.) Dunal root in human ailments. J Ethnopharmacol, 255, 112768.

13. Mishra LC, et al. (2000). Scientific basis for the therapeutic use of Withania somnifera (ashwagandha): a review. Altern Med Rev, 5(4), 334-346.

14. Ziauddin M, et al. (1996). Studies on the immunomodulatory effects of Ashwagandha. J Ethnopharmacol, 50(2), 69-76.

15. Andallu B, Radhika B. (2000). Hypoglycemic, diuretic and hypocholesterolemic effect of winter cherry (Withania somnifera, Dunal) root. Indian J Exp Biol, 38(6), 607-609.