Ashwagandha vs Maca for Stress: Complete 2026 Guide

TL;DR (Verdict-First)

Ashwagandha (Withania somnifera) and maca (Lepidium meyenii) are the two adaptogenic roots most often compared for stress support. They are not interchangeable. Ashwagandha has a deeper randomized-controlled-trial dataset on perceived stress scores and morning serum cortisol, with effects typically appearing at 250–600 mg/day over 8–12 weeks. Maca has a different evidence profile — its human trials lean toward mood, menopausal symptom relief, chronic-mountain-sickness score, energy, and sexual well-being — not direct cortisol suppression. Both show favorable structure/function signals in healthy adults, and both come with real caveats: ashwagandha has a growing case-report file of cholestatic liver injury, and the maca literature is dominated by small-to-moderate trials with limited methodological depth.

For a stress-seeker choosing an everyday coffee-based supplement, CafeBank routes to its 10g daily-driver blend (Active Blend VIP Coffee). That blend pairs maca and guarana — both extracted via supercritical CO2 (SFE), leaving zero solvent residue — with coffee. Maca is the right CafeBank-supported lever for most readers here because it pairs well with daily caffeine, doesn't carry the ashwagandha hepatotoxicity case-report pattern, and delivers the mood/energy/quality-of-life signal documented in its RCT base. Ashwagandha is not in any CafeBank SKU, so if you decide after reading this that direct cortisol work is what you need, you will source ashwagandha from a separate vendor — we will still tell you honestly what the literature says.

If you’re weighing ashwagandha against another adaptogen for daytime stress and mental fatigue rather than maca’s mood/energy lane, see also our rhodiola vs ashwagandha comparison — rhodiola has a different evidence profile (acute mental-fatigue and burnout endpoints) that some readers will find more relevant than the maca contrast covered here.

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

What the Research Actually Says

Ashwagandha (Withania somnifera) — Evidence Base

Stress, perceived stress, and morning cortisol

The ashwagandha stress literature clusters around a handful of 60–90 day randomized, double-blind, placebo-controlled trials in stressed but otherwise healthy adults. Three are load-bearing:

• Chandrasekhar 2012 (n=64, chronic stress) — 300 mg of a high-concentration full-spectrum root extract twice daily for 60 days vs placebo. The active arm showed significant reductions on every stress-assessment scale tested (P<0.0001) and a serum cortisol reduction of meaningful magnitude vs placebo (P=0.0006). Adverse events were mild and evenly distributed.
• Lopresti 2019 (n=60, self-reported high stress) — 240 mg/day of a standardized extract (Shoden) for 60 days. Significant Hamilton Anxiety Rating Scale reduction (P=0.040) and a robust morning-cortisol drop vs placebo (P<0.001). DHEA-S also decreased (P=0.004). Testosterone moved up within-males over time (P=0.038) but not compared with placebo (P=0.158) — the paper is explicit about that distinction.
• Salve 2019 (n=60, Perceived Stress Scale >20) — dose-response design, 250 mg/day and 600 mg/day vs placebo for 8 weeks. Both doses cut PSS scores (P<0.05 and P<0.001 respectively). Serum cortisol dropped at both doses (P<0.05 and P<0.0001). Sleep-quality improvement was significant in both active arms.

A fourth trial adds a cognitive layer: Gopukumar 2021 (n=130, PSS 14–24) tested 300 mg of a sustained-release formulation for 90 days and reported improvements in CANTAB recall memory, PSS-10, serum cortisol (P=0.0443), PSQI sleep score, and Oxford Happiness Questionnaire — with no adverse events in that cohort.

The practical read: across four independent trials, 250–600 mg/day of standardized ashwagandha root extract, taken for 8–12 weeks, is associated with a structure/function reduction in perceived-stress scores and a measurable drop in morning serum cortisol in stressed but non-clinical adults. This is the strongest single effect in the comparative field.

Sleep

Langade 2020 ran a parallel-group RCT in 80 participants (40 healthy, 40 with insomnia). Sleep onset latency (P<0.0001) and sleep efficiency (P<0.0001) were the parameters that moved most; effects were more pronounced in the insomnia arm than in healthy volunteers. Cheah 2021, a systematic review and meta-analysis of five ashwagandha sleep RCTs (400 total participants), found a small but statistically significant pooled effect on overall sleep (SMD -0.59; 95% CI -0.75 to -0.42; I²=62%). The meta-analysis authors flagged that effects were more prominent in the insomnia subgroup, at doses ≥600 mg/day, and at durations ≥8 weeks — and explicitly noted that long-term safety data are limited.

Safety profile — hepatotoxicity signal

The ashwagandha safety conversation changed after 2020. Björnsson 2020 reported five cases of liver injury attributed to ashwagandha-containing supplements (three from Iceland 2017–2018, two from the US Drug-Induced Liver Injury Network). Latency was 2–12 weeks; the pattern was cholestatic or mixed with prolonged jaundice and pruritus. Liver tests normalized in four of five within 1–5 months; no hepatic failure occurred in that cohort. Philips 2023 reported 23 ashwagandha-associated liver injury cases from multiple centers in India (2019–2022), including eight patients on single-ingredient formulations with no other supplements or hepatotoxic medications. Cholestatic hepatitis was the dominant presentation. In that series, three patients with pre-existing chronic liver disease developed acute-on-chronic liver failure and died on follow-up. Chemical analysis of the implicated formulations found only natural phytochemicals — no adulteration, no contamination.

The implication is not "ashwagandha is unsafe." The implication is that idiosyncratic cholestatic liver injury is a real, documented signal at population-exposure scale, and anyone with known chronic liver disease, who drinks heavily, or who is on other potentially hepatotoxic agents should treat this signal as a hard stop and consult a physician before starting ashwagandha.

Other caveats

• Pregnancy and breastfeeding: ashwagandha has traditional use as an emmenagogue and abortifacient in some Ayurvedic sources. It is routinely contraindicated in pregnancy and breastfeeding by practitioner texts and is not recommended in either population.
• Thyroid interaction: ashwagandha has documented thyroid-stimulating effects in both hyper- and hypothyroid contexts. In subclinical hypothyroid patients it has been studied for normalizing thyroid indices; conversely, case-level reports describe thyrotoxicosis in people with existing thyroid conditions. Anyone on levothyroxine or with active thyroid disease should coordinate with their physician before adding ashwagandha.
• Sedative and immunomodulator co-use: ashwagandha may potentiate GABAergic sedatives and has immunomodulatory effects; co-use with benzodiazepines, barbiturates, or immunosuppressants warrants medical supervision.

Maca (Lepidium meyenii) — Evidence Base

CafeBank uses supercritical CO2 (SFE) extraction for the maca in its blends. SFE operates above 31°C and 74 bar and leaves zero solvent residue — no ethanol, no hexane — which preserves heat-sensitive macamide and glucosinolate fractions that drive the herb's reported effects. Most of the maca literature cited below uses ethanolic, aqueous, or gelatinized preparations; CafeBank's SFE maca is positionally distinct from those commodity extracts, so read the trial data below as directional evidence on the herb, with extraction-method differentiation then applied on top.

Mood, energy, quality of life at altitude

Gonzales-Arimborgo 2016 is the most relevant mood/energy RCT. 175 adults living at low altitude and high altitude were randomized to placebo, red maca, or black maca spray-dried extract at 3 g/day for 12 weeks. Both maca arms improved mood, energy, and health-related quality-of-life score, and reduced chronic-mountain-sickness score vs placebo. Red maca edged black maca on mood, energy, and CMS-score endpoints. Black maca reduced blood glucose; neither extract reduced hemoglobin in low-altitude participants. No serious adverse events were reported.

Menopausal symptoms and psychological well-being

Brooks 2008 ran a randomized, double-blind, placebo-controlled crossover trial in 14 postmenopausal women. 3.5 g/day of powdered maca vs placebo for six weeks per arm. No change in estradiol, FSH, LH, or SHBG (P>0.05) — maca did not behave as a phytoestrogen. But Greene Climacteric Scale scores in the psychological-symptoms domain dropped significantly, including the anxiety and depression subscales, as did sexual-dysfunction measures (P<0.05). Complementary yeast-based reporter assays confirmed no physiologically meaningful estrogenic or androgenic activity, which is notable — the psychological effect appears to be independent of hormonal modulation.

Lee 2011 systematically reviewed four RCTs of maca for menopausal symptoms. All four reported favorable effects on the Kupperman Menopausal Index or Greene Climacteric Score. The review authors were explicit about the caveat: "the total number of trials, the total sample size, and the average methodological quality of the primary studies, were too limited to draw firm conclusions. Furthermore, the safety has not been proved yet." Translation: the directional signal is consistent, but the evidence base is not deep.

Sexual well-being and libido

Gonzales 2002 and its hormonal companion Gonzales 2003 are the foundational maca-and-sexual-desire RCTs. In the first, men aged 21–56 on 1,500 mg or 3,000 mg maca gelatinizada vs placebo for 12 weeks reported improved self-perception of sexual desire from week 8 — importantly, the effect was independent of Hamilton depression and anxiety scores. In the second paper, the same population's luteinizing hormone, follicle-stimulating hormone, prolactin, 17-OH-progesterone, testosterone, and 17β-estradiol were unchanged. Conclusion, verbatim: "treatment with Maca does not affect serum reproductive hormone levels." This matters for the structure/function frame — the libido effect is a subjective, measured endpoint; it is not a testosterone-pathway claim.

Dording 2008 is a small pilot in remitted depressed adults with SSRI-induced sexual dysfunction. 20 outpatients, randomized to 1.5 g/day or 3.0 g/day maca, 12 weeks. The 3.0 g arm showed significant improvement on both the Arizona Sexual Experience Scale (P=0.028) and the Massachusetts General Hospital Sexual Function Questionnaire (P=0.017). The 1.5 g/day arm did not. Ten subjects completed the trial — this is pilot-grade evidence, not a definitive finding.

Zenico 2009 treated 50 men with mild erectile dysfunction with 2,400 mg/day maca dry extract vs placebo for 12 weeks. Both groups improved on IIEF-5 (placebo response was real, P<0.05 within both arms), but the maca arm improved more (P<0.001 for the between-group delta), with additional gains on physical and social performance domains of the Satisfaction Profile.

Safety profile

Across the available RCTs, maca has been well tolerated. No serious adverse events reported in the 175-person altitude trial, no hepatotoxicity signal in PubMed case reports, and no measured change in serum reproductive hormones even at 3 g/day doses in young men. The cautious read is that the RCT base is small enough that long-tail safety events may still be under-detected — but unlike ashwagandha, there is no documented cholestatic-liver-injury case series attached to maca in the PubMed-indexed literature.

Caveats

• Pregnancy and breastfeeding: maca safety has not been established in either population. Clinical trials have excluded pregnant and breastfeeding participants. Do not use during pregnancy or while breastfeeding unless a physician has specifically evaluated and approved use.
• Thyroid-condition reading: maca is a Brassica — the cruciferous family includes documented goitrogenic plants. Individuals with active thyroid conditions should consult their physician before adding daily maca; practical clinical reports of thyroid disruption specifically from maca are rare in the indexed literature, but the class-level caution applies.
• Hormone-sensitive conditions: maca did not modulate serum reproductive hormones in the Gonzales trials, but individuals with hormone-sensitive cancers or on endocrine therapies should coordinate with their physician.

Head-to-Head Comparison

Mechanism

Ashwagandha's stress effect in the cited RCTs correlates with reduced morning serum cortisol and, in at least one trial, reduced DHEA-S — consistent with moderation of hypothalamus-pituitary-adrenal axis output. The authors of Lopresti 2019 are explicit that their findings "suggest that ashwagandha's stress-relieving effects may occur via its moderating effect on the hypothalamus-pituitary-adrenal axis" — phrased as a hypothesis, not a demonstrated mechanism.

Maca's psychological effects in the Brooks 2008 and Gonzales 2002 trials are explicitly not hormone-mediated. The Brooks trial's in-vitro reporter assays and the Gonzales 2003 endocrine panels both showed no measurable estrogenic, androgenic, or HPA-axis hormone changes. The working hypothesis in the maca literature centers on macamides and glucosinolate metabolites acting on endocannabinoid and neurotransmitter pathways, not on cortisol or sex hormones. That makes maca structurally different from ashwagandha: it is a mood/well-being modulator without direct cortisol-axis framing.

Onset and Half-Life

Both herbs operate on a slow-onset, chronic-dosing profile. Ashwagandha stress/cortisol endpoints move over 8–12 weeks in the cited trials — not hours. Maca's mood, sexual-desire, and menopausal-symptom endpoints also emerge at 6–12 weeks. Neither is an acute anxiolytic. Neither is dosed to effect in a single sitting.

Plasma pharmacokinetics in humans are not well characterized for either standardized extract at the trial doses cited. Don't expect a neat "half-life every 8 hours" dosing story; both are daily-dosing herbs with chronic cumulative exposure.

Dosing Windows

The two herbs are not dose-substitutable. Ashwagandha works in milligrams of a standardized extract. Maca works in grams of a whole-root powder or gelatinized/dry extract. CafeBank's 10g blend uses a supercritical-CO2 maca extract — the extraction method differs from the gelatinized or aqueous preparations used in most of the trials cited, which is why we flag the RCT data as directional herb-level evidence rather than a direct read-through on our SKU's exact extract.

Side-Effect Profiles

Both herbs are generally well tolerated in the RCTs cited. The asymmetry is in the post-marketing and case-series tail. Ashwagandha has an established cholestatic-hepatotoxicity case-series signal in both Western (Iceland/DILIN) and Indian single-center cohorts, with at least three reported deaths among patients with pre-existing chronic liver disease who developed acute-on-chronic failure. Maca has no equivalent signal in the PubMed-indexed case-report literature to our 2026-04-21 search date.

For someone with no pre-existing liver disease, no concurrent hepatotoxic medications, and no heavy alcohol use, ashwagandha's trial-level safety profile is benign. The risk population is narrow — but it's a real, documented narrow population.

Practical Stress-Support Routing (Where CafeBank Enters)

If the reason you're here is "I want a daily stress-support habit that fits my morning coffee," CafeBank's Active Blend VIP Coffee — our 10g daily-driver format — is the routing match. It pairs maca (supporting the mood, energy, and quality-of-life signal documented in the RCT base above) with guarana, a botanical caffeine source with its own documented literature on fatigue and well-being. Both herbs are extracted via supercritical CO2 (SFE), which operates without ethanol or hexane and leaves zero solvent residue. The result is a high-purity extract profile that preserves heat-sensitive actives — a technical rationale rather than a marketing slogan.

If you want the complete maca-on-coffee explainer with dosing, mechanism, and our published maca evidence read, the Maca Coffee Complete Guide is the parent pillar. For the deeper guarana evidence read, the Guarana vs Coffee Complete Guide has the RCT citations on guarana's fatigue and cognitive endpoints.

If you want tongkat ali in the mix — relevant for readers who want a male-vitality adaptogen alongside stress/mood support — that ingredient is not in the 10g blend. It is only in our flagship 20g format, Exclusive Blend VIP Coffee, and its evidence base is covered in the Tongkat Ali Coffee Complete Guide. We don't route tongkat ali content anywhere else — that routing is by design.

For the portable format without coffee, the VIP Coffee Tablets carry the same maca + guarana pair. How to get the most out of the daily-driver format is covered on the Active Blend usage page.

What CafeBank does not do: sell an ashwagandha-containing SKU. If your read of the evidence above is that you specifically want the cortisol-axis lever, you will need to source ashwagandha from another vendor — and we encourage you to pick a brand with published liver-safety QC and to consult your physician if you have any existing liver, thyroid, or pregnancy-related concern. That's not marketing hedge; that's the honest read of the safety signal.

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

Null Results and Limitations

Neither herb is a slam-dunk. Honest reading requires naming the strongest null and limitation for each.

Ashwagandha null / mixed result. The Cheah 2021 meta-analysis found a pooled effect on sleep of SMD -0.59 — statistically significant, but at the small-to-moderate end of effect sizes. Heterogeneity was substantial (I²=62%), and the authors wrote that "data on the serious adverse effects of Ashwagandha extract are limited, and more safety data would be needed to assess whether it would be safe for long-term use." On the stress side, Lopresti 2019 reported testosterone rose within-males over time (P=0.038) but the between-group comparison vs placebo was not significant (P=0.158) — a useful reminder that within-arm changes can look impressive while the controlled comparison says otherwise. None of these trials ran longer than 90 days, so claims about year-over-year benefit or safety are unsupported by the controlled evidence.

Maca null / mixed result. The foundational Gonzales 2003 trial is explicitly a null-result paper: serum luteinizing hormone, follicle-stimulating hormone, prolactin, 17-OH-progesterone, testosterone, and 17β-estradiol were unchanged by maca at 1.5 g/day or 3 g/day over 12 weeks. Claims that maca elevates hormone levels or balances endocrine output in healthy men are not supported by that controlled data — point to the Gonzales 2003 endocrine panel whenever you encounter them. Separately, the Lee 2011 systematic review of maca for menopausal symptoms — while directionally favorable across four RCTs — tells you explicitly that "the total number of trials, the total sample size, and the average methodological quality of the primary studies, were too limited to draw firm conclusions. Furthermore, the safety has not been proved yet." That is the maca evidence base's honest self-assessment. The Dording 2008 SSRI-sexual-dysfunction trial had only ten completers — pilot grade.

Both herbs deserve exactly the framing the literature gives them: directional, chronic-dosing, structure/function support in stressed-but-healthy adults, not a fix for a diagnosable condition.

FAQ

Can I take ashwagandha and maca together? The two herbs have non-overlapping mechanisms per the literature cited above, and there are no published interaction reports linking them. That said, no RCT has tested the combination, so you'd be outside the evidence base. Start one at a time; if you add the second, watch for any liver-related symptoms (fatigue, jaundice, dark urine, right-upper-quadrant discomfort) given the ashwagandha case-series signal.

Which one works faster for stress? Neither is acutely fast. The ashwagandha stress/cortisol trials measured endpoints at 60–90 days. The maca mood/energy trials measured at 6–12 weeks. If you want "I feel it in an hour," you are looking at the wrong pharmacology — consider caffeine, exercise, or clinical anxiolytics (under medical care), not adaptogens.

Can I take maca in the evening? Maca itself has no published stimulant profile in human RCTs. CafeBank's 10g format, however, contains both coffee and guarana — both are caffeine sources — so our blend is an AM or pre-workout drink, not an evening one. If you want a caffeine-free maca experience, the portable tablets also contain guarana, so the caffeine caveat applies. Plain maca powder from another source is caffeine-free.

Do I need to cycle these herbs? Neither the ashwagandha nor the maca RCTs ran long enough (>90 days for most) to give evidence-based cycling guidance. Traditional use varies. If you're treating this as daily support, re-evaluate at three months: how do you feel, what moved, any side-effect pattern. Coordinate with your physician for long-term use.

Is SFE (supercritical CO2) actually meaningful, or is that marketing? The distinction is real. Ethanol extraction leaves solvent residue and can denature heat-sensitive actives; hexane is a petrochemical solvent with its own residue risk; water struggles to pull fat-soluble actives. Supercritical CO2 extracts selectively, leaves zero residue after decompression, and preserves thermolabile compounds. Whether our SFE maca replicates the exact active profile of the gelatinized maca in Gonzales 2002 or the spray-dried extract in Gonzales-Arimborgo 2016 is a question the available literature does not answer directly — different extracts, different studies. We flag this honestly.

I'm pregnant or breastfeeding. What about just maca? Don't. Neither herb's safety has been established in pregnancy or breastfeeding. Clinical trials have excluded both populations. This is a hard stop, not a soft warning.

I have chronic liver disease. Can I take ashwagandha? Based on the Philips 2023 case series, no — not without specific clearance from your hepatologist. Three of the eight single-ingredient ashwagandha cases in that series had pre-existing chronic liver disease and developed acute-on-chronic liver failure with fatal outcome. This is the single population where the safety calculus shifts from "well tolerated at trial scale" to "documented serious risk."

Will maca lower my blood pressure or blood sugar? The Gonzales-Arimborgo 2016 trial reported that black maca reduced blood glucose in its 12-week cohort. That's one trial. Blood pressure was measured and did not move meaningfully. If you are on glucose-lowering medication or insulin, coordinate with your physician before daily maca use.

Disclaimer

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. Information in this article is educational and reflects the current state of the published literature as of April 2026. It is not a substitute for individualized medical advice. Consult a qualified healthcare practitioner before starting any supplement, especially if you are pregnant, breastfeeding, have a diagnosed medical condition, or take prescription medication.

References

1. Lopresti AL, Smith SJ, Malvi H, Kodgule R. (2019). An investigation into the stress-relieving and pharmacological actions of an ashwagandha (Withania somnifera) extract: A randomized, double-blind, placebo-controlled study. Medicine (Baltimore). 98(37):e17186. DOI: 10.1097/MD.0000000000017186. PMID: 31517876.
2. Chandrasekhar K, Kapoor J, Anishetty S. (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):255-62. DOI: 10.4103/0253-7176.106022. PMID: 23439798.
3. Salve J, Pate S, Debnath K, Langade D. (2019). Adaptogenic and Anxiolytic Effects of Ashwagandha Root Extract in Healthy Adults: A Double-blind, Randomized, Placebo-controlled Clinical Study. Cureus. 11(12):e6466. DOI: 10.7759/cureus.6466. PMID: 32021735.
4. Gopukumar K, Thanawala S, Somepalli V, Rao TSS, Thamatam VB, Chauhan S. (2021). Efficacy and Safety of Ashwagandha Root Extract on Cognitive Functions in Healthy, Stressed Adults: A Randomized, Double-Blind, Placebo-Controlled Study. Evid Based Complement Alternat Med. 2021:8254344. DOI: 10.1155/2021/8254344. PMID: 34858513.
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6. Cheah KL, Norhayati MN, Husniati Yaacob L, Abdul Rahman R. (2021). Effect of Ashwagandha (Withania somnifera) extract on sleep: A systematic review and meta-analysis. PLoS One. 16(9):e0257843. DOI: 10.1371/journal.pone.0257843. PMID: 34559859.
7. Philips CA, Valsan A, Theruvath AH, Ravindran R, Oommen TT, Rajesh S, Bishnu S, Augustine P. (2023). Ashwagandha-induced liver injury-A case series from India and literature review. Hepatol Commun. 7(10). DOI: 10.1097/HC9.0000000000000270. PMID: 37756041.
8. Björnsson HK, Björnsson ES, Avula B, Khan IA, Jonasson JG, Ghabril M, Hayashi PH, Navarro V. (2020). Ashwagandha-induced liver injury: A case series from Iceland and the US Drug-Induced Liver Injury Network. Liver Int. 40(4):825-829. DOI: 10.1111/liv.14393. PMID: 31991029.
9. Gonzales GF, Córdova A, Vega K, Chung A, Villena A, Góñez C, Castillo S. (2002). Effect of Lepidium meyenii (MACA) on sexual desire and its absent relationship with serum testosterone levels in adult healthy men. Andrologia. 34(6):367-72. DOI: 10.1046/j.1439-0272.2002.00519.x. PMID: 12472620.
10. Gonzales GF, Córdova A, Vega K, Chung A, Villena A, Góñez C. (2003). Effect of Lepidium meyenii (Maca), a root with aphrodisiac and fertility-enhancing properties, on serum reproductive hormone levels in adult healthy men. J Endocrinol. 176(1):163-8. DOI: 10.1677/joe.0.1760163. PMID: 12525260.
11. Brooks NA, Wilcox G, Walker KZ, Ashton JF, Cox MB, Stojanovska L. (2008). 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. 15(6):1157-62. DOI: 10.1097/gme.0b013e3181732953. PMID: 18784609.
12. Lee MS, Shin BC, Yang EJ, Lim HJ, Ernst E. (2011). Maca (Lepidium meyenii) for treatment of menopausal symptoms: A systematic review. Maturitas. 70(3):227-33. DOI: 10.1016/j.maturitas.2011.07.017. PMID: 21840656.
13. Dording CM, Fisher L, Papakostas G, Farabaugh A, Sonawalla S, Fava M, Mischoulon D. (2008). A double-blind, randomized, pilot dose-finding study of maca root (L. meyenii) for the management of SSRI-induced sexual dysfunction. CNS Neurosci Ther. 14(3):182-91. DOI: 10.1111/j.1755-5949.2008.00052.x. PMID: 18801111.
14. Zenico T, Cicero AFG, Valmorri L, Mercuriali M, Bercovich E. (2009). Subjective effects of Lepidium meyenii (Maca) extract on well-being and sexual performances in patients with mild erectile dysfunction: a randomised, double-blind clinical trial. Andrologia. 41(2):95-9. DOI: 10.1111/j.1439-0272.2008.00892.x. PMID: 19260845.
15. Gonzales-Arimborgo C, Yupanqui I, Montero E, Alarcón-Yaquetto DE, Zevallos-Concha A, Caballero L, Gasco M, Zhao J, Khan IA, Gonzales GF. (2016). Acceptability, Safety, and Efficacy of Oral Administration of Extracts of Black or Red Maca (Lepidium meyenii) in Adult Human Subjects: A Randomized, Double-Blind, Placebo-Controlled Study. Pharmaceuticals (Basel). 9(3):49. DOI: 10.3390/ph9030049. PMID: 27548190.

Citations retrieved from PubMed.