Quick Comparison

AshwagandhaMaca Root
Half-Life6-12 hours (withanolides)Bioactive compounds accumulate with daily use
Typical DosageKSM-66 extract: 300-600 mg daily. Sensoril extract: 125-250 mg daily. Root powder: 3-6 g daily. Best taken with food. Can be taken morning or evening (does not cause drowsiness in most people).Standard: 1500-3000 mg daily of extract (or 5-10 grams of raw powder). Red maca: best for prostate health and bone density. Black maca: best for cognition, endurance, and sperm quality. Yellow maca: most common, general adaptogen. Gelatinized maca is easier to digest. Take in the morning. Effects build over 2-6 weeks.
AdministrationOral (capsules, powder). Standardized extracts (KSM-66 or Sensoril) are preferred over raw root powder for consistent dosing.Oral (capsules, powder). Gelatinized for better digestion. Take in the morning.
Research Papers9 papers10 papers
Categories

Mechanism of Action

Ashwagandha

Ashwagandha's withanolide compounds (withaferin A, withanolide A, withanone) modulate the hypothalamic-pituitary-adrenal (HPA) axis, reducing corticotropin-releasing hormone (CRH) and adrenocorticotropic hormone (ACTH) signaling, thereby lowering cortisol production by 25-30% in stressed individuals. It acts as a GABA-A receptor positive allosteric modulator at the benzodiazepine site, producing anxiolytic effects without sedation. Ashwagandha inhibits acetylcholinesterase (AChE), raising acetylcholine levels in the hippocampus and cortex. The withanolides have anti-inflammatory properties via inhibition of NF-κB and COX-2, and antioxidant effects that reduce neuroinflammation and oxidative stress. It may support neurogenesis through upregulation of BDNF and its receptor TrkB, and modulation of the PI3K/Akt pathway.

Maca Root

Macamides (N-benzyl fatty acid amides like macamide N-benzylhexadecanamide) and macaenes are unique compounds that inhibit fatty acid amide hydrolase (FAAH), increasing anandamide levels and modulating the endocannabinoid system — providing mood and stress resilience without CB1/CB2 direct activation. Maca improves endocrine signaling through the hypothalamic-pituitary-adrenal and hypothalamic-pituitary-gonadal axes, normalizing CRH, ACTH, and gonadotropin release without directly altering hormone levels. Glucosinolates (glucotropaeolin) support antioxidant defense via Nrf2. The cognitive effects of black maca are attributed to improved cerebral blood flow (possibly via eNOS), acetylcholinesterase (AChE) inhibition increasing acetylcholine, and reduced oxidative stress. The energy effects may involve improved mitochondrial function (Complex I), glucose metabolism (GLUT4, hexokinase), and dopaminergic tone.

Risks & Safety

Ashwagandha

Common

Gastrointestinal discomfort, drowsiness at higher doses, thyroid hormone elevation.

Serious

Can cause hyperthyroidism in susceptible individuals — avoid with thyroid conditions without medical oversight. Rare liver injury reports.

Rare

Vertigo, nasal congestion, sexual dysfunction.

Maca Root

Common

GI discomfort with raw powder (gelatinized form is gentler), insomnia if taken late.

Serious

May be contraindicated with hormone-sensitive conditions (theoretical, no direct hormonal activity proven).

Rare

Headache, mood changes. Goitrogen concerns at very high doses.

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