Quick Comparison

5-HTPMaca Root
Half-Life2-5 hoursBioactive compounds accumulate with daily use
Typical DosageStandard: 50-200 mg daily. For mood: 50-100 mg 2-3 times daily. For sleep: 100-300 mg 30-60 minutes before bed. Start low — some people are very sensitive. Take with food to reduce nausea.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, tablets). Take with food to reduce GI side effects. Evening dosing preferred for sleep benefits.Oral (capsules, powder). Gelatinized for better digestion. Take in the morning.
Research Papers10 papers10 papers
Categories

Mechanism of Action

5-HTP

5-HTP readily crosses the blood-brain barrier via the large neutral amino acid transporter (LAT1/SLC7A5), unlike serotonin itself which cannot. Once in the brain, aromatic L-amino acid decarboxylase (AADC, also called DOPA decarboxylase) converts 5-HTP to serotonin (5-hydroxytryptamine) using pyridoxal-5-phosphate (active vitamin B6) as a cofactor. This completely bypasses tryptophan hydroxylase (TPH2), the rate-limiting enzyme in the normal serotonin synthesis pathway from dietary L-tryptophan. The result is a reliable, dose-dependent increase in serotonin across multiple brain regions including the dorsal raphe nucleus, hippocampus, and prefrontal cortex. Elevated serotonin activates 5-HT1A autoreceptors (calming), 5-HT2A/2C postsynaptic receptors (mood modulation), and 5-HT3 receptors (gut-brain signaling). In the pineal gland, serotonin is converted by arylalkylamine N-acetyltransferase (AANAT) to N-acetylserotonin, then by hydroxyindole O-methyltransferase (HIOMT) to melatonin — explaining the sleep-promoting effects.

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

5-HTP

Common

Nausea, diarrhea, stomach cramps.

Serious

Serotonin syndrome when combined with SSRIs, SNRIs, MAOIs, or tramadol — DO NOT combine without medical supervision.

Rare

Eosinophilia-myalgia syndrome (historical concern from contaminated L-tryptophan, not confirmed with modern 5-HTP).

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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