Creatine is among the most studied supplements. With resistance training, it reliably builds strength, power, and muscle size and helps preserve muscle in later life. Benefits for thinking under stress, mood, and bone are promising but weaker; lifespan and brain-protection claims are unproven. Safety is reassuring in healthy people, mainly some water weight. (Full Review)

Protocol

Standard Maintenance Dose

3–5 g/day

Creatine monohydrate, taken continuously; saturates muscle over ~3–4 weeks, no loading phase needed.

Loading (Optional)

~20 g/day, 5–7 days

Split into four 5 g doses, then 3–5 g/day maintenance; saturates muscle within about a week.

Brain / Older-Adult Dose

5–10 g/day

~0.1 g/kg body weight; cognitive protocols sometimes use 10–20 g/day. Larger individuals may need toward 10 g/day.

Time to effect

Strength & Power

3–4 weeks

Muscle saturation on 3–5 g/day; about 1 week with loading.

Cognition & Mood

Weeks to months

Where effects occur, they build gradually over weeks to months.

Bone Density

Months

Slower skeletal response, seen over longer-term use.

Benefits

High: Strength and power output; lean body mass and muscle size; high-intensity, repeated-effort exercise capacity

Medium: Muscle and functional preservation in older adults; cognitive performance under stress

Low: Adjunctive support for depressive symptoms; bone mineral density in older adults

Speculative: Longevity and healthspan extension; cardiovascular and metabolic support; neuroprotection in age-related cognitive decline

Contraindications

Significant chronic kidney disease (stage G4–G5, eGFR <30 mL/min)

Single functioning kidney

Active kidney injury

Key Interactions

Nephrotoxic drugs (NSAIDs, aminoglycosides, cyclosporine)

Diuretics (furosemide, hydrochlorothiazide)

High-dose caffeine

Stimulant pre-workouts

Bipolar disorder

Risk & Side Effects

High: Weight gain from water retention

Medium: Gastrointestinal discomfort

Low: Apparent rise in serum creatinine without kidney injury; muscle cramping and dehydration

Speculative: Hair loss via increased DHT; contaminant exposure from low-quality products

Monitoring

Marker	Target	Why
Cystatin C	~0.6–1.0 mg/L	Assesses true kidney filtration unaffected by creatine
Serum creatinine	~0.6–1.1 mg/dL	Detects meaningful renal change
eGFR	>90 mL/min/1.73 m²	Screens for reduced kidney function
Blood urea nitrogen (BUN)	~10–20 mg/dL	Complements kidney assessment and hydration status
Body weight / composition (DXA)	Rising lean mass	Tracks the primary muscle benefit and distinguishes water from fat
Creatine kinase (CK)	~30–200 U/L	Context for muscle status and recovery

Cadence: Baseline before starting, recheck kidney markers ~3 months after starting, then every 6–12 months; periodic body-composition and strength assessments.

Qualitative Assessment

Improved strength and training performance (heavier or more repetitions at the same effort)
Greater training capacity and faster between-set recovery
Stable or increasing lean mass over months
Subjective energy, cognitive clarity, or mood, particularly under sleep loss or stress
Absence of gastrointestinal discomfort at the chosen dose

Creatine for Health & Longevity

Protocol

Benefits

Risk & Side Effects

Monitoring

Qualitative Assessment