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Head-to-head · sleep

Magnesium vs. CBT-I for Insomnia

Outcome compared: Insomnia & sleep onset

The verdict

Not a close call. CBT-I has a far larger and more consistent evidence base (30 RCTs, medium-large sustained effects) than magnesium (3–8 small RCTs, a small effect that may not exceed placebo response). CBT-I requires more upfront effort; magnesium requires none — but the evidence doesn't support magnesium as a substitute for behavioral treatment for real insomnia.

The gapLarge gap (A- vs. C) — one of the clearest 'pill vs. practice' mismatches in the database so far.

C
Magnesium Bisglycinate
supplementsleep

Best evidence: CPreliminary / mixed

Evidence grade
C
Effect size
Small (d ≈ 0.2); ~17 min faster onset
Evidence base
3–8 small RCTs (~150 each); low quality
Effort
None — a daily capsule
Cautions
Caution with kidney impairment, some meds
A-
CBT-I (Cognitive Behavioral Therapy for Insomnia)
practicesleep

Best evidence: A-Strong evidence

Evidence grade
A−
Effect size
Medium–large (g = 0.64 at 3 mo), sustained to 12 mo
Evidence base
30 RCTs; replicated across populations
Effort
4–8 structured sessions
Cautions
Temporary daytime sleepiness during sleep restriction

Grade badges show each intervention's strongest evidence across all its outcomes. Tap a name for the full entry.