Supplements for shift workers

The shift-worker stack — rationale by ingredient

Low-dose melatonin (0.3–0.5 mg) before day-sleep

Melatonin is the only supplement with chronobiotic evidence to support phase-shifting and improving day-sleep onset for night-shift workers. Use the low-dose — 0.3–0.5 mg has the cleanest circadian effect; the 5–10 mg sleep-aid doses commonly sold add sedation but do not work better for circadian alignment and have a longer half-life that bleeds into next-day function.

Magnesium glycinate 300–400 mg evenings (or before day-sleep)

Sleep maintenance and muscle relaxation; well-tolerated. Glycinate form contributes the mild GABA-A modulation of glycine itself.

Vitamin D3 to a 30–50 ng/mL 25-OH-D target

Night workers have substantially less daytime sun exposure than day workers; deficiency rates in occupational studies run higher than population norms. Test 25-OH-D and supplement to target. Particularly relevant in higher-latitude regions and during winter.

Caffeine, time-anchored to early-shift use

The most-evidenced alertness ergogenic in fatigued populations. Strategic — not constant — use. Keep within the first 4–5 hours of a night shift; later intake meaningfully impairs subsequent day-sleep.

L-Theanine + caffeine for sustained cognitive demand

200 mg L-theanine + 80–100 mg caffeine produces a smoother alertness profile with less jitter than caffeine alone — useful for the "cognitive marathon" portions of a night shift.

Glycine 3 g before day-sleep

Modest improvement in subjective sleep quality and next-shift alertness. Useful for shift workers whose dominant complaint is fragmented day-sleep.

Omega-3 EPA/DHA 1–2 g/day

Shift workers have meaningfully elevated cardiovascular risk relative to day workers; omega-3 is one of the better-evidenced cardiovascular adjuncts. Pair with an actual cardiovascular care plan rather than relying on supplements alone.

Iron repletion if ferritin is low

Test ferritin if fatigue is dominant or if you have RLS-style night symptoms (common in shift workers). Supplement only if low.