Melatonin vs Vitamin K2 (MK-7)
Sleep vs Vitamin · evidence-backed comparison
- • Melatonin has the stronger evidence base (strong (multiple rcts / meta-analyses)).
- • Melatonin has the broader effect profile across the 9 effect categories.
- • Melatonin is cheaper per serving ($0.05 vs $0.18).
- • Vitamin K2 (MK-7) has higher bioavailability (better absorption).
Side-by-side traits
| Trait | Melatonin | Vitamin K2 (MK-7) |
|---|---|---|
Category | Sleep | Vitamin |
Active compound | N-acetyl-5-methoxytryptamine | Menaquinone-7 |
Form available | Capsule, Tablet, Liquid, Gummy | Softgel, Capsule |
Source | synthetic | microbial |
Typical dose | 0.3–3 mg | 100–200 mcg daily |
Dose range | 0.3–3 mg | 100–200 mcg |
Loading protocol | — | — |
Best taken with | 30–60 min before bed | fat-containing meal |
Best time of day | evening | any |
Bioavailability How efficiently the body absorbs and utilizes the compound. | Moderate (3/5) | High (4/5) |
Onset time | Acute: 30–60 min | Cumulative: 4–12 weeks |
Half-life | 20–50 min | ~72 hours |
Evidence level Quality and quantity of human research. | Strong (multiple RCTs / meta-analyses) | Moderate (some RCTs) |
Overall effect Subjective effect magnitude. | Moderate (3/5) | Low (2/5) |
Muscle / strength | Very Low (1/5) | Very Low (1/5) |
Physical energy | Very Low (1/5) | Very Low (1/5) |
Focus / cognition | Very Low (1/5) | Very Low (1/5) |
Mood / stress | Low (2/5) | Very Low (1/5) |
Sleep quality | Very High (5/5) | Very Low (1/5) |
Immunity | Low (2/5) | Low (2/5) |
Recovery Post-exercise recovery support. | Moderate (3/5) | Low (2/5) |
Longevity / healthspan | Moderate (3/5) | High (4/5) |
Safety rating 5 = exceptionally well-tolerated; 1 = significant risk profile. | High (4/5) | High (4/5) |
Price per serving Approximate USD per typical daily dose. | $0.05 | $0.18 |
Vegan friendly | Yes | Yes |
Gluten free | Yes | Yes |
3rd-party tested | Yes | Yes |
About Melatonin
Pineal-gland hormone that signals 'night-time' to the body. Most useful for jet lag and shifted sleep schedules; lower doses (0.3 mg) often work better than 5–10 mg.
About Vitamin K2 (MK-7)
Activates osteocalcin and matrix-Gla protein to direct calcium into bones rather than arteries. Most evidence comes from the 3-year Rotterdam study.
Vetted brands, third-party testing, ships worldwide.
Vetted brands, third-party testing, ships worldwide.
Melatonin safety
Common side effects:
- • Vivid dreams
- • Morning grogginess (high doses)
- • Headache
Avoid if:
- • Autoimmune disease
- • Pregnancy
- • Driving for hours after
Drug interactions:
- • Birth control
- • Anticoagulants
- • Antidepressants
- • Diabetes meds
Vitamin K2 (MK-7) safety
Common side effects:
- • Generally none
Avoid if:
- • Warfarin therapy
Drug interactions:
- • Warfarin (major)
- • Other anticoagulants
Common uses
- • Jet lag
- • Shift work
- • Sleep onset
- • Circadian rhythm
Stacks well with: Magnesium Glycinate, Glycine
Common uses
- • Bone density
- • Arterial health
- • Calcium routing
Stacks well with: Vitamin D3, Magnesium Glycinate
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Medical disclaimer
SupplementDuel is for educational purposes only and is not medical advice. Consult a physician before starting, stopping, or combining supplements — especially if you are pregnant, breastfeeding, take prescription medication, or have a chronic condition.