K2
People mainly take K2 for skin & hair, mood, libido. Based on 15 first-hand reports. Ranked #928 of 1,974 overall.
18
User score
Mixed13% positive7% mixed7% negative73% unclear
Of reports that state an outcome, 48% are positive.
Clinical research
Research pending
What K2 does, according to users
Of the people who reported each effect, the share who said it got better.
betterno changeworse
What the research says
Systematic reviews and meta-analyses from PubMed, with their published conclusions.
Research data for K2 is being compiled.
Dosage people report
As stated by users — not a recommendation. Follow the label or your doctor.
45 mcg per 1000 IU D3as reported
45 mgdaily
100 mcgdaily
dailyas reported
Reported side effects
How often each side effect came up across all reports.
depression ×1
What users say
Verbatim quotes, shortened only — each links to the original discussion.
“but k2 (mk7), d3 5000 iu when I done grey enough sun (which is almost daily)”
“i believe k2, B vitamins, and amino acids L carnitine and glutamine made a difference in my skin.”
“If you're supplementing D3, make sure to either up your nutritional sources of K2 or supplement with K2 to ensure absorption of the D3.”
“not noticeable for me: K2, copper, selenium, vitamin E, isolated B vitamins”
“Make sure you are taking Magnesium (glycinate, taurate or malate) and K2 (MK7) with it.”
Other options for skin & hair
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Mostly positiveCResearch: Limited
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Exercise
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100% report better skin & hair
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Klow
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100% report better skin & hair
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Black Seed Oil
Supplement · 111 reports
67% report better skin & hair
Mostly positiveBResearch: Moderate
Creatine
Supplement · 782 reports
12% report better skin & hair
Mostly positiveAResearch: Strong
User data from public discussions; research from PubMed. Information only, not medical advice — talk to a doctor before starting, stopping or combining anything. Data updated October 2, 2026. How we rate