Vitamin C: what it does, by goal, and the dose that worked
What the 536 human studies of vitamin c we graded show for each goal, the dose that worked, and the products that hold it. This page is educational, not medical advice.
What it does, by goalMembersThe top 5 of 26 goals
66 of these 536 human studies gave vitamin c by drip, injection or inhaler, not by mouth.
| Goal | What the studies show | Studies | Dose that worked |
|---|---|---|---|
| Improved in studies 61 studies, 29 showed an improvement, 7 found none, 5 pooled analyses, 26 by drip, injection or inhaler | 61 | 500 mg | |
| Improved in studies 35 studies, 20 showed an improvement, 2 found none, 5 pooled analyses | 35 | 3 % | |
| Improved in studies 28 studies, 17 showed an improvement, 1 found none, 5 pooled analyses | 28 | 0.2 % | |
| Improved in studies 30 studies, 16 showed an improvement, 5 found none, 1 pooled analysis, 6 by drip, injection or inhaler | 30 | 80 mg | |
| Improved in studies 44 studies, 15 showed an improvement, 5 found none, 7 pooled analyses, 4 by drip, injection or inhaler | 44 | 250 mg | |
| Improved in studies 25 studies, 14 showed an improvement, 2 found none, 4 pooled analyses | 25 | 3 % | |
| Improved in studies 35 studies, 12 showed an improvement, 11 found none, 6 pooled analyses, 1 by drip, injection or inhaler | 35 | 100 mg | |
| Improved in studies 24 studies, 12 showed an improvement, 3 found none, 5 pooled analyses | 24 | 3 | |
| Improved in studies 42 studies, 10 showed an improvement, 11 found none, 7 pooled analyses, 2 by drip, injection or inhaler | 42 | 80 mg | |
| Improved in studies 33 studies, 10 showed an improvement, 8 found none, 7 pooled analyses, 2 by drip, injection or inhaler | 33 | 70 mg | |
| Improved in studies 21 studies, 6 showed an improvement, 8 found none, 2 pooled analyses, 2 by drip, injection or inhaler | 21 | 60 mg | |
| Improved in studies 17 studies, 6 showed an improvement, 9 pooled analyses, 1 by drip, injection or inhaler | 17 | 50 mg | |
| Improved in studies 16 studies, 5 showed an improvement, 2 found none, 5 pooled analyses | 16 | 40 mg | |
| Improved in studies 11 studies, 4 showed an improvement | 11 | 3 g | |
| Improved in studies 7 studies, 4 showed an improvement, 1 by drip, injection or inhaler | 7 | – | |
| Improved in studies 14 studies, 2 showed an improvement, 4 found none, 1 by drip, injection or inhaler | 14 | 1 g | |
| Improved in studies 6 studies, 1 showed an improvement, 1 found none, 1 pooled analysis | 6 | – | |
| Improved in studies 3 studies, 1 showed an improvement | 3 | 1 g | |
| Improved in studies 1 study, it showed an improvement | 1 | – | |
| No effect in studies 55 studies, 15 showed an improvement, 21 found none, 6 pooled analyses, 9 by drip, injection or inhaler | 55 | 117 mg | |
| No effect in studies 63 studies, 6 showed an improvement, 28 found none, 6 pooled analyses, 19 by drip, injection or inhaler | 63 | 7 g | |
| No effect in studies 33 studies, 6 showed an improvement, 11 found none, 6 pooled analyses, 1 by drip, injection or inhaler | 33 | 500 mg | |
| No effect in studies 23 studies, 3 showed an improvement, 6 found none, 2 pooled analyses | 23 | – | |
| No effect in studies 18 studies, 3 showed an improvement, 9 found none, 3 pooled analyses, 1 by drip, injection or inhaler | 18 | 1 g | |
| No effect in studies 10 studies, 2 showed an improvement, 2 found none, 6 pooled analyses | 10 | – | |
| No effect in studies 9 studies, 1 showed an improvement, 2 found none, 1 pooled analysis, 1 by drip, injection or inhaler | 9 | – |
Members see which goal each result is for, and the products for it. Start My 7-Day Free Trial →
Products – highest ranked firstMembersThe top 3 of 43
Members see the products, their ranking and the reasons. Start My 7-Day Free Trial →
Dose and safetyThe dose that worked and the upper limit
The studies taken by mouth that showed an improvement gave 40 mg to 20 g a day.
The upper limit for adults is 2,000 mg of vitamin c a day; above it, members see a note and are told they can take less.
Biohacker panelMembersWhat our 10 biohackers say about vitamin c
Members see what each biohacker said. Start My 7-Day Free Trial →
Questions people askMembersAnswered from the figures on this page
What is vitamin c good for?
Answer for members.
How much vitamin c a day?
Answer for members.
Can I take vitamin c with my meds?
Answer for members.
Members see the answers, checked against their own meds and goals. Start My 7-Day Free Trial →
Educational, not medical advice. Figures come from the human studies on PubMed we have graded; a study counts for a form when it names the form it used. Updated as new studies arrive. How we grade →