Recommended Daily Vitamin C Intake
For healthy adults, you need 75 mg of vitamin C daily if you are a woman and 90 mg daily if you are a man, which can easily be obtained from 5 servings of fruits and vegetables per day. 1
Standard Daily Requirements
The recommended intake varies slightly by international authority, but converges around similar values:
- United States/Canada: 75 mg/day for women, 90 mg/day for men 2, 1
- European Union (EFSA): 95 mg/day for women, 110 mg/day for men 2, 1
- Minimum to prevent scurvy: 40-45 mg/day 2
If you smoke, add an additional 35 mg per day to these recommendations due to increased oxidative stress from cigarette smoke. 3
Special Populations Requiring Higher Intake
Pregnancy and Lactation
- Pregnant women: Add 10-20 mg/day to baseline requirements 2
- Lactating women: Add 20-60 mg/day to baseline requirements 2
After Bariatric Surgery
- Minimum intake: 75 mg/day for women, 90 mg/day for men 2
- Vitamin C should be taken concurrently with iron supplements to improve iron absorption 2
Chronic Disease States
Patients with chronic oxidative stress conditions may require 200-500 mg/day, though this should be under medical supervision. 1
Practical Dietary Sources
Foods high in vitamin C include citrus fruits (oranges, lemons, limes), tomatoes, and potatoes, making it straightforward to meet daily requirements through diet alone. 4
Upper Safety Limit
The tolerable upper intake level is 2,000 mg (2 grams) per day, above which gastrointestinal upset may occur. 5, 6 High intakes are generally well tolerated below this threshold. 7
Important Caveats
Absorption Limitations
- Oral vitamin C absorption becomes saturated at higher doses due to intestinal transporter limitations 1
- This means taking mega-doses orally provides diminishing returns
Populations Who Should Avoid High Doses
- Patients with hemochromatosis or iron overload conditions should avoid vitamin C supplementation, especially during iron depletion treatment phases, as vitamin C enhances iron absorption 5
When Testing Is Needed
- Plasma vitamin C testing is only recommended for suspected scurvy or documented chronic low intake 1
- Testing is unreliable during inflammation (when CRP >10 mg/L) 1
Clinical Bottom Line
Most healthy individuals can meet their vitamin C needs through a balanced diet containing 5 servings of fruits and vegetables daily, which provides approximately 200 mg of vitamin C. 8 Supplementation is unnecessary for most people eating a varied diet, but is safe up to 2,000 mg daily if desired. 5