Vitamin C
Also known as Ascorbic acid, L-ascorbic acid
Vitamin C is a water-soluble vitamin and antioxidant that the body cannot make or store, so it must come from the diet. It is needed to build collagen and to support immune defenses.
The recommended intake sits at about 5% of the level considered the safe daily ceiling, leaving comfortable headroom.
Why it matters
What it does in your body
- Antioxidant
- Collagen synthesis
- Immune function
- Wound healing
- Improves absorption of non-heme (plant) iron
- Synthesis of neurotransmitters and carnitine
By age, sex, and life stage
How much you need
Values are RDAs except for infants, which are Adequate Intakes (AI). People who smoke need an extra 35 mg/day beyond the listed amount because smoking increases oxidative stress and vitamin C turnover.
Recommended intake across life
in mg/dayBars scale to the highest recommendation shown. Where men and women differ, both values are listed.
Full reference table
| Life stage | Male | Female |
|---|---|---|
| Infants 0-6 mo | 40 (AI) | 40 (AI) |
| Infants 7-12 mo | 50 (AI) | 50 (AI) |
| Children 1-3 | 15 | 15 |
| Children 4-8 | 25 | 25 |
| Children 9-13 | 45 | 45 |
| Teens 14-18 | 75 | 65 |
| Adults 19+ | 90 | 75 |
| Pregnancy | n/a | 85 (80 if 14-18) |
| Lactation | n/a | 120 (115 if 14-18) |
Values in mg/day. AI marks an Adequate Intake, used when there is not enough evidence for a formal recommendation.
What moves the number
What changes your needs
Age
Needs rise steadily from 15 mg/day in early childhood to 90 mg/day (men) and 75 mg/day (women) in adulthood.
Sex
Adult men need 90 mg/day and adult women need 75 mg/day, reflecting differences in body size.
Body weight / size
Larger body size raises requirements, which is part of why the male RDA exceeds the female RDA.
Pregnancy and lactation
Pregnancy raises the need to 85 mg/day and lactation to 120 mg/day to support the fetus and milk production.
Smoking
Smokers need 35 mg/day more than the listed RDA due to greater oxidative stress and faster vitamin C turnover.
Running low
Signs you might not get enough
Most at risk: People who smoke or are exposed to secondhand smoke, those with very limited diet variety, people with malabsorption or certain chronic diseases, patients on hemodialysis for end-stage renal disease, and infants fed evaporated or boiled cow's milk.
Too much
Can you get too much?
Adverse effects come mainly from supplements, not food. The most common complaints are diarrhea, nausea, and abdominal cramps, which usually resolve when the dose is lowered.
Where to get it
Best food sources
The bottom line
Eat a variety of fruits and vegetables and most people easily meet their vitamin C needs. Adults should aim for 75 to 90 mg/day, and smokers should add 35 mg/day.
Track vitamin c automatically
Vitamin C is one of the 92 nutrients Vora reads from a photo of your meal, so you can see where you stand without weighing or logging by hand.
Sources and method
The recommended intakes, upper limits, and food-source amounts on this page come from the primary references below. Numbers were checked against the current NIH Office of Dietary Supplements fact sheets and the Institute of Medicine (now the National Academies) Dietary Reference Intakes.
- NIH Office of Dietary Supplements, Vitamin C Fact Sheet for Health Professionals
- Institute of Medicine (IOM/NASEM), Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids (2000)
This page is for general education, not medical advice. Reference intakes are population averages for healthy people and do not replace guidance from your doctor or a registered dietitian, especially if you are pregnant, managing a health condition, or considering supplements.