Vitamin C Intake Recommendations

While in 1993 the2013 the European Food Safety Authority (EFSA) set population reference intakes (PRI) for vitamin C (62)European nutrition societies, like the ones in Germany, Austria and Switzerland(D-A-CH) (63), referred to these values to define reference values for vitamin C intake (recommended intake). 

 Age   Males: mg/day Females: mg/day
 7-11 months 20 
Children and adolescents   
 1–3 years 20 
 4–6 years 30 
 7–10 years 45 
 11-14 years 70 
 15–17 years100 90
 18 years and older110 95
 Pregnant women
- 105
Lactating women- 155
a Smokers, D-A-CH
155 135

In 2013, EFSA stated that the average requirement (AR, applying to at least half of the population) to keep bodily vitamin C at healthy levels is an intake of 90 mg/day for men and 80 mg/day for women (63). The population reference intake (an ideal level for the majority of people) was set at 110 mg/day for men and 95 mg/day for women. These levels were sufficient, the expert panel said, to balance metabolic vitamin C losses and maintain fasting plasma ascorbate concentrations at about 50 micromoles/L (62).

In 2000, the U.S. Food and Nutrition Board revised the recommended dietary allowance (RDA) values for vitamin C upward, based primarily on the prevention of deficiency disease, rather than the prevention ofchronic disease and the promotion of optimum health. They used the near-maximal neutrophil concentration with minimal urinary excretion of ascorbate to provide antioxidant protection, which led them to define a Recommended Daily Allowances (RDA) (17).

RDA (mg/day) set by IoM:

 Life Stage  Age Males: mg/dayFemales: mg/day 
 0–6 months40 (AIa)40 (AI)
  7–12 months50 (AI)50 (AI)
  1–3 years1515
  4–8 years2525
 9–13 years4545
 14–18 years7565
 19 years and older9075
 19 years and older125110
 18 years and younger-80
 19 years and older-85
 18 years and younger-115
 19 years and older-120
a AI: Adequate intake   

The recommended intake for smokers is 35 mg/day higher than for non-smokers, because smokers are under increased oxidative stress from the toxins in cigarette smoke and generally have lower blood levels of vitamin C (17).

Up to now, no functional biomarker was identified that could be used as a basis to define the dietary intake recommendations for vitamin C. New evidence support neutrophil motility as such a functional marker. Combined with established knowledge from pharmacokinetic studies and studies on cardiovascular diseases and common cold, intake recommendations should be increased to ≥200 mg/day which would be beneficial for the functioning of the immune system (73).

For a detailed overview of recommended daily intakes (PRIs/RDAs) of vitamins and minerals for adults derived from different countries and organizations see PDF.

Authored by Dr Peter Engel in 2010, reviewed and revised by Dr. Volker Elste on 22.05.2017