What is the recommended dose and frequency of ascorbic acid (Vitamin C)?

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Last updated: May 21, 2025View editorial policy

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From the Guidelines

The recommended daily dose of vitamin C for adults is 60-220 mg per day, depending on the health perspective and organization, with the most recent guidelines suggesting 60 mg/d as a sufficient amount to prevent scurvy 1. When considering the optimal dose and frequency of vitamin C supplementation, it's essential to take into account the individual's health status, dietary habits, and lifestyle.

  • The current recommended daily intake of vitamin C varies widely depending on the organization and health perspective, ranging from 40 to 220 mg per day 1.
  • For optimal health, some authorities recommend partly saturating immune cells with vitamin C, whilst limiting its urinary excretion, which may require higher doses 1.
  • However, the Food and Nutrition Board of the United States National Academy of Sciences recommends 60 mg/d as a sufficient amount to prevent scurvy, which is a widely accepted benchmark 1.
  • To maximize absorption, it's best to take vitamin C in divided doses throughout the day, as the body can only absorb a limited amount at a time.
  • Food sources like citrus fruits, bell peppers, and broccoli provide natural vitamin C along with other beneficial nutrients, and taking vitamin C with meals can reduce potential stomach upset.
  • Higher doses may be temporarily beneficial during illness, but should not be maintained long-term without medical supervision as they can cause digestive discomfort, diarrhea, or kidney stones in susceptible individuals.

From the FDA Drug Label

Directions Adults and Children 12 years and over: 500 mg (1 tablet) daily or as directed by your doctor Children under 12 years of age: Consult your doctor The recommended dose of vitamin C is 500 mg and the recommended frequency is daily for adults and children 12 years and over, as directed by a doctor 2.

  • For children under 12 years, the label advises to consult a doctor for dosage instructions 2.

From the Research

Vitamin C Dosage and Frequency

  • The required daily intake for vitamin C is ~60 mg, which can be found in one medium-sized orange 3
  • The current US recommended daily allowance (RDA) for ascorbic acid ranges between 100-120 mg/per day for adults 4
  • High doses of vitamin C, up to 500 mg daily, have been used to treat scurvy, a disease caused by vitamin C deficiency 3
  • Some studies suggest that high doses of vitamin C, above 1000 mg/day, may be associated with an increased risk of kidney stones in men, but not in women 5
  • Vitamin C has been shown to be a non-toxic and non-rate-limited antioxidant free radical scavenger, and high doses may be necessary to quench unwanted free radicals and oxidants 6

Administration and Efficacy

  • Vitamin C should be administered without hesitation in suspected cases of scurvy 3
  • Rapid clinical improvement with the resolution of skin lesions and joint contractures has been observed after the introduction of vitamin C in patients with scurvy 3
  • Vitamin C deficiency may be responsible for severe anemia, and supplementation may help alleviate this condition 3
  • The efficacy of vitamin C in preventing and treating various diseases, including cancer, is still a topic of debate and controversy 4

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Scurvy.

Acta dermatovenerologica Croatica : ADC, 2022

Research

Total, Dietary, and Supplemental Vitamin C Intake and Risk of Incident Kidney Stones.

American journal of kidney diseases : the official journal of the National Kidney Foundation, 2016

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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