Vitamin C and Infection Prevention Guidelines

Introduction to Vitamin C Recommendations

The American College of Nutrition recommends against using high-dose vitamin C as monotherapy for infection prevention in healthy individuals, as there is no evidence supporting this practice, with a Grade B recommendation and 96% consensus 1
The Clinical Nutrition society advises that antioxidants, including vitamin C, should not be administered without proven deficiency, representing a clear directive from major clinical nutrition guidelines regarding prophylactic high-dose vitamin C use 1

The Clinical Nutrition guidelines state that doses exceeding 10 times the dietary reference intake should not be used in clinical settings without proven severe deficiency, emphasizing the importance of tailored supplementation 1
Malnourished patients should receive supplementation with vitamins and minerals, including vitamin C, to maximize anti-infection nutritional defense, as recommended by the Clinical Nutrition society 2
The Clinical Nutrition society recommends repletion therapy with appropriate doses of vitamin C for documented deficiency states, continuing until nutritional status is restored 2

Absolute contraindications to high-dose vitamin C include hemochromatosis or iron overload conditions, G6PD deficiency, renal dysfunction, and history of oxalate kidney stones, as outlined by the Clinical Nutrition guidelines 3
The Clinical Nutrition society advises against measuring plasma vitamin C during acute illness, as inflammation makes interpretation unreliable 3

The Clinical Nutrition society recommends assessing nutritional status and risk factors, including malnourishment, physical activity, and physiologic stress, to determine the need for vitamin C supplementation 2
For well-nourished, healthy individuals, the Clinical Nutrition guidelines recommend ensuring adequate dietary intake of 100-200 mg/day and avoiding high-dose supplementation for infection prevention 1
For at-risk populations, including malnourished and physically active individuals, the Clinical Nutrition society recommends providing daily allowances to ensure adequate intake and considering 200-500 mg/day for those with documented increased requirements 2