Vitamin C in health and disease.
Level 5 - mechanism / opinion, no new human data
Narrative review synthesizing established nutritional knowledge without primary human trials or systematic search methodology.
What was done
Narrative review examining the physiological roles, bodily storage capacities, deficiency timelines, recommended dietary allowances, and upper intake thresholds for vitamin C and other essential vitamins.
What was found
Body stores of vitamins A and D sustain individuals for 5–10 months and 2–4 months, respectively, while vitamin B deficiencies (except B12) manifest within days, and vitamin C deficiency emerges within weeks and can lead to death in 5–6 months. The recommended dietary allowance (RDA) for vitamin C is 75 mg/day for women and 90 mg/day for men, with a tolerable upper level set at 2 g/day due to gastrointestinal upset. Specific populations warranting attention regarding vitamin C status include patients with periodontal disease, smokers, pregnant and lactating women, and the elderly.
Why it matters
Provides clinical guidance on the metabolic necessity, deficiency risks, safe intake limits, and high-risk groups for vitamin C supplementation and nutrition.
Limits
This is a narrative review with no primary experimental data, quantitative meta-analysis, or described systematic search strategy. Quantitative requirement adjustments for specific high-risk populations are not reported in the abstract.
Cited by
- supports The Recommended Dietary Allowance (RDA) for vitamin C is 90 milligrams per day for healthy men and 75 milligrams per day for healthy women.