Vitamin C supplementation slightly improves physical activity levels and reduces cold incidence in men with marginal vitamin C status: a randomized controlled trial

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#adolescent #adult #ascorbic-acid #ascorbic-acid-deficiency #body-mass-index

Vitamin C supplementation slightly improves physical activity levels and reduces cold incidence in men with marginal vitamin C status: a randomized controlled trial

Johnston et al., 2014 | Nutrients | Rct

Citation

Johnston Carol S, Barkyoumb Gillean M, Schumacher Sara S. Vitamin C supplementation slightly improves physical activity levels and reduces cold incidence in men with marginal vitamin C status: a randomized controlled trial. Nutrients. 2014-Jul-09;6(7):2572-83. doi:10.3390/nu6072572

Abstract

The early indications of vitamin C deficiency are unremarkable (fatigue, malaise, depression) and may manifest as a reduced desire to be physically active; moreover, hypovitaminosis C may be associated with increased cold duration and severity. This study examined the impact of vitamin C on physical activity and respiratory tract infections during the peak of the cold season. Healthy non-smoking adult men (18-35 years; BMI < 34 kg/m2; plasma vitamin C < 45 µmol/L) received either 1000 mg of vitamin C daily (n = 15) or placebo (n = 13) in a randomized, double-blind, eight-week trial. All participants completed the Wisconsin Upper Respiratory Symptom Survey-21 daily and the Godin Leisure-Time Exercise Questionnaire weekly. In the final two weeks of the trial, the physical activity score rose modestly for the vitamin C group vs. placebo after adjusting for baseline values: +39.6% (95% CI [-4.5,83.7]; p = 0.10). The number of participants reporting cold episodes was 7 and 11 for the vitamin C and placebo groups respectively during the eight-week trial (RR = 0.55; 95% CI [0.33,0.94]; p = 0.04) and cold duration was reduced 59% in the vitamin C versus placebo groups (-3.2 days; 95% CI [-7.0,0.6]; p = 0.06). These data suggest measurable health advantages associated with vitamin C supplementation in a population with adequate-to-low vitamin C status.

Key Findings

These data suggest measurable health advantages associated with vitamin C supplementation in a population with adequate-to-low vitamin C status.

Outcomes Measured

  • depression

Population

Field Value
Population See abstract
Sample Size 15
Age Range 18-35 years
Condition depression

MeSH Terms

  • Adolescent
  • Adult
  • Ascorbic Acid
  • Ascorbic Acid Deficiency
  • Body Mass Index
  • Common Cold
  • Dietary Supplements
  • Double-Blind Method
  • Health Surveys
  • Healthy Volunteers
  • Humans
  • Incidence
  • Male
  • Motor Activity
  • Nutritional Status
  • Surveys and Questionnaires
  • Wisconsin
  • Young Adult

Evidence Classification

  • Level: Rct
  • Publication Types: Journal Article, Randomized Controlled Trial
  • Vertical: vitamin-c-immune

Provenance

Source extracted via PubMed E-utilities API on 2026-04-09