Commentaries on ‘Vitamin C for preventing and treating the common cold’ with responses from the review author

Abstract

These are commentaries on a Cochrane review, published in this issue of EBCH, first published as: Douglas RM, Hemilä H, Chalker E, Treacy B. Vitamin C for preventing and treating the common cold. Cochrane Database of Systematic Reviews 2007, Issue 3. Art. No.: CD000980. DOI: 10.1002/14651858.CD000980. pub3.Further information for this Cochrane review is available in this issue of EBCH in the accompanying EBCH Summary and Characteristics and Key Findings Tables. Copyright © 2008 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd. The Cochrane Collaboration

Bias against Vitamin C in Mainstream Medicine: Examples from Trials of Vitamin C for Infections

“…(1) Total No. of Episodes Total Citations from 1997-2020 (2) Constituent of the Placebo p for Testing Vitamin C Effect (2-t) [33] 249 109 Lactose 0.046 [34] (3) 11 Ludvigsson (1977) [51] (4) 1279 20 not stated (4) 0.016 Pitt (1979) [52] (5) 1219 31 citric acid 0.023 Anderson (1972) [53] (6) 1170 7 citric acid 0.001 Total excluding the Karlowski trial 3668 41 re-analysis [47] of the trial 29 (1) All four trials were randomized, double-blind, and placebo-controlled. (2) Web of Science search 2021-11-5.…”

“…Neither the recruits or drill instructors nor the physicians and corpsmen who treated the recruits were aware of which pill any individual recruit was taking" (p. 908). (6) Anderson trial [53]: Outcome: "Total number of days confined to house": decrease of 30% in vitamin C group. "Each bottle of tablets was assigned a code number derived from a computer-generated list of consecutive numbers, randomized in pairs .…”

“…Apple also reported that many researchers found that workers receiving vitamins had considerably lower rates of absenteeism, stayed in their jobs longer, and even scored higher on their merit ratings [204] (pp. [3][4][5][6][7][8][9][10].…”

“…Later randomized trials supported Pauling's conclusions. In 2013, in our Cochrane review on vitamin C and the common cold, we calculated that regular vitamin C supplementation of ≥0.2 g/d shortened the duration of viral respiratory tract infections in adults by 7.7% (p = 0.00018) and in children by 14.2% (p = 0.000053) [4][5][6]. In five randomized trials with participants under heavy acute physical stress, vitamin C halved the incidence of common cold symptoms (p = 0.0000006) [4,7].…”

“…The goal of this paper is to demonstrate the bias against vitamin C by using examples primarily from the trials on vitamin C for infections. Some reviews and studies on vitamin C and respiratory infections [10][11][12][13][14][15] have been flawed [16][17][18][19][20][21][22][23], but this paper does not systematically review the effect of vitamin C on infections, since this is covered in other publications [4][5][6][7][8][9][24][25][26][27][28][29][30][31][32].…”