Vitamin C and the common cold

Vitamin C and the common cold [in Swedish] Ingvar Liljefors Läkartidningen 1972;69(28):3304-3305 PubMed record: 4558644 https://www.ncbi.nlm.nih.gov/pubmed/4558644 English translation of this paper was by Harri Hemilä [email protected] https://www.mv.helsinki.fi/home/hemila This report was translated for research on vitamin C and the common cold by Harri Hemilä and Elizabeth Chalker, eg. https://doi.org/10.1002/14651858.CD000980.pub4 https://www.ncbi.nlm.nih.gov/pmc/articles/pmc8078152 https://hdl.handle.net/10138/225864 The scanned Swedish text is at the end of this document. Abstract Docent INGVAR LILJEFORS, deputy chief physician at the St Görans hospital in Stockholm, has studied the prophylactic effects of vitamin C - ascorbic acid – in a four-week double-blind study with 40 participants of military repetition exercises. The active substance was given as a dose of 1 g × 2 for two weeks, and placebo for the remaining two weeks. Ten people became sick when on vitamin C, 9 when on placebo. Vitamin C has not been shown to have any prophylactic effects against the common cold. 1 Vitamin C and the common cold [in Swedish] Ingvar Liljefors Läkartidningen 1972;69(28):3304-3305 Introduction Among the preparations which are generally considered to potentially have prophylactic effect against virus diseases of the upper respiratory tract of the »common cold type», vitamin C -ascorbic acid – has a prominent role. A new book »Vitamin C and the Common Cold» by Nobel prize winner Linus Pauling gives further hope for those who try to avoid the irritating discomfort. However, many of the clinical studies that have been carried out to show the protective effects of vitamin C against the common cold are not indisputable (The Medical Letter 1970, 1971). Newsweek (1971) summarizes an experimental study in which high doses of vitamin C did not give protection against inoculated common cold virus. Since there seemed to be room for a further controlled study, this was done with the cooperation of Astra Läkemedel Co. Materials and Methods Among participants of military repetition exercises in Autumn 1971, 40 people were selected who were willing to be administered vitamin C as a prophylaxis for the common cold. Participants were aged between 27 and 56 yr (average age 36.5 yr). None of the participants had diabetes or tendency to urinary tract infection; no other medical treatments were used either. The participants were asked about upper respiratory tract infections of the common cold type over the previous year. None had a clinically evident infection at the beginning of the study. Preparation was an effervescent tablet and was administered 1 tablet in the morning and the evening. Treatment was administered for 4 weeks, starting at 5 days after the beginning of the repetition exercises. The study was carried out as a »double-blind cross-over trial» so that each participant received all the tablets for the treatment period, of which half were active substance and half were placebo, randomly divided between the first two and last two weeks. The amount of active substance was 1 g per tablet. Recording of symptoms for people who caught upper respiratory tract infections was done almost daily by the author. According to the degree of severity, the symptoms were divided to two groups: 1) Mild, catarrhal symptoms, symptomatic treatment; fit for military service. 2) Severe catarrhal symptoms with fever and general systemic symptoms, complications (otitis, pneumonia); not fit for military service. Recording of the symptoms was done for the first two weeks (period I). People who then became sick were withdrawn from the last two weeks (period II). 2 Results 16 people – 8 in each group – had had an upper respiratory tract infection of the common cold type during the preceding half year. During period I (see Table), 25 people were treated with vitamin C and 6 of them became sick, compared with 5 of the 15 participants who were treated with placebo. During period II, 3 participants dropped out, but of the remaining 26 who were not previously sick, 8 became sick and this was evenly divided between the groups A and B. In all, 10 became sick during the vitamin C treatment, and 9 became sick during the placebo treatment. No adverse effects related to the treatment could be observed. Discussion Of the earlier studies on the effect of vitamin C on the common cold some are old (Cowan oa 1942; Glazebrook, Thomson 1942) and some are less well controlled (Bessel-Lorck 1959; Ritzel 1961; Wilson, Loh 1969). This current study was done impartially with a group of individuals which could be expected to suffer from an epidemic of the common cold. Through daily contact by the author even relatively mild symptoms could be registered. Half of the people included in the study caught upper respiratory tract infections, though only 6 were of such kind to prevent military service. No protective effect of vitamin C could be traced. Table The number of people who became sick with and without treatment with vitamin C. Period I Period II Group A B A B Number at risk 25 15 18 8 Preparation Vitamin C Placebo Vitamin C Placebo Group 1 symptoms 4 4 2 3 Group 2 symptoms 2 1 2 1 Dropped out - - 1 2 References, see the Swedish version below 3