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Date: 02-Apr-1999 Name: ascorbic Database: Medline (Alles) <1966 to March 1999> Set Search Results --------------------------------------------------------------------------- 001 exp *ascorbic acid/tu 1097 002 limit 1 to review articles 59 003 limit 2 to yr=1985-1999 42 004 exp *common cold/ 946 005 3 and 4 2 006 from 5 keep 1-2 2 007 6 2 <1> Unique Identifier 97129600 Authors Hemila H. Institution Department of Public Health, University of Helsinki, Finland. Title Vitamin C supplementation and common cold symptoms: problems with inaccurate reviews. [Review] [69 refs] Source Nutrition. 12(11-12):804-9, 1996 Nov-Dec. Abbreviated Source Nutrition. 12(11-12):804-9, 1996 Nov-Dec. MeSH Subject Headings Adult Ascorbic Acid/ad [Administration & Dosage] *Ascorbic Acid/tu [Therapeutic Use] Child *Common Cold/dt [Drug Therapy] Common Cold/pc [Prevention & Control] Controlled Clinical Trials Human Nutrition Policy Support, Non-U.S. Gov't Abstract In 1971, Linus Pauling carried out a meta-analysis of four placebo-controlled trials and concluded that it was highly unlikely that the decrease in the "integrated morbidity of the common cold" in vitamin C groups was caused by chance alone (P < 0.00003). Studies carried out since then have consistently found that vitamin C (> or = 1 g/d) alleviates common cold symptoms, indicating that the vitamin does indeed have physiologic effects on colds. However, widespread conviction that the vitamin has no proven effects on the common cold still remains. Three of the most influential reviews drawing this conclusion are considered in the present article. Two of them are cited in the current edition of the RDA nutritional recommendations as evidence that vitamin C is ineffective against colds. In this article, these three reviews are shown to contain serious inaccuracies and shortcomings, making them unreliable sources on the topic. The second purpose is to suggest possible conceptual reasons for the persistent resistance to the notion that vitamin C might have effects on colds. Although placebo-controlled trials have shown that vitamin C does alleviate common cold symptoms, important questions still remain. [References: 69] Publication Type Journal Article. Review. Review, Tutorial. <2> Unique Identifier 92190136 Authors Hemila H. Institution Institute of Biotechnology, University of Helsinki, Finland. Title Vitamin C and the common cold. [Review] [124 refs] Source British Journal of Nutrition. 67(1):3-16, 1992 Jan. Abbreviated Source Br J Nutr. 67(1):3-16, 1992 Jan. Local Messages Aanwezig in Centrale Medische Bibliotheek, AMC MeSH Subject Headings Antioxidants/pk [Pharmacokinetics] Ascorbic Acid/pk [Pharmacokinetics] *Ascorbic Acid/tu [Therapeutic Use] Chemotaxis, Leukocyte/de [Drug Effects] Clinical Trials *Common Cold/pc [Prevention & Control] Dose-Response Relationship, Drug Histamine Antagonists/pd [Pharmacology] Human Neutrophils/ph [Physiology] Phagocytosis/de [Drug Effects] Time Factors Abstract The effect of vitamin C on the common cold has been the subject of several studies. These studies do not support a considerable decrease in the incidence of the common cold with supplemental vitamin C. However, vitamin C has consistently decreased the duration of cold episodes and the severity of symptoms. The benefits that have been observed in different studies show a large variation and, therefore, the clinical significance may not be clearly inferred from them. The biochemical explanation for the benefits may be based on the antioxidant property of vitamin C. In an infection, phagocytic leucocytes become activated and they produce oxidizing compounds which are released from the cell. By reacting with these oxidants, vitamin C may decrease the inflammatory effects caused by them. Scurvy, which is caused by a deficiency in vitamin C, is mostly attributed to the decreased synthesis of collagen. However, vitamin C also participates in several other reactions, such as the destruction of oxidizing substances. The common cold studies indicate that the amounts of vitamin C which safely protect from scurvy may still be too low to provide an efficient rate for other reactions, possibly antioxidant in nature, in infected people. [References: 124] Publication Type Journal Article. Review. Review, Academic.