Prevalence of hay fever and consumption of margarine in East Germany

Abstract

Authors' reply Sir—Ingo Witte, from the Margarine Institute for Healthy Diet, argues against a potential role for the consumption of margarine for the development of hay fever and atopy in East-German children by referring to decreasing sales of margarine in Germany in recent years (according to the National Bureau of Statistics, Berlin, Germany, by about 10% between 1991 and 1996 in eastern Germany). The GfK Panel Services started to collect data on the purchase of food per household in Eastern Germany only about 3 years after the fall of the Berlin wall in 1989, after which most western food products became rapidly available in East Germany. No information on fat consumption in former East Germany (GDR) can be obtained from this source. Other reports investigating earlier periods1Winkler G Brasche S Heinrich J Trends in food intake in adults from the city of Erfurt before and after the German reunification.Ann Nutr Metab. 1997; 41: 283-290Crossref PubMed Scopus (25) Google Scholar, 2Jaross W Bergmann S Wahrburg U Schulte H Assmann G DRECAN Team Dietary habits in Eastern Germany; changes after unification and their relation to CHD risk profiles (DRECAN).Rev Environ Health. 1996; 11: 27-32Crossref PubMed Scopus (7) Google Scholar suggest a striking increase in the consumption of margarine since 1989. For example, the results of repeated dietary surveys in random samples of adults in Erfurt, East Germany, in 1987–88 and 1991–92 show a significant increase in the mean daily intake of margarine (6 vs 40 g, p=0·0001 in men; 5 vs 22 g, p=0·0001 in women) and a concomittant significant reduction in the intake of butter (40 vs 17 g, p=0·0001 in men; 26 vs 13 g, p=0·0001 in women), as assessed by 3-day weighted dietary records. However, the interpretation of trends in consumption at the population level is of limited value for causal inference because of its potential for bias, known as ecological fallacy. Thus, the assessment of dietary intake on an individual level is clearly preferable.3Rothman KJ Greenland S Modern epidemiology. Lippincott-Raven, Philadelphia1998Google Scholar In our study, we asked parents about changes in the consumption of 22 different food items before and after unification of East and West Germany. Only changes in the intake of margarine and butter were significantly associated with hay fever or atopic sensitisation. This explorative approach has obvious limitations, which we acknowledge in the discussion of our findings. However, we feel that the hypothesis linking the intake of certain poly-unsaturated fatty acids, such as linoleic or linolenic acid, to the development of childhood atopy deserves further investigation because of its biological plausibility4Black PN Sharpe S Dietary fat and asthma: is there a connection?.Eur RespirJ. 1997; 10: 6-12Crossref PubMed Scopus (426) Google Scholar and supportive evidence from other studies.5Hodge L Salome CM Peat JK Haby MM Xuan W Woolcock AJ Consumption of oily fish and childhood asthma risk.Med J Aust. 1996; 164: 137-140PubMed Google Scholar Prevalence of hay fever and consumption of margarine in East GermanyErika von Mutius and colleagues (March 21, p 862)1 describe in their report of an increasing prevalence of hay fever and atopy among children in Leipzig, in former East Germany, a possible relation between the rise in hay fever and atopic symptoms and increased consumption of margarine in that country. Full-Text PDF