Early fish consumption may prevent preschool wheeze

According to a new Swedish study children who started eating fish before nine months of age are less likely to suffer from preschool wheeze.

The observational study analyzed children who had had three or more episodes of wheezing per year, based on responses from 4,171 randomly selected families, who answered questionnaires at the following periods: when their children were 6 months, 12 months, and 4.5 years of age (1). The study included children who did and did not use asthma medication (inhaled corticosteroid), comparing them with children who did not wheeze. The wheezy sample was further broken down into children who only developed episodic viral wheeze when they had colds and multiple trigger wheeze, where children also wheezed when they didn't have a cold but were reacting to factors such as allergens, tobacco smoke, or exercise. The analysis showed that eating fish before the age of 9 months almost halved the likelihood of suffering recurrent wheeze at
4.5 years. The fish most commonly eaten was white fish, followed by salmon and flat fish.

The researchers concluded that early fish consumption may have a protective effect against developing preschool wheeze. Fish, being rich in omega-3 fatty acids, has been suggested to oppose the action of omega-6 fatty acids, thereby reducing the risk of allergy (2). Other studies have reported that the preventative effect of fish on wheezing might be independent of the type of fish ingested, indicating that the effect cannot be ascribed to omega-3 fatty acids alone (3). Recurrent wheeze is a very common clinical problem in preschool children and there is a need for better medical treatment and improved understanding of the underlying mechanisms.

1. Goksör E. et al. Preschool wheeze – impact of early fish introduction and neonatal antibiotics. Acta Paediatrica. Published online November 2011.
   
   
2.  Kremmyda L. S. et al. Atopy risk in infants and children in relation to early exposure to fish, oily fish, or long-chain omega-3 fatty acids: a systematic review. Clin Rev Allergy Immunol. 2011; 41(1):36–66.
   
   
3. Øien T. et al. Do early intake of fish and fish oil protect against eczema and doctor-diagnosed asthma at 2 years of age? A cohort study. J Epidemiol Community Health. 2010; 64:124–129.