Children's Health Risk and Benefits of Fish Consumption: Risk Indices Based on a Diet Diary Follow-Up of Two Weeks

Abstract

Several epidemiological studies indicate that fish intake is associated with neurocognitive development and visual outcomes in children attributed to long-chain polyunsaturated fatty acids (PUFA). However, methylmercury (MeHg) represents the most toxic and abundant form of environmental mercury (Hg) exposure to humans and exposure occurs primarily through fish consumption. The objective of the study was to describe fish consumption during childhood in Portugal, estimating the intake of Hg from fish and calculating the indices of risk. The group consisted of 233 infants and students aged 7–11 yr and attending 5 primary schools in Lisbon, Amadora, and Sesimbra. Information regarding food consumption habits was collected through a food diary during 2 weeks, completed under the supervision of teachers and parents, where participants registered what was ingested for lunch and dinner during that period. The exposure assessment and indices of risk were calculated for each participant. Individuals were classified according to weekly intake and indices of risk determined per group. In addition, the methods used to collect information on fish intake habits, a food frequency questionnaire and diet diary, are described in relation to quality of information provided. The mean value of fish meals per week was approximately 5. The calculated indices of risk reached values above 1 in more than 50% of the studied population, demonstrating the presence of risk in subsets of the population. While Portuguese children represent an important group of fish consumers, this does not manifest as appreciable benefit with respect to omega-3 ingestion, as children ingest half or less of the recommended value (200 mg/d of omega-3), which is equivalent to being exposed to risk for Hg intoxication. The choice of fish species shows lack of knowledge of fish characteristics. Therefore, risk communication and population education need to be established to prevent consumption of predatory fish species that contribute to the increase in risk toxicity and to encourage ingestion of prey fish, which represent significant levels of high-value nutrients such as PUFA.