Quantitative risk-benefit assessment of fish and seafood consumption scenarios to support recommendations

Abstract Background Fish/seafood consumption has health benefits, namely due to its omega-3 fatty acids levels and risks due to methylmercury contamination. This study aims to quantify the health impact of hypothetical scenarios of fish/seafood consumption through a risk-benefit assessment and provide support for recommendations, using Portuguese food consumption data. Methods We used data from the National Food, Nutrition and Physical Activity Survey 2015-2016 (n = 5811) to estimate the mean exposure to methylmercury and EPA+DHA in the current and alternative scenarios. Alternative scenarios were modelled using probabilistic approaches to reflect substitutions from the current consumption in the type of fish/seafood (predatory vs low-mercury species) or its frequency (1-7x/week). The overall scenarios’ impact was quantified using Disability-Adjusted Life Years (DALYs). Results About 14% of the Portuguese population exceeds the methylmercury tolerable weekly intake, and this prevalence is higher among small children (36.6%). Nevertheless, if the fish/seafood consumption increased to once a day, ≈11450 DALYs could be prevented each year. However, such a scenario would result in higher risk for pregnant women (1398 extra DALYs). Moreover, excluding predatory species consumption resulted in small but significant health gains (-1078 DALYs). Conclusions For the general population, the maximum health gains are obtained by consuming fish/seafood up to 7x/week, but among children and pregnant women, the frequency should be limited to 3-5x/week. All population should preferably choose non-predatory species. Key messages Daily fish consumption results in the highest overall populational health gain, but children and pregnant women need to limit it to 3-5x/week, due to methylmercury exposure.