Or how can we use science to determine whether consuming a certain amount of food is good or bad for us? The risk-benefit assessment, briefly described here, is a methodology that nutritionists will increasingly need to use and understand better in the future.
Beyond the essential role that food plays in maintaining human life, it is recognized that adequate food intake and the intake of its constituents can provide protection against certain diseases or, conversely, can be associated with adverse effects on human health. This situation is particularly relevant when potential positive and negative effects can occur simultaneously in the same food or constituent. An example that illustrates this situation is the case of oily fish, whose consumption is, on the one hand, associated with benefits to cardiovascular health due to adequate intake of essential n-3 fatty acids and, on the other hand, with risks to cognitive development in children due to contamination of the fish with methylmercury (MeHg).
Traditionally, risk and benefit assessments associated with food and/or nutrients were carried out in independent, unrelated processes, hindering the integrated interpretation of results both by policymakers, who contribute to establishing recommendations for the population, and by consumers in defining their food choices. A relatively recent alternative is the risk-benefit assessment of food.
How is risk-benefit assessment defined?
Risk-benefit assessment is an integrated and multidisciplinary methodology that aims to estimate the health impact of food intake, simultaneously accounting for the risks and benefits associated with the consumption of a particular food and its components. This methodology integrates concepts from various disciplines, including toxicology (i.e., risks associated with chemical contaminants, additives, etc.), microbiology (i.e., risks associated with pathogenic biological agents), and nutrition (i.e., benefits associated with macro and micronutrients and other compounds of nutritional interest), and, through the use of comparable quantitative or qualitative metrics, allows for an integrated balance of all risks and benefits.
Beyond the classic example of fish, other case studies have been evaluated using this methodology. For example, a 2017 study by Eneroth et al. assessed the impact of increasing nut consumption on the health of the Swedish population, from an average of 5 g/day to 30 g/day, simultaneously considering the risk of developing liver cancer, associated with increased exposure to Aflatoxin B1, and the benefit in terms of cardiovascular disease (CVD) prevention, associated with increased intake of n-3 fatty acids. The health impact was estimated by calculating the disease burden, expressed as disability - ), which combines the estimate of years of life lost due to premature death and years of life lived with illness and/or disability. The results obtained in this study indicate that increasing nut consumption to 30 g/day would prevent more than 7,000 cases of CVD, despite potentially inducing up to 3 additional cases of liver cancer, in the Swedish population in 2013. Considering the balance of risks and benefits, the assessment carried out allowed us to determine the health impact of increased nut consumption, estimating that this increase would allow a gain of approximately 77,000 years of healthy life in the Swedish population.
What are the main difficulties with this methodology?
There are several challenges that can hinder and/or compromise this type of assessment, namely the scarcity/quality of available data, interindividual variability regarding susceptibility to risks and benefits associated with food consumption, uncertainty about the plausibility and strength of evidence of epidemiological associations between foods/components and health effects, among other challenges. Each case study should be carefully evaluated and the feasibility of each assessment determined. Nevertheless, risk-benefit assessment should be seen as a holistic approach that allows estimating the impact of food consumption on human health, integrating the various associated risks and benefits into its results. The use of food risk-benefit assessment can be useful as a decision-support tool for competent public entities in defining dietary and nutritional recommendations, as well as for nutritionists in their professional practice.
How do I learn this methodology?
In 2010, the European Food Safety Authority (EFSA) published guidelines for conducting risk-benefit assessments of food. These guidelines propose a progressive, step-by-step approach and discuss some specific aspects and potential limitations of this type of analysis. The document also includes two distinct examples to illustrate the application of the proposed approach to conducting risk-benefit assessments of food .
capacity-building project in risk-benefit assessment (RiskBenefit4EU) is currently underway, bringing together a multidisciplinary team from several European countries (Portugal, France, and Denmark). The project aims to establish a framework and equip Portuguese researchers and other professionals with the necessary skills to conduct risk-benefit assessments of food, through a case study related to the consumption of cereal-based products by children up to 3 years of age.
