Food preferences A worldwide shared newsletter

Genetic and environmental influences both play a role in food preferences in adolescence
The formation of food preferences in children and adolescents is a complex process with
both genetic and environmental factors at play. This edition of The Global Fruit and Veg
Newsletter offers three viewpoints examining the role of genetics in shaping food preferences
and obesity in adolescents and children.
Joanne Cecil provides a summary of the connections between genotype and behavioural
phenotype in the maintenance of child energy balance and obesity. She reports that individual
genetic differences exist in susceptibility and resistance towards weight gain and obesity.
Individual genetic variations include common gene polymorphisms (such as variance to
the fat mass and obesity-associated (FTO) gene), and the rarer, single gene mutations that
lead to monogenic obesities. The former predisposes children towards obesogenic eating
behaviours via changes to the appetite pathways. While the latter lead to extreme obesity
in children, and appear to disrupt appetite regulating mechanisms that control food intake,
thus changing the energy balance.
Andrea Smith and Claire Llewellyn discuss the how preferences for different foods are
shaped by both genetic and environmental factors, providing data showing that even twins
have differing food preferences. One example, a 2016 twin study, showed that 54% of
variance of preferences for vegetable consumption could be explained by genetics at 18-
19 years. This is the largest amount of preferences explained by genetic influences, with
other foods having lower genetic influences in preference formation – for example starch
preferences are only 32% explained by genetic influences in 18-19 year olds. This variance
in preferences may not only be due to differences in genetics. The food environment of
various products also differs considerably, with different foods being advertised differently,
having different consumption opportunities, and different cultural consumption norms.
The role of the parent in creating a positive environment for healthy eating preferences
in children and adolescences is also well established. Marion Hetherington in her article
discusses the role of the parent in promoting vegetables to children via complementary
feeding. She gives the example of adding vegetable flavours to milk or baby rice. This
resulted in greater liking and intake of vegetables, thus setting up healthy eating preferences
at an earlier age.
The evidence suggests that when it comes to obesity and food preferences in children and
adolescents, genetics does play a role. However environmental factors are also vital, and
– to a larger extent – within our control. We can alter many environmental factors to create
healthier consumption preferences, such as changes in food advertising, food consumption
opportunities and norms. Altering the food environment is a positive not just for children
and adolescents, but for the wider population. Currently, being overweight is “normal” in
England with 61.7% of adults either overweight or obese. Changes to environmental factors
– including increased fruit and vegetable consumption – will help reduce this worrying
statistic, and keep it lower.