Approved research

Exploring the association between dietary variety and weight

Lay summary

In this project, we will explore the relationship between food variety, portion size selection, energy density, and weight. The aims are to: 1) Examine the association between dietary variety (the consumption of different foods across the diet) and weight (as indicated by body mass index; BMI) in the UK population 2) Examine the association between the perception of dietary variety (the individual's own rating of variety in their diet) and weight in the UK population 3) Determine how the portions that individuals tend to consume across the diet influences the relationship between dietary variety and weight 4) Determine how the energy density (calorie content) of eaten foods influences the relationship between dietary variety and weight According to recent figures, 2 in 3 people across the globe are overweight or obese. As being overweight or obese is known to increase the risk of developing serious health problems including diabetes and cancer, it is important that we understand how biological, individual and environmental factors contribute to the development of obesity in order to improve the success of preventative strategies. Consuming a variety of foods from different food groups across the diet is one factor that has been shown to increase the amount of food that people eat, as well as the portion sizes that people choose to consume. This means that variety may be useful to encourage greater intake of healthy foods. However, it also means that variety can encourage greater intake of calorific foods, contributing to an increase in overall energy intake. As such, variety has been associated with having increased body fatness and weight. Despite our understanding of the independent effects of variety, portion size, and energy balance on food consumption and weight, relatively little is known about the combined influence that they have. Using data from the UK Biobank, we will further explore this relationship to further our understanding of the effects of dietary variety on weight, and to help inform the development of better strategies to combat overweight and obesity in the population. The data analyses will begin at the end of 2019. Writing of manuscripts and the presentation of results will take place during 2020. We expect the results from the project to be published early 2021.