Background Tackling the rise of non-communicable diseases has become a significant challenge for public health across the globe. Understanding diets and dietary behaviours is important due to significant links between poor diet and obesity, diabetes, cardio-vascular diseases and many cancers. This study aims to describe the patterns of expenditures on food and beverages purchased for at-home consumption in Great Britain and to examine socio-economic inequalities in the nutritional content of purchases.

Methods We use home-scan (Kantar Worldpanel) data covering daily purchases of all foods and beverages for at-home consumption in the period 2012–17 by ∼32,000 British households. The sample is nationally representative with respect to age and sex of the main shopper in the household, geographical region and socio-economic status. We estimate daily per capita purchases of energy, all sugars and saturated fats from 26 healthier and less healthy food groups defined using a nutrient profile model (UK Department of Health). Results are further stratified by social grade (A/B, C1/C2 and D/E).

Results Preliminary results show that daily per capita purchases of energy and sugar decreased between 2012 and 2017 from 2099 kcal (95% CI 2,091 to 2106 kcal) to 2002 kcal (95% CI 1,995 to 2009 kcal) and 116 g (95% CI 116 to 117 g) to 108 g (95% CI 108 to 109 g) respectively. Expenditure on saturated fat remained constant at 31 g (95% CI 31 to 32 g) per capita/day. Similar trends are observed across the three socio-economic groups.

We note a decline in energy purchased from meat and fish (8 kcal), bread and cereals (21 kcal), and fruits and vegetables (9 kcal), but an increase in the calories from dairy (7 kcal) and savoury snacks (9 kcal). There is a decrease in the energy and sugar purchased from less healthy non-alcoholic drinks, such that purchases of energy and sugar from healthier alternatives now exceed in comparison.

The nutritional content of sweet snacks expenditure has not changed (197 kcal and 18 g of sugar per capita/day). In contrast, the energy and sugar purchased from desserts and puddings decreased from 195 kcal (95% CI 194 to 196 kcal) to 166 kcal (95% CI 165 to 167 kcal), and from 20 g (95% CI 20 to 20 g) to 17 g (95% CI 16 to 17 g) respectively, accounting for 46% percent of the total decrease in sugar purchased daily.

Conclusion While small improvements in the nutritional content of food purchased for at-home consumption are detected, these may be offset by different trends in out-of-home purchases. To understand the extent to which these improvements influence social inequalities, further analyses focus on socio-economic differences in the nutritional content of purchases across all the food groups over time.