Households buying high volumes of sugary or diet soft drinks linked to low socio-economic status and less healthy food purchases

A new PHI|Lab study published in PLOS Medicine found that households purchasing high volumes of sugary or diet drinks are more likely to have lower socio-economic status, higher body mass index (BMI) and overall less healthy food purchases.

The study was led by PHI|Lab members Nicolas Berger and Laura Cornelsen who analysed data on food and beverage purchases from nearly 9,000 British households who regularly purchased drinks such as soft drinks, juice or alcoholic beverages in 2016. The study aimed to better understand whether households with obesity are effectively targeted by current policies aimed at specific foods and drinks, as well as what the key sources of energy and nutrients are for those households in order to generate new effective policies.

Using latent class analysis, this study identified seven different groups of households on the basis of their regular beverage purchasing behaviour. Each group of households was characterised by relatively higher purchases of one or two categories of beverages: Sugar Sweetened Beverages (SSBs), Diet beverages, Fruit juices and Milk-based drinks, Beer and Cider, Wine, Water and lastly a Diverse group who purchased moderate levels of many different beverages.

Most of the household sample were in the Diverse group (30%), another 18% of the households were in the groups purchasing mostly SSB or Wine respectively, while the Diet beverage group made up 16% of the households. Beer and Cider, Fruit and milk-based drinks, and Water made up 7%, 6% and 4% of households, respectively.

By looking at other characteristics of the households, the results showed that those in the Diverse group were more likely to have higher income, whereas lower social grade was more likely for households in the SSB, Diet beverage or Beer and Cider groups.

The proportion of households with overweight or obesity was the highest in the SSB and Diet beverage groups (66.8% and 72.5%, respectively). When looking at total food and beverage purchases, households in the SSB group obtained higher total energy than other groups in which a smaller proportion of energy was from fruits and vegetables, and a greater proportion of energy was from less healthy food and beverages, than other groups. For households in both SSB and Diet beverage groups, there was a tendency to purchase a high proportion of energy from sweet snacks (~18%).

These findings suggest that households purchasing mostly sugary or diet drinks are at a higher risk of obesity, and might additionally benefit from policies that target sweet snacks, as a way of reducing their excess energy intake – for example, by extending the UK Treasury Soft Drinks Industry Levy to sweet snacks.


Nicolas Berger, Steve Cummins, Alexander Allen, Richard Smith, Laura Cornelsen. Patterns of beverage purchases amongst British households: a latent class analysis. PLOS Medicine. DOI: 10.1371/journal.pmed.1003245