Shoppers have been eating more healthily as the mercury rises, new figures indicate.

According to NielsenIQ (NIQ) till roll data for the four weeks to 14 June, sales at UK supermarkets were up 3.8 per cent versus May. 

The analyst said the uplift in sales is likely due to warmer weather facilitating al fresco and at-home dining, as well as a sunny Father’s Day encouraging shoppers to celebrate with family.

However, it added that waning consumer confidence and continuing inflation means UK shoppers are still buying with caution, as unit growths were down 0.7 per cent.

A key trend identified by NIQ is a shift in shoppers’ diets towards healthier eating habits. The largest category shifts were big-pot yogurts (+29 per cent), followed by frozen fruit (+21 per cent), vitamins (+15 per cent) and healthier snacks such as rice cakes and sushi, which all saw an increase in sales over the past four weeks.

The figures come as findings from NIQ’s Global State of Health & Wellness report reveal that 66 per cent of UK shoppers are actively making choices to improve their health. Some 44 per cent of consumers are actively working to reduce their intake of processed items, while 36 per cent are making a concerted effort to eat five portions of fruits and vegetables each day.

Mike Watkins, head of retailer and business insight at NielsenIQ, said: “In the first six weeks of summer 2025, shoppers have spent £700m more and 75 per cent (£521m) of that has been in fresh and chilled foods. This perhaps indicates the shift of spend not just towards convenient fresh food options but towards a more healthy and nutritious diet.”