The amount households are spending on food has fallen by 3.9% since 2010 despite rising prices, according to figures published on Thursday. The Department for Environment, Food and Rural Affairs report also found that Brits are eating less beef, cutting back on biscuits and chocolate, and drinking fewer alcoholic and fizzy drinks – although we are drinking more low-calorie soft drinks.

UK households are buying less food but spending more of their budget on it since prices rose in 2007, with those on the lowest incomes hardest hit, according to a new report.

On average, total expenditure on food and drink in 2013 was £42.18 per person per week. Households bought 6.1% less food in 2013 than in 2007. Across the board, consumers were often “trading down”, buying cheaper brands to save money. Food prices last year were about 12% higher in real terms than in 2007.

The Family Food 2013 report found an average 11.4% of all household spending went on food and non-alcoholic drink in 2013. For those on lower incomes, food and drink takes up a larger amount of household spending. For the lowest 20% by income, 16.5% was spent on food and drink, the largest expense after housing, power and fuel.

“Food is exerting greater pressure on household budgets since 2007 when food prices started to rise in real terms,” the report states. “Low income households bought less food in 2013 than in 2007”.

Statistics showed a clear short-term downward trend in purchases of meat, potatoes, vegetables, bread, beverages and alcoholic drinks.

Beef purchases, which account for half of raw-meat purchases, declined by 15.3% on 2010 sales. While households bought less fruit and vegetables over the same period, they spent more on them – 6.7% more on fresh and processed vegetables and 9.2% more on fresh and processed fruit.

Since 2007, there has been a 51% increase in the price of beef, a 53% increase in lamb and a 52% increase in pork. While the price of lamb fell slightly in 2013, meat prices overall continued to rise. The price of poultry has risen 28% since 2007, and fish by 41%.

The price of butter has risen by 67% over the same period, potatoes by 50%, other vegetables by 26%, fruit by 39% with fresh fruit rising 25%. The price of eggs, which had risen by 33% since 2007, fell slightly by 1.4% in 2013 with purchases showing a short-term upward trend.

The amount of food eaten out has been declining since 2001, with the largest decreases since 2010 in biscuits and chocolate, yoghurt and fromage frais, confectionery and alcoholic drinks, the report states.

People are not eating as healthily as the government would like, with average energy intake still about 5% higher than the recommended adult intake. Excluding table salt, the average intake of sodium is falling, but was still 79% above the recommended maximum of 2.4 grammes a day. The average adult is eating 14.4g of fibre a day, a fall of 5.4% on 2010, and less than the recommended 18g.

Soft drink purchases fell by 23% between 2010 and 2013, but there was an increase of 36% over the three years in low-calorie soft drinks.

Spending on all food and drink was highest in Northern Ireland at £47.16 per person per week and lowest in Wales at £37.59. Northern Ireland also saw the highest purchases of potatoes, 60% higher than the lowest in Scotland. Scotland demonstrates the highest weekly spend on alcohol of £3.64, with the lowest in Wales of £2.65. In England an average of 30% of all expenditure on food and drink went on eating out, rising to 34% in London. Scottish household’s bought less vegetables but more sandwiches, while Welsh households purchased the least ice cream, desserts, and cakes.