13 Dec 2018 --- The average calorie content of a restaurant meal in the UK is 977 kcal, with meals offered by full-service restaurants delivering 268 kcal more than the average fast-food option, a University of Liverpool study has found. With 39 percent of UK adults eating out at least once a week – according to a UK Food Standards Agency 2016 report – the health focused spotlight on energy content may now require a shift from fast-food to sit-down restaurants chains.