Marks & Spencer has announced its take-out sandwiches will all contain extra vitamin D.

All the retail giant’s pre-packed sandwiches will have a minimum of 15% of the recommended daily intake of the vitamin.

Helen Seward, nutritionist at Marks & Spencer, said: “As the days get shorter and autumn arrives, it’s harder for our bodies to receive as much vitamin D as they require, due to the limited sunshine and the amount of time we spend outdoors.

“Vitamin D plays an extremely important part in a balanced diet and by adding it to something as simple as bread mean that customers don’t have change their usual diets.”

The retailer introduced a raised amount of vitamins to its pre-packed loaves of bread last year, while high street food-to-go outlets were criticised this month for selling unhealthy breakfast lines.