Since Tuesday, in all 24,000 American restaurants belonging to the Subway chain, it is now possible to eat sandwiches fortified with Vitamin D and calcium.

This 15 cm sandwich provides 30% of the recommended daily calcium intake and 20% for Vitamin D, i.e. the same amount found in a glass of milk.

Developed by Subway dieticians, the brand presents this sandwich as a way to combat calcium deficiency in Americans, indicated by statistics from the Center for Disease Control, or Vitamin D deficiency in older people. Research also shows a link between calcium deficiency and high blood pressure, whereas Vitamin D deficiency is linked to cardiovascular risks.

Putting the emphasis on the nutritional value of products offered is part of a general trend within the food service industry. McDonald's and Burger King, for example, have recently started offering oatmeal breakfasts.