They support you. You need to support them. Wear shoes that fit. Poorly fitting shoes can cause bunions, corns, calluses, hammertoes and other foot problems. You can prevent some of these problems by paying attention to how you select your new shoes.
Sizes vary among shoe brands and styles.
Don't select shoes by the size marked inside the shoe. Judge the shoe by how it fits on your foot. Select a shoe that conforms as nearly as possible to the shape of your foot. Have your feet measured regularly. The size of your feet changes as you grow older.