Why does the arch of your left foot itch?

An itchy arch of the left foot can be caused by several factors, including dry skin, fungal infections like athlete's foot, or allergic reactions to materials in shoes or socks. Other possibilities include irritations from sweat or friction, insect bites, or skin conditions such as eczema. If the itch persists or is accompanied by other symptoms, it's advisable to consult a healthcare professional for proper diagnosis and treatment.