How Clothing Can Help You Stay Cool in a Heatwave

White clothing is a common choice in summer because it reflects more sunlight than black clothing. Yet researchers say the answer is more complicated than colour alone. The body also produces heat, and clothing can either trap that heat or allow it to escape.

A study of Bedouin robes found similar heat exposure under black and white robes. The key was the loose fit: in windy, dry conditions, air can rise in the space between a loose robe and the skin, carrying heat away. If clothes are tight, however, white is generally the better option.

Fabric also matters. A breathable material lets heat and water vapour pass through. A wicking material actively moves sweat away from the skin. Cotton absorbs sweat but can dry slowly. Linen is very breathable but also dries slowly, while nylon and polyester are widely used in activewear because they wick moisture and dry quickly.

High humidity changes the picture. When the air already holds a lot of water vapour, sweat evaporates less easily. That is why loose, lightweight clothing can feel particularly useful on a humid day.