The top layer of hair is the most exposed to environmental agents, such as sun, wind, and pollution. So, it's the one that suffers the most wear and damage, ...

When your hair is dry, frizz can happen when it absorbs moisture from the environment. Even for healthy hair, high humidity environments can lead to frizz when ...

Hair in the top layer is more likely to be frizzy because it is the most exposed hair part to pollution, sunlight, humidity, and friction when we sleep. ... ...