It keeps hair looking and feeling fresh even after styling, while caffeine helps to stimulate hair growth and give it volume. If hair loss is a concern, it also contains hemisqualane, an alternative to silicone that helps strengthen hair long after you wash the shampoo out. “Most volumizing shampoos I’ve tried leave my hair feeling squeaky and dry, but this one somehow makes it feel fuller and softer at the same time,” says Tandon.