How often do I need to shampoo and how do I pick one that suits my hair?

The best solution is a Goldilocks approach: ‘Don’t overwash or underwash,’ says Dr Deeptej Singh. Photograph: Antonio Hugo Photo/Getty Images

Growing up, I washed my hair every day. I was washing my body every day, so I figured I should shampoo my hair daily too. Then, in my teens, a classmate with hair much thicker and more lustrous than mine told me shampoo was terrible – it strips your strands, she claimed, leaving your hair parched and fragile. Shampoo as little as possible, she advised. She herself only did it once a week.

I tried this for a couple of horrible months. All it accomplished was to make me look like something pulled out of a grease trap. I started washing my hair every other day, and have kept up that routine ever since.