You can’t feed your scalp a green juice, so what exactly are detox shampoos and serums doing for the hair? Essentially, says Proudman, they balance the scalp. “Our scalp is 7% of the total skin on our body but it’s completely unique because it has 180,000 oil glands on it,” says Proudman, “which is the largest concentration on the body anywhere. It also has sweat glands, so it needs to be looked after like skin, which we wash every day.” If you aren’t keeping your scalp clean, then you may experience an imbalance. This is due to a natural yeast which lives on our scalp. “We usually don’t know it’s there,” says Proudman, “but if you allow sebum, natural oil, and sweat to build up, this yeast becomes overactive, which can cause inflammation, itching, and scaling.” In this case, it’s not about detoxing, but instead, rebalancing.