Act + Acre's Clarifying Hard Water Scalp and Hair Treatment for $38 detoxes your scalp from product buildup and hard water ...

Note: Dr. Loretta Pratt, a board-certified dermatologist at Advanced Dermatology PC, says Malassezia yeast thrives on sebum, which builds up on the scalp when you don't shampoo often enough.

Why Is Your Scalp So Oily? An oily scalp is often caused by an overproduction of sebum, your scalp’s natural oil. While sebum is essential for keeping your hair hydrated and protected ...