Slide Forehead Reduction (hairline lowering) A high or excessively large forehead can sometimes take away from your otherwise proportional features. A high forehead can be due to many different things ranging from genetic factors, hair loss, or prior surgeries. This can make patients feel very self-conscious and limit what hairstyles they are able to wear. Forehead reduction surgery, or lowering the hairline is a procedure that can be done to reduce a high hairline or large forehead in both men and women.