Grapefruit (Citrus paradisi) – In addition to its refreshing citrus aroma, grapefruit is a cooling and cleansing essential oil which is often used to treat acne. Grapefruit oil increases your skin’s pH level, which can be beneficial in the treatment of acne. Grapefruits are a hybrid fruit, combining sweet oranges with Indonesian pomelos. The carbohydrates, amino acids and fruit acids in grapefruit provide a source of natural moisturization and skin cleansing.