Lavender essential oil is useful for hair care because it has been shown to be very effective on lice, lice eggs, and nits. Furthermore, lavender essential oil has also been shown to be very helpful in the treatment of hair loss, particularly for patients who suffer from alopecia, an autoimmune disease where the body rejects its own hair follicles. A Scottish study reported that more than 40% of alopecia patients in the study reported an increase in hair growth when they regularly rubbed lavender essential oil into their scalp. Therefore, lavender oil is sometimes recommended as a preventative measure for male pattern baldness.