Ear hair canal is sometimes trimmed for cosmetic reasons. Excessive hair growth within or on the ear is known medically as "auricular hypertrichosis". Some men, particularly in the male population of India, have coarse hair growth along the lower portion of the helix, a condition referred to as "having "hairy pinnae"" ("hypertrichosis lanuginosa acquisita"). Hair is a protein filament that grows from follicles in the dermis, or skin. With the exception of areas of glabrous skin, the human body is covered in follicles which produce thick terminal and fine vellus hair. It is an important biomaterial primarily composed of protein, notably keratin.
Hair care can find sources of biotin in cereal-grain products, liver, egg yolk, soy flour, and yeast. Nuts contain high sources of selenium and therefore are important for a healthy scalp. Alpha-linolenic acid and zinc are also found in some nuts and help condition the hair and prevent hair shedding that can be caused by a lack of zinc. Protein deficiencies or low-quality protein can produce weak and brittle hair, and can eventually result in loss of hair color. Dairy products are good sources of calcium, a key component for hair growth. A balanced diet is extremely necessary for a healthy scalp