A double chin is a roll of fat below your chin, so that it looks like you have two chins. It may be caused by heredity, excess weight, or loss of skin elasticity due to aging. Treatments may include specific exercises, as well as lipolysis (a laser treatment) and injectables (Kybella).
Melasma is a patchy, facial skin discoloration caused by excessive UV exposure or hormonal changes, such as during pregnancy. (It is often called a “pregnancy mask.”) As with age spots, melasma poses no health risks and may be treated with bleach, IPL, chemical peels, dermabrasion or cryosurgery.