In this article. Body dysmorphic disorder (BDD) is a distinct mental disorder in which a person has symptoms of a medical illness, but the symptoms cannot be fully explained by an actual physical disorder. People with BDD are preoccupied with an imagined physical defect or a minor defect that others often cannot see.DD is a chronic (long-term) disorder that affects men and women equally. It usually begins during the teen years or early adulthood. The most common areas of concern for people with BDD include: 1  Skin imperfections: These include wrinkles, scars, acne, and blemishes.
Four standard time zones for the continental United States were introduced at noon on November 18, 1883, when the telegraph lines transmitted time signals to all major cities.
2 United States time zones 2.1 Standard time and daylight saving time. 2.2 Zones used in the contiguous U.S. 2.3 Zones used in states beyond the contiguous U.S. 2.4 Zones outside the states. 2.5 Minor Outlying Islands. 2.6 Antarctic research stations.