White paint does make a room appear both brighter and lighter, which makes the space appear bigger than it would if painted in darker shades. Other light colors can produce the same effect as white paint, including off-whites or creams, light gray, light yellows, light blue and other soft shades. Dark colors, such as black, brown and dark gray, on the other hand, make the room look smaller. When white paint is used on a ceiling, the ceiling appears higher than a darkly painted ceiling.
The reason that white and other light-colored paints provide the illusion of a taller or bigger room is due to the reflective properties of the paint. Both sunlight and artificial light bounce off light-colored ceilings and walls, which brightens the room, giving it a larger, more open appearance. Dark paints, on the other hand, absorb sunlight and artificial light, which darkens the room, giving it a smaller, more closed appearance.
When you paint a ceiling white, always choose a paint labeled for use on ceilings. These paints are generally made to be thicker than standard wall paints, which allows for application without dripping. If the ceiling has exposed beams, and you would like to enhance the white ceiling to make it appear even further away, creating the illusion of even greater height, consider painting the beams a dark color, which creates just that effect.
If the ceiling that you want to paint white already has a dark paint applied, you may have difficulty covering the darker color with the white paint unless you do some prep work. Use two coats of primer over a dark paint job to provide a good painting surface before attempting to apply the white paint to the dark surface, and use multiple coats of white paint to fully cover the darker color.