Red is Hot & Blue is Cool

In the late 1950s, the color researcher Robert Gerard took this a step further.

He noted that in human beings, both psychological and physical activity appear to increase as the wavelength of the light increases.

In other words, reds, oranges and yellows are just naturally more stimulating to us than greens, blues and purples.

He felt the color blue could be a supplementary therapy—for example as a tranquilizer and relaxant in anxious individuals and as a way of reducing blood pressure in the treatment of hypertension.

Later research tends to support his conclusions.

In an experiment where prisoners were randomly assigned to either red, yellow, blue or green wings, those in the blue and green wings were less inclined to violence than those in red and yellow wings.

Pink has also been found to have a tranquilizing and calming effect within minutes of exposure. It seems to suppress hostile, aggressive, and anxious behavior.

Further tests show that blood pressure, pulse, and respiration rates tend to increase most under yellow light, moderately under orange, and less under red. They decrease most under black, moderately under blue, and minimally under green.

Color also appears to affect our response to food.

For example, in fast food restaurants the décor is often designed around appetite-promoting colors, such as reds and oranges—a belief that also surfaces in traditional wisdom.


Traditional color wisdom—reaching as far back as ancient Egyptian times—offers similar conclusions, though based on a very different, non-scientific approach.

In classical Indian philosophy, for example, the seven colors of the rainbow are associated with the seven chakras (or energy centers) of the body.

Each chakra is related to a specific body function and has specific effects.