Her negative reaction toward the color yellow may seem odd, but it really isn’t. The human eye can see 7 million colors. All these colors can affect a person’s mind and body. According to experts in fields ranging from interior decorating to psychology, color can alter moods, influence behavior, and even cause physical reactions — like raising blood pressure or suppressing appetite.

In addition to causing headaches, colors can make a person feel nauseated or tired. Bright lemon yellow is the most fatiguing of all colors. Why? The answer comes from the physics of light and optics. Bright colors reflect more light, and as a result they excessively stimulate the eyes If you look at yellow for too long your eyes may get irritated.

Research shows that babies cry more in yellow bedrooms, and families are more apt to fight in yellow kitchens.

But the news isn’t all bad for yellow. The color is known to promote confidence and learning. So while that yellow classroom may contribute to Ariella’s headaches, at the same time it might actually be helping her solve those challenging square root equations.

Other colors also have positive effects on people. For instance, blue helps the body relax, and orange tends to improve a person’s mood and appetite.

Think all of this is hogwash? The ancient Egyptians didn’t. Four thousand years ago, the Egyptians built healing temples of light, which filtered the sun’s rays and bathed patients in specific colors to treat particular illnesses and emotional states.

More recently, studies have shown that colors can affect you when you don’t see them. Noted neuropsychologist Kurt Goldstein confirmed in his classic, The Organism, that a blindfolded person will experience physiological reactions under rays of different colors. In other words, the skin reads color, and our bodies, minds, and emotions respond.

Exactly how does this happen? Attached to the human brain is the pineal gland, which controls the daily rhythms of life. When light enters through the eyes or skin, it travels along neurological pathways to this pineal gland. Different colors give off different wavelength frequencies, and these different frequencies have different effects on us.

It’s not by chance that McDonald’s restaurants executives chose a golden color for their arches, and that employee uniforms of many successful fast food chains are a combination of yellow, range, and red. These colors, with some of the longest wavelengths, are known to stimulate the appetite. In fact, years ago, when Burger King changed the color of its employee uniforms to blue and green — colors reputed to suppress the appetite — sales went down considerably.

Pink is another color that has proved to suppress the appetite and stop stress-related snacking. As part of a weight-control program at Johns Hopkins University in Baltimore, Maryland, patients are given a color square called bubble-gum pink to help them eat less. Even the National Institute of Mental Health has done studies showing that our mental health and behavior depend in part on having a normal balance of colors in our life.

Color is all around you — at work, in your home, in your wardrobe, and on your dinner plate. Many of these colors affect study habits, friendships, sleep patterns, and self-esteem. Picture the T-shirt or sweatshirt you like to wear most when you play sports. Imagine the rooms in which you feel most comfortable, nervous, or irritable. Think about foods or meals that turn you off. The colors in clothes, carpeting, or food may be influencing your moods.

Does this mean that you should carry color swatches with you to make sure you always benefit from the colors around you? No. Color is light energy that you can tap into simply by looking at or being around those that you need most at a given moment. “You can keep the right color energies around you by carefully selecting the foods you eat, the clothes you wear, and the places you park yourself,” says Emma Swedlow, an alternative healing practitioner in Baltimore, Maryland.“ Color really can be a wonderful tool for creating balance in your life. ”

Make color work for you: Color qualities, negative effects and practical uses.

Black: Promotes self-confidence, power, and strength. But, too much black can make a person feel depressed. Dress in black if you need to make a good impression — except when you’re trying to console a friend whose pet just died.

Violet Brings about a feeling of peacefulness and understanding; promotes sleep, suppresses appetite. But, too much violet can make a person feel disoriented. If you’re having trouble sleeping, place a purple bulb in your bedside table lamp. Turn the light on when you go to bed.

Blue: Calms the mind; gets rid of nervous tension; ...