Chances are, if you think diet is responsible for changes in behavior, it probably is. A number of researchers have studied this issue in depth and have found that a definite link exists between junk food and behavior, particularly hyperactivity.
Preservatives
By definition, junk food is not fresh. Manufactured to have a shelf life of several months, many types of junk food have added preservatives. One example is sodium benzoate, used to preserve soft drinks. This preservative has been linked to increased hyperactivity in people who consume products that contain it. Children, whose brains are in a stage of rapid development, are especially vulnerable to the effects of food additives. Laura J. Stevens, MS, in a research review published in "Clinical Pediatrics," notes that in three separate studies, 70 to 79 percent of children already diagnosed with hyperactivity reacted to artificial colors and preservatives. To avoid preservatives in your diet or that of your child's, purchase fresh food that is not designed to have a lengthy shelf life.
Artificial Coloring
Junk food often comes in colors that you would never find in nature. These artifical colors, as noted by Stevens, can exact a toll on mental well-being and behavior. The FDA has concluded that artificial colorings might contribute to ADHD in some children. Experts are unsure whether children who already have ADHD are likely to react negatively to artificial coloring in foods or if the artificial colors themselves are the cause of ADHD. Harvard University researchers predict that removing these ingredients from the diet of a child with ADHD could be as much as half as effective as treating the child with the ADHD drug Ritalin.
Sugar
Most junk food consists of refined carbohydrates. Pastries, highly processed cereals, chips and sodas are just a few examples. Once eaten, these foods immediately affect blood sugar levels. Rising blood glucose levels can trigger the release of adrenaline, which can cause changes in the behavior of both adults and children. This phenomena is likely responsible for the term "sugar rush" that is used when someone feels excited or hyperactive after eating these foods.
Sugar consumption doesn't only affect children. When junk food consumer Dan White was charged with murdering the mayor of San Francisco and his supervisor, his lawyer successfully got the charges reduced to manslaughter, as Mr. White was deemed insane as a result of eating too much sugar prior to the deed -- a legal technique that is now called "The Twinkie Defense."
Lack of Micronutrients
An indirect manner in which junk food can influence behavior is by what it doesn't provide -- namely, a wide variety of vitamins and minerals. Children with ADHD, in particular, tend to have deficiencies in iron, magnesium, zinc and vitamin B6, according to the Harvard Medical School. Anecdotal evidence suggests that when people replace junk food with fruits and vegetables, mental and physical health can both show improvements.
References
- University of Texas; Insurance Insights; September 2008
- Harvard Medical School; FDA Panel Finds No Link Between Artificial Food Colorings and Hyperactivity in Most Children; Michael Craig Miller; April 2011
- "Clinical Pediatrics"; Dietary Sensitivities and ADHD Symptoms -- Thirty-five Years of Research; Laura Stevens, et al.; 2010
- University of Maryland Medical Center: Hyperactivity and Sugar -- Side Effects
- Harvard Medical School: Diet and Attention Deficit Hyperactivity Disorder
- Cornell University Law School: Twinkie Defense
