Junk Food and Behavior

The importance of a healthy diet is often stressed, especially for young and developing kids. But is there more of a motive to eat healthy other than normal blood sugar levels and weight? I know it is common for kids to get a sudden burst of energy, or a “sugar rush”, after eating junk food but can it actually cause other serious behavioral problems?

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According to the “European Journal of Clinical Nutrition”, junk food can cause hyperactivity. A double-blind placebo controlled study was conducted in order to determine the effects of artificial food colorings and benzoate preservatives (x-variable) on the behaviors (y-variable) of a group of 1,837 four year olds. The children were put on a diet without any artificial colorings or benzoate preservatives for one week. After that week, some of the children got drinks containing the artificial coloring and preservatives while the others got the placebo mixture. Parents reported an increase in hyperactivity in the children that had gotten the artificial drinks while the others with the placebo drink observed no change. These observational results could be skewed because of the parents varied opinions and ratings of hyperactivity. This could also be a false-positive. The parents could be thinking that the kids are more hyper, but in reality they are not.

But is it possible that there was a more significant difference in energy of the kids who got the artificial drink just because of the fact that their bodies got used to not having these things? I think that this is definitely a possibility because their bodies had gotten used to NOT having bursts of energy due to the lack of these things, so when they finally had the drink containing artificial coloring, their bodies probably responded quickly and more severe.

In addition to hyperactivity, junk food can also have an effect on ones tendency to be violent according to the results of the Boston Youth Survey. This survey was given to students at 22 public high schools in Boston. 1,878 students were used in this observational study.

As shown in the Table 4 below provided by “Injury Prevention”, the independent variable was the consumption of soda and the dependent variable was the likelihood of violent acts. Each student was asked how much soda he/she had drank in the past seven days. 29.8% said they drank more than 5 cans of soda per week. For those who drank 5+ cans of soda per day; 40.3% carried a gun or knife, 56.7% were violent towards peers, 26.2% were violent in a relationship, and 42% were violent towards children in their family.

Overall, this study shows that people who drink more soda tend to have more violent and aggressive behaviors. Although the results show a correlation between the two, it does not mean that it is causal. As shown in Table 1, other variables were considered such as gender, race, BMI, hours of sleep, and alcohol and tobacco use. Yes, the amount of soda one drinks can effect the tendency towards violence but it does not directly cause it. Reverse causation is not a factor of this because being violent does not typically cause someone to eat more junk food.

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The results of this study are interesting because it is common that people who are lower on the socio-economic hierarchy tend to consume more junk food because it is more affordable. This is an article that discusses this theory. Those who are less wealthy tend to live in areas where crime is more common due to various reasons such as lack of interrelation with neighbors, insecurities, and an increased fear of crime. So, I think that these results could also largely be due to chance.

These studies support the theory that correlation does not necessarily mean causation. Although junk food can effect the behavior of a child, there can also be confounding variables that determine behavior. The confounding variables can be gender, socio-economic status, family orientation, or even the age of the mother at the time of birth. Junk food can effect a child’s hyperactivity, emotions, association with peers, and increased acts of violence, but these factors are not dependent on the amount of junk food a child consumes.








One thought on “Junk Food and Behavior

  1. Stephanie Michelle Friedman

    I think this is really well written blog post and is very interesting. I have heard a lot of things among increased sugar intake and more children being diagnosed with ADHD, I wonder if is a correlation? Another problem with junk food is the increase in childhood obesity in America, which is bad. Although sugar is good every once in a while I think it is causing problems in our society.

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