Mental Effects of a Fast Food Diet

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It is almost certain that if you eat a diet comprised of primarily fast food, you won't be functioning at your optimum capacity -- physically or mentally. Fast food consumption can cause an array of mental effects, ranging from depression to hyperactivity. It's not just one ingredient at fault, either. Fast food meals contain a toxic mixture of unhealthy fats, preservatives, coloring and refined carbohydrates that can create imbalances in your brain.


A fast food diet can cause depression for a number of reasons. The fats found in many fast foods are one culprit. Fast food often contains trans-fatty acids, which, besides clogging arteries, have been shown to cause depression, according to Dr. Almudena Sánchez-Villegas, who studied the diets of 12,000 people for six years. An imbalance of fatty acids may be another reason why people who eat fast food are more likely to become depressed. Ideally, people should consume a ratio of no greater than nine parts omega 6 fatty acids to one part omega 3 fatty acids. A typical order of french fries has a fatty acid ratio of 16 to 1, setting the stage for poor physical and mental health.


The lack of omega 3 fatty acids in fast foods can create a mental state that includes anxiety along with depression. This double-whammy is cause to re-evaluate your diet if you eat many fried foods. It's not just what fast food lacks that can cause anxiety, however. Fast food is high in refined carbohydrates, which can lead to blood sugar fluctuations. If your blood sugar dips into hypoglycemic levels, you can experience anxiety, trembling, confusion and fatigue.


Anxiety and depression aren't the only mental effects that fast food can induce. Eating a diet high in artificial colors and preservatives may play a role, as well. A review of related research published in "Clinical Pediatrics" indicates that many artificial colorings, along with the preservative sodium benzoate, increase hyperactivity. Although sugar has not definitively been shown to increase clinical hyperactivity, most people are familiar with the feeling of a "sugar rush," which can make you feel hyper, jittery or irritable.

Seemingly Healthy Choices

Fast food restaurants are beginning to address consumer's concerns about the food they eat, but often in a superficial manner. You may see what appears to be a healthier choice on the menu than the usual burger, fries and soft drinks, but this may not necessarily be the case. For example, the Apple Pecan Salad chicken salad at Wendy's contains 9 g of saturated fat and 39 g of sugar. Another seemingly healthy choice, the Fruit and Maple Oatmeal at McDonald's has 32 g of sugar. The Fruit 'n Yogurt Parfait has 21 g of sugar -- 3 g more than its ice cream cone. As with other refined carbohydrates, sugar rapidly raises blood glucose levels. This can affect memory and cause symptoms of hypoglycemia when your blood sugar levels subsequently take a dive. Your best bet is to prepare healthy low-sugar, high omega-3 meals at home, and avoid fast food altogether, whenever possible.