Fiber is classified as soluble or insoluble. Soluble fiber dissolves in liquid. Insoluble fiber does not. Soluble fiber is important to the control of blood sugar levels because of its ability to slow the absorption of carbohydrates into the blood stream. Carbohydrates -- sugars and starches in food -- are turned into glucose. Glucose is the fuel of the brain and is required in large and steady amounts for mental acuity and learning. According to Paul E. Gold of the University of Illinois College of Medicine, "Glucose enhances learning and memory."
Studies on breakfast composition and academic performance indicate that students who skip breakfast or eat low-fiber foods score lower on tests of recall and recognition. Although fiber is not a source of glucose, soluble fiber increases the amount of time consumed foods remain in the stomach, leading to a steady supply of glucose to the brain. A constant supply of brain fuel increases students' concentration and auditory attention. Processed foods are typically lower in fiber than whole grains and other unprocessed foods. Breakfast choices should include high-fiber foods such as oats, whole wheat and fruits.
Students' lunches, like breakfast, aid in improved academic performance when high-fiber foods are included. By lunch time even high-fiber breakfast foods have been digested. It is time to replenish the body's supply of glucose-producing foods. Lunches that sustain high performance levels in students include a balance of three key components: high-fiber fruits and vegetables, protein and fats. This combination of foods provide the nutrients needed for energy and concentration.
Girls are more likely to experience a decrease in academic performance when a low-fiber breakfast or no breakfast is consumed. Age also appears to have an effect for female students, but not for males, with younger girls experiencing less impact from a low-fiber diet than older girls. Further research on gender differences in food response is needed at this time.