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Nutrition and cognition

By SCAN Registered Dieticians

The number of NCAA student-athletes has increased over the last decade to more than 460,000 men and women playing on 18,000 teams.1 Many educators and coaches agree that a student’s mood and ability to focus play significant roles in performance both in the classroom and on the playing field. Understanding the relationship between nutrition and cognition may help those who interact with student-athletes identify nutritional issues of most concern.

 Cognition is the act or process of knowing.2 This includes every mental process that may be described as an experience of knowing (including perceiving, recognizing, conceiving and reasoning), as differentiated from an experience of feeling or of willing. Simply, cognition is our ability to learn something new, process the information and remember it. For many years, researchers have studied the relationship between nutrition and cognition, looking specifically at the effects of certain nutrients or meals on brain function.


The nutrients

While it is important to focus on a total diet approach to meeting nutrition requirements, certain nutrients may play a larger role in brain function than others. One such macronutrient is carbohydrate. Unlike other organs, the energy requirement of the brain is met almost exclusively by glucose.3 In fact, the brain takes priority over working muscles when it comes to using carbohydrates for energy. For that reason, the DRI (daily recommended intake) recommends a minimum of 130 grams of carbohydrates per day just for proper brain function.4The energy stores in the brain are extremely small compared with its high rate of glucose use, necessitating a constant supply through the bloodstream.3 There is growing evidence that the provision of glucose may influence both memory and mood, particularly when intense metabolic demands are placed on the brain.3 Therefore, when menu planning, meal composition and timing as related to brain function and cognition should be considered in addition to the working muscles’ needs for carbohydrate.

A main micronutrient that affects brain function is iron. Even slightly lowered iron levels can cause fatigue, thinking impairments, and altered physical work capacity and productivity.5-7These and other symptoms associated with iron deficiency often resemble, and are subsequently mistaken for, symptoms of behavioral and learning problems. Although not completely understood, the most recent evidence points toward slowed central neural processing as a key component in the neural dysfunction exhibited in iron deficiency.7



Equally important as knowing which nutrients play a significant role in academic and athletic performance is the understanding of when these nutrients should be consumed to facilitate success for the student-athlete. When evaluating optimal meal timing, we should start by encouraging these nutrients be consumed with the first meal of the day.

Research indicates that breakfast is the most important meal of the day. Studies show that students who eat breakfast before school have better concentration, attention span and memory.8-10 On the contrary, a landmark study showed breakfast consumption declined between 1965 and 1991, with the most notable decline among older adolescents.11 Much less research has been done with the collegiate population; however, one can assume the downward trend continues into the collegiate years, especially with the additional commitment and responsibilities that collegiate student-athletes face. Supporting this is a recent study in which only 27 percent of female college athletes reported eating breakfast regularly.12

Evidence also supports the recommendation for mid-morning snacking. One study showed that children who ate a smaller breakfast, on average only 61 calories, spent significantly less time tending to their work than those who had eaten larger meals.13 The adverse effect was reversed by the consumption of a mid-morning snack. This should be emphasized to student-athletes as we encourage them to fuel early and often to support their high energy demands.


The take-home message

The most important aspect of proper fueling is to consume a variety of foods throughout the day and around training, as part of a total diet, or overall pattern of food consumption. Furthermore, evidence supports breakfast as the most important meal of the day, as well as healthy snacking. To help ensure all-day success, the breakfast meal should include a variety of nutrients, with a particular focus on carbohydrates and iron for enhanced cognition.


Written by SCAN Registered Dietitians (RDs). For advice on customizing a nutrition plan, consult a RD who specializes in sports, particularly a Board Certified Specialist in Sports Dietetics (CSSD). Find a SCAN RD at

©2013 Sports, Cardiovascular, and Wellness Nutrition (SCAN)



  1. “NCAA participation rates going up.” National Collegiate Athletic Association. Web. 2 Nov. 2011.
  2. “Cognition.” Merriam-Webster. Web. 2 Sept. 2013.
  3. Benton, D., and S. Nabb. “Carbohydrate, Memory,and Mood.” Nutrition Reviews 61.5 (2006):S61-S-67.
  4. Institute of Medicine. Dietary Reference Intakes for Energy, Carbohydrates, Fiber, Fat, Fatty Acids, Cholesterol, Protein and Amino Acids. Washington, D.C.: National Academy Press, 2005, print.
  5. Murray-Kolb, L. E., and J. L Beard. “Iron Treatment Normalizes Cognitive Function in Young Women.” American Journal of Clinical Nutrition 85 (2007):778-787.
  6. Verdon, F. et al. “Iron Supplementation for Unexplained Fatigue in Non-anaemic Women. Double Blind Randomized Placebo Controlled Trial.” British Medical Journal 326 (2003): 1-4.
  7. Beard, J. “Iron Deficiency Alters Brain Development and Functioning.” Journal of Nutrition133 (2003):1468S-1472S.
  8. Gajre, N. S. et al. “Breakfast Eating Habit and Its Influences on Attention-Concentration, Immediate Memory and School Achievement.” Indian Pediatrics. 45 (2008):824-828.
  9. Rampersaud G. C. et al. “Breakfast Habits, Nutritional Status, Body Weight and Academic Performance in Children and Adolescents.” Journal of the American Dietetic Association105.5 (2005):743-760.
  10. Widen-Muller, Katharina. et al. “Influence of Having Breakfast on Cognitive Performance and Mood in 13- to 20- Year-Old High School Students: Results of a Crossover Trial.” Pediatrics122 (2008):279-284.
  11. Affenito, S. “Breakfast: A Missed Opportunity. Journal of the American Dietetic Association107.54 (2007):565-569.
  12. Shriver, Lenka H., Nancy M. Betts, and Gena Wollenberg. “Dietary Intakes and Eating Habits of College Athletes: Are Female College Athletes Following the Current Sports Nutrition Standards.” Journal of American College Health 61.1 (2013):10-16.
  13. Benton, D. and M. Jarvis. “The Role of Breakfast and Mid-morning Snack on the Ability of Children to Concentrate at School. Physiology & Behavior 90.2-3 (2007):382-385.


Last Updated: Nov 12, 2013