248 International Journal of Sport Nutrition and Exercise Metabolism, 2011, 21, 248-261 © 2011 Human Kinetics, Inc. Nutrition Knowledge in Athletes: A Systematic Review Susan Heaney, Helen O’Connor, Scott Michael, Janelle Gifford, and Geraldine Naughton Context: Nutrition education aims to enhance knowledge and improve dietary intake in athletes. Understanding athletes’ nutrition knowledge and its infuence on dietary intake will inform nutrition-education programs in this population. Purpose: To systematically review the level of nutrition knowledge in athletes, benchmark this against nonathlete comparison groups, and determine the impact of nutrition knowledge on dietary intake. Methods: An extensive literature search from the earliest record to March 2010 using the terms nutrition knowledge or diet knowledge and athlete or sport was conducted. Included studies recruited able or physi- cally disabled, male or female, competitive (recreational or elite) athletes over the age of 13 yr. Quantitative assessment of knowledge and, if available, diet intake was required. Because of variability in the assessment of nutrition knowledge and dietary intake, meta-analysis was not conducted. Results: Twenty-nine studies (17 published before 2000) measuring nutrition knowledge (7 including a nonathlete comparison group) met inclusion criteria. Athletes’ knowledge was equal to or better than that of nonathletes but lower than comparison groups including nutrition students. When found statistically signifcant, knowledge was greater in females than males. A weak (r < .44), positive association between knowledge and dietary intake was reported in 5 of 9 studies assessing this. Common faws in articles included inadequate statistical reporting, instrument vali- dation, and benchmarking. Conclusion: The nutrition knowledge of athletes and its impact on their dietary intake is equivocal. There is a need for high-quality, contemporary research using validated tools to measure nutrition knowledge and its impact on dietary intake. Keywords: dietary, sport, nutrition understanding, diet behavior Heaney, O’Connor, and Michael are with the Discipline of Exer- cise and Sport Science, and Gifford, the School of Molecular Bioscience, University of Sydney, Sydney, Australia. Naughton is with the School of Exercise Science, Australian Catholic University, Melbourne, Australia. A strong evidence base supports optimal dietary strategies to enhance athletic performance (American College of Sports Medicine, American Dietetic Associa- tion, & Dietitians of Canada, 2000; American Dietetic Association, Dietitians of Canada, & American Col- lege of Sports Medicine, 2009). However, the diets of athletes are often reported to be nutritionally inadequate compared with sport nutrition and general population recommendations (Burke, Cox, Cummings, & Desbrow, 2001; Hassapidou, Valasiadou, Tzioumakis, & Vrantza, 2002; Jonnalagadda, Ziegler, & Nelson, 2004). Athlete nutrition-education programs usually aim to rectify dietary inadequacies and promote optimal health and athletic performance by furthering sound knowledge in general and sport-nutrition-specifc areas. Education may be delivered by a variety of providers including coaches and athletic trainers, sport dietitians, nutrition- ists, sport scientists, and medical practitioners. Athletes also obtain information from a variety of other sources including school or tertiary-education programs, books, sport-specifc magazines, the mass media, and, increas- ingly, the Internet (Burns, Schiller, Merrick, & Wolf, 2004; Jacobson, Sobonya, & Ransone, 2001; Parr, Porter, & Hodgson, 1984). Even at the elite level, nutrition- education programs for athletes may be predominantly coach driven and reactive, with depth and frequency of intervention infuenced by fnancial constraints (Zinn, Schofeld, & Wall, 2006). In contrast to education pro- grams in other areas of nutrition, evaluation of athlete nutrition-education programs is rarely reported (Abood, Black, & Birnbaum, 2004; Collison, Kuczmarski, & Vickery, 1996). Nutrition-education programs are often based on the premise that superior nutrition knowledge may translate into better dietary intake. The notion of translation of knowledge into practice was supported by results from a large community sample in the United Kingdom showing an association between nutrition knowledge and increased fruit and vegetable intake and reduced fat consumption (Wardle, Parmenter, & Waller, 2000). A similar trend has been found in other studies (Axelson & Brinberg, 1992). However, the link between nutrition knowledge and dietary intake is complex and may be infuenced by many other factors including taste and food preference and cultural, religious, and family beliefs. Furthermore, convenience and skill in shopping and food preparation, including label reading, can alter food intake (Nestle et al., 1998; Obayashi, Bianchi, & Song, 2003). The asso- ciation between nutrition knowledge and dietary intake SCHOLARLY REVIEWS