Breakfast, glycaemic index and health in young people

The often cited phrase “breakfast is the most important meal of the day” may have been largely anecdotal and lacking empirical evidence originally, particularly where children and adolescents (young people) are concerned. However, there is now a large body of evidence demonstrating that regular breakfast consumption is associated with a variety of nutritional and lifestyle-related health outcomes in large diverse samples of young people, which may prevent weight gain, nutrient deficiency and reduce risk factors for chronic disease. This evidence has been reviewed previously, but the link between breakfast composition and health has received less attention. There is emerging evidence in young people that suggests certain breakfasts are particularly beneficial for health, with much of this evidence focusing on ready-to-eat cereals and breakfast glycaemic index (GI). Substituting a high GI (HGI) breakfast for a low GI (LGI) breakfast may be particularly beneficial for overweight young people through increased glycaemic control and satiety. Thus, the purpose of this paper is to extend previous reviews on breakfast consumption and health to provide a greater understanding of the role of breakfast composition, particularly breakfast GI. Unlike the evidence on breakfast consumption, which has often been based on large cross-sectional studies, the evidence on breakfast GI is based primarily on controlled experimental studies, often with relatively small samples. At times, it was necessary to refer to the adult-based literature in this review to support findings from young people or to highlight areas that are particularly lacking in empirical evidence in this population. Since breakfast consumption has declined in young people and also decreases from childhood to adolescence, strategies to promote regular consumption of a healthy breakfast in young people are warranted. Future research in young people should place greater emphasis on breakfast composition, consider the mechanisms controlling relationships between breakfast consumption and health, and investigate the benefits of habitual consumption of LGI compared with HGI breakfasts.