Study investigated whether if a healthy lifestyle can lead to improved executive functions in adolescents. They found that improved overall nutrition led to a higher attention capacity.
Executive functions consist of sets of important cognitive functions that undergo a major developmental phase throughout adolescence. These “executive” cognitive processes include attentional control, inhibitory control, working memory, and cognitive flexibility, in addition to reasoning, problem-solving, and planning, and are essential for academic performance and physical and mental health. Attentional control is understood to be essential in any learning process, as it facilitates selective attention to particular stimuli while simultaneously inhibiting other distractions. During adolescence, modifiable factors that make a healthy lifestyle, such as diet and physical activity may promote cognitive development and attention capacity.
Previous research has suggested that dietary patterns may demonstrate a stronger association with executive functions than single nutrient/food intakes. Since similar implications may apply to the study of attention capacity, an article published in British Journal of Nutrition aimed to investigate the associations of dietary patterns and macronutrient composition with attention capacity in European adolescents.
The cross-sectional study examined 384 (165 male and 219 female) adolescent participants between the ages of 12.5 and 17.5 years from five European countries in the Healthy Lifestyle in Europe by Nutrition in Adolescence study. The d2 Test of Attention was administered in a classroom under the supervision of a fieldworker to examine attention capacity and response inhibition, and dietary intake was evaluated through two non-consecutive 24 hour recalls using a computer-based self-administered tool. Three dietary patterns were assessed: diet quality index considered quality, diversity, and equilibrium; ideal diet score (advocated by the American Heart Association) which is based on the DASH diet and has previously been linked to cognitive performance in children; and Mediterranean diet score, which has been correlated with cognition in older adults. Additionally, macronutrient and fibre intakes were calculated.
Data analysis indicated that a healthier diet pattern (higher diet quality index and ideal diet score) was associated with greater attention capacity in European adolescents. Interestingly, little evidence suggested that the Mediterranean diet score or macronutrient/fibre intake were correlated with attention capacity. In order to more comprehensively investigate these relationships, intervention studies evaluating a causal relationship between a healthy lifestyle, diet quality and attention capacity in adolescence are required.
Western diets rich in meat and refined sugars but poor in vegetables, fruits and fish have been associated with impaired cognitive function due to increased oxidative stress, neuroinflammation, and impaired blood-brain barrier integrity. Fruits and vegetables that contain high levels of neuroprotective polyphenols and micronutrients such as folate may be crucial for cognitive development. Brain-derived neurotrophic factor, which is vulnerable to changes in the diet, may also influence cognition, due to its involvement in the growth and survival of many types of neurons and synaptic plasticity. As well, insulin resistance and high blood pressure may negatively influence cognition.
There is a myriad of factors that influence cognition, attention and executive function. This study sheds some light on a healthy lifestyle, including nutrition as an important factor influencing executive function in adolescence. Improving overall nutrition is an important strategy to improve attention control in adolescents.
Written by Jordyn Posluns, B.Sc. (Hons)