Diet and cognition

In 317 Korean children and adolescents (average age 11.8 ± 3.3 years), the influence diet has on cognitive function was investigated. Following a series of food frequency questionnaires and neurocognitive tests [including a quick 5 minute test called symbol digit mortalities (SDMT)] the standard deviation in reaction time was found to be significantly shorter in girls than in boys, and both verbal memory and SDMT percentile results for girls were significantly higher than for boys. These positive correlations also could be made between the following foods and nutrients with cognitive tests: vitamin B1 (digital span forwards tasks and SDMT); vitamin B6 (digit span forward tests); nuts (SDMT); mushrooms (visual memory, reasoning); caffeine (reaction time) and snacks (reaction time). Lower omission errors were linked to intake of rice with mixed grains, eggs, protein, vitamins B1, B6, D, niacin and zinc. As for negative correlations, noodles were associated with lower scores in verbal memory, SDMT, shift attention and reason test results (p<0.05), Coca-cola was associated with decreased verbal memory results, fast food with lower SDMT and reasoning, and finally omission results were positively associated with eating rice and ramyeon (Korean ramen dish). Standard deviations in reaction times were positively correlated with consumption of rice, snacks, and chocolate. The findings suggest that even in children and adolescents in Korea, diet is closely related to cognitive function and proves to be an important consideration factor in the minds of parents. [NPID: cognition, children, Korea, adolescents, neurocognitive tests, verbal memory, cognitive tests, vitamin B1, vitamin B6, nuts, mushrooms, visual memory, reasoning, caffeine, reaction time, snacks, eggs, protein, soda, noodles, memory, ramen]

This is a 2016 systematic review on whether the consumption of a healthier diet influences children’s and adolescents’ executive functioning. Examined were studies of executive functioning among children or adolescents aged 6-18 years which also assessed food quality, macronutrients and/or foods. Following a search on several large databases, a total of 12 studies were found to meet the inclusion criteria. Among the twelve studies that looked at food quality or macronutrient intakes, those testing long-term effects of diet supported a link between healthier overall diet quality with improved executive functioning. Research that evaluated diet’s acute impact suggested that higher diet quality is related with executive functioning enhancements, but results were inconsistent. When considering the studies that solely inspected the influence of different foods, there was another positive association identified between healthier foods (e.g. whole grains, fish, fruits and/or vegetables) and executive function. On the other hand, less healthy foods, sugar-sweetened beverages, and red or processed meats were shown to correlate negatively with executive functioning. In summary, the overall evidence gathered by this systematic review suggests a positive relationship between healthier diet intake and executive functioning. [NPID: cognition, children, adolescence, executive functioning, prefrontal cortex, food quality, macronutrients, whole grains, fish, fruit, vegetables, FV intake, sugar-sweetened beverages]

Henriksson et. al (2017) explore the associations of nutrition with components of executive functioning, a set of important cognitive processes, in adolescence, beginning with this study investigating the relationship between dietary patterns and macronutrient composition with attention capacity in European adolescents. This study included 384 (165 male, 219 female) adolescents aged between 12.5 and 17.5 from 5 European countries in the Healthy Lifestyle in Europe by Nutrition in Adolescence study. Through the use of 2 non-consecutive 24hour recalls with a computer-based self-administered tool, three dietary patterns (dietary quality index, ideal diet score and Mediterranean diet score) and macronutrient/fibre intake could be determined. The d2 Test of Attention was utilised to gauge the participants’ attention capacity. In the adjusted regression analyses, it was found that higher diet quality index for adolescents and ideal diet score were associated with greater attention capacity (standardised β=0·16, P=0·002 and β=0·15, P=0·005, respectively). While Mediterranean score and macronutrient/fibre intake both could not be associated with attention capacity, the overall results suggest that healthier dietary patterns were correlated to increased attention capacity in adolescents. Following the findings of this study, intervention design studies may be warranted exploring a causal relationship between diet quality and attention. [NPID: cognition, executive functioning, executive function, prefrontal cortex, adolescence, macronutrients, attention, Europe, diet quality, Med diet, Mediterranean diet, fiber, fibre]

This 2020 study selected children living in Guinea-Bissau at risk of undernutrition and provided them with a selection of food supplements or meals. This was a randomized controlled trial whereby the 1059 children aged between 15 months and 7 years were randomized to one of three dietary conditions. One of these conditions involved feeding the kids with NEWSUP, a new food supplement high in plant polyphenols, proteins, and omega 3 fatty acids, and which contains a wide variety and high fortification of micronutrients. The participants in this condition group were given servings containing the same number of calorie content five mornings a week for 23 weeks. Another supplement condition was the intake of a fortified blended food (FBF) used in nutrition programs, while the third option was a traditional rice breakfast (the control condition). Among children less than 4 years old, the NEWSUP supplement enhanced working memory compared to the control meal. NEWSUP also showed the ability to reduce hemoglobin concentration among children with anemia. In addition, individuals who took NEWSUP saw increased lean tissue secretion and their body mass index z score did not increase as much as subjects receiving the fortified blended food. Finally, the new food supplement increased cerebral blood flow compared with the control meal and the fortified blended meal in both age groups combined. In conclusion, supplementation for 23 weeks could improve executive function, brain health, and nutritional health in young vulnerable children living in low-income countries. [NPID: Supplements, micronutrients, children, infants, diet, nutrition, Africa, executive function, brain health]

This 2020 systematic review was conducted to compile evidence on the effects of blueberries and blueberry products on cognition and mood. Travica et al. examined various randomized controlled trials, including 9 studies that used freeze-dried blueberries, 2 studies that used whole blueberries, and one study that used a blueberry concentrate. Five of these trials recruited children, while other studies involved young adults and older people. Blueberry consumption and supplementation were both found to enhance measures of cognitive performance, especially short- and long-term memory and spatial memory. These results were observed at various doses of blueberries and for different consumption times. In one of the studies, blueberry products had positive effects on mood, compared with other groups. But the other 4 studies did not report improvements. There was low risk of bias across all studies. This review suggests that blueberries may provide cognitive benefits but at the same time, it should be noted that there are considerable differences between the studies analyzed in terms of design, dosages, and anthocyanin content. Future trials should be encouraged to use standardized blueberry interventions, consider using placebo formulations, and to use consistently implemented tools for cognitive assessment. [NPID: cognition, mood, supplements, blueberry, anthocyanin, memory, brain, review, flavonoid]

The main aim of this 2019 study was to analyze the interaction between fish consumption and cognitive school performance in children and adolescents. Fish is generally considered to be beneficial for health and cognitive development among youths. Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are fatty acids found in fish and are said to have facilitated the evolution of the human brain. They must be ingested within the diet, but the recommended consumption level has yet to be established. Lehner et al. therefore tested the association between fish intake and cognitive performance in 17,000 German children and adolescents. Eating 8 grams of fish every day was found to increase the probability of achieving better final grades in German and mathematics, when compared with consuming very little or no fish. Eating more fish appeared to also affect final grade scores positively in German. These relationships were not linear, with higher doses of fish tending to correlate with dips in cognitive performance. These results support the previous reports of a positive association between fish intake and school performance. The U-shaped relationship suggests that mercury or other pollutants present in the fish may have detrimental effects at high intake levels. Since only half of the participants met the minimum fish consumption recommendations, eating fish should be promoted more aggressively in children. [NPID: brain development, children, fish, diet, cognition, cognitive performance, school, school grades, fatty acids]

This 2017 review evaluated the effect of micronutrient interventions on cognition by examining a wide variety of relevant randomized controlled trials. Only trials that looked at the impact of micronutrients on cognitive performance or academic performance among children aged 4-18 years were included. There were 19 trials that met the inclusion criteria, including studies conducted in developing and developed countries, and trials that examined both single and multiple micronutrient interventions. The cognitive domains assessed included fluid intelligence, crystallized intelligence, short-term memory, long-term memory, cognitive processing speed, attention and concentration, and school performance. Eight out of ten trials measuring fluid intelligence showed that micronutrient supplementation provided significant benefits to children who were deficient in micronutrients, especially in iron or iodine at baseline. The impact of micronutrient interventions on other cognitive domains were inconsistent. To conclude, there were consistent reports of improvements in fluid intelligence among micronutrient-deficient children after undergoing micronutrient interventions. Additional research is needed to confirm the benefits of micronutrient interventions on other cognitive domains and its effect on healthy subjects. [NPID: micronutrients, intervention, cognition, review, nutrients, nutrition, deficiencies, intelligence, academic performance, children]

hippocampus, the function of which is influenced by various health factors including diet. In fact, rodent studies have shown that diets high in saturated fats and sugars can impair hippocampal-dependent cognitive tasks. This present study by Hassevoort et al. assessed the relationship between several diet quality markers such as lipids, simple carbohydrates, and fiber with creativity in preadolescent children. With the help of the parents, the 57 child participants completed 3-day food records, underwent dual energy x-ray absorptiometry (assessment for central adiposity), and were tested on their VO2max to examine their aerobic fitness. In addition, the Verbal Form of the Torrance Test of Creative Thinking (TTCT) was used to evaluate the kids’ creativity levels. Lower creativity scores were linked with higher added sugar intake. Whereas higher fiber consumption was correlated with better creativity scores. These associations remained even after controlling for key covariates. This study represents one of the first reports of a connection between added sugar consumption and hippocampal-dependent cognition during childhood. Since the hippocampus plays an important role in creative thinking, learning and memory, these findings have potential educational and public health implications. [NPID: creativity, hippocampus, memory, learning, diet, nutrition, sugars, fats, fiber, diet quality]

In this 2017 study, Korean children and adolescents were tested on their cognitive function [assessing symbol digit modalities (SDMT), verbal memory, visual memory, shift attention, reasoning, and digit span], while their diets were also examined to discover how dietary consumption may affect cognitive ability. Considering standard deviation value, the girls’ reaction times were significantly shorter than that of the boys. Overall, the standard deviations in reaction times were positively associated with the consumption of snacks, rice, and chocolate, while increases in reaction times in general correlated with higher caffeine and snack intakes. Moreover, girls performed significantly better in terms of verbal memory and symbol digit modalities tests. Higher vitamin C, B1, and potassium intake was related with greater SDMT scores, while the eating of noodles was negatively associated with verbal memory, SDMT, shift attention, and reasoning test results. Furthermore, those participants who ate more fast food were more likely to perform worse in SDMT and reasoning tests. Drinking coca-cola was linked with poorer verbal performance also. However, mushroom intake showed positive correlation with visual memory and reasoning test results, while eating more nuts was connected with better SDMT results. While these results indicated a generally better relationship between dietary intake and cognitive function among the girls compared to the boys, the findings provide evidence that diet is strongly connected to cognitive function in healthy Korean children and adolescents. [NPID: cognition, Korea, symbol digit modalities, verbal memory, visual memory, shift attention, reasoning, digit span, cognitive ability, gender differences, gender, caffeine, snacking, snacks, rice, chocolate, vitamin C, B1, potassium, noodles, mushroom, verbal performance]