A new Spanish study published in the journal eClinicalMedicine, from the prestigious publisher The Lancet Discovery Science, reveals that consuming walnuts regularly may have a positive impact on the cognitive development and psychological maturation of adolescents. Walnuts are the only tree nut with a significant amount of alpha-linolenic acid (ALA), an omega-3 fatty acid essential for the body and which plays a key role in brain development, especially in the developmental stage. The results of this study, led by the Institut d’Investigació Sanitària Pere Virgili (IISPV), with the collaboration of ISGlobal and the Hospital del Mar Institute for Medical Research (IMIM), are promising as it is the first research that shows the importance of eating walnuts during adolescence.
This research demonstrates that a healthy, balanced diet that provides essential nutrients, such as those provided by walnuts, can have a beneficial effect on the cognitive and psychological development of adolescents. “Adolescence is a period of brain refinement, connectivity and complex behaviors, so it remains sensitive to a number of environmental and lifestyle factors, including diet, from which it requires a large amount of energy and nutrients for proper development. Walnuts are a nutrient-dense food and a rich plant-based source of ALA, an omega-3 fatty acid that provides energy and is essential for the body and its development. For this reason, walnuts are a great ally of adolescent health,” says Dr. Jordi Julvez, principal investigator and coordinator of the Neuro Èpia Research Group of the IISPV.
This study involved 700 volunteers, specifically, high school students between 11 and 16 years of age from 12 different high schools. The participants were randomly divided into two groups: the control group and the experimental group. The experimental group was given packets containing 30 grams of walnuts (equivalent to a handful) and were instructed to consume them daily for 6 months. Participants who consumed walnuts for at least 100 days showed improvements in attention functions and those with symptoms of attention deficit hyperactivity disorder (ADHD) had better behavior in class, paying more attention to the teacher and being less hyperactive. In addition, the study found an increase in functions
related to fluid intelligence, which is less influenced by learning and inherent to a person’s biology. Participants who followed more closely the recommended dose of walnuts and the number of days of consumption showed improvements in neuropsychological functions.
Adolescent Nutrition Habits in MENA Region
Over the last decade, the unhealthy lifestyle and poor dietary habits have been of great concern to the local health authorities in most Arab countries where obesity has reached an epidemic rate for both children and adults1. According to the results of the National Health Survey 2017–2018, the obesity rate amongst children and adolescents aged between 5 and 17 years reached about 17.35 per cent2. Apart from young people’s unhealthy food habits in UAE, they also tend to have irregular eating patterns, which may include skipping breakfast3. The diet of Arab adolescents is characterized by a low intake of fruit, vegetables, and milk and a high intake of sugar-sweetened beverages, fast foods, and sweets4.
To complement the encouraging results of this study, the research team will conduct a second observational trial to analyze the effects of walnut consumption during pregnancy, with emphasis on the cognitive development and psychological maturation of infants. In this way, the aim is to demonstrate the importance of following healthy eating habits from the first years of life.
The California Walnut Commission (CWC) supported this study by providing the necessary walnuts for the research, without intervening in the design or discussion of the study results.
Study reference:
- Pinar-Martí A, Gignac F, Fernández-Barrés S, Romaguera D, Sala-Vila A, Lázaro I, Ranzani OT, Persavento C, Delgado A, Carol A, Torrent J, Gonzalez J, Roso E, Barrera-Gómez J, López-Vicente M, Boucher O, Nieuwenhuijsen M, Turner MC, Burgaleta M, Canals J, Arija V, Basagaña X, Ros E, Salas-Salvadó J, Sunyer J, Julvez J. Effect of Walnut Consumption on Neuropsychological Development in Healthy Adolescents: A Multi-school Randomized Controlled Trial. April 06, 2023. doi: 10.1016/j.eclinm.2023.101954.
1 https://knepublishing.com/index.php/ajne/article/view/1226/2672
2 Children’s health – The Official Portal of the UAE Government
4 https://knepublishing.com/index.php/ajne/article/view/1226/2672
