HEALTH
Ever noticed how a walnut looks very much like our brains? It even has two hemispheres. Well, it turns out that’s exactly what they are good for. Our brains — especially the brains of adolescents. That’s the finding from a new study from Spain, which suggests that taking a few walnuts three times a week is enough to boost attention and brain growth in secondary school students.
The study’s researchers from the Barcelona Institute for Global Health, the Institut d’Investigació Sanitària Pere Virgili (IISPV) and the Hospital del Mar Medical Research Institute, studied 700 children aged 11–16 and found cognitive development and psychological maturation improved in those who regularly ate the nuts. They also found a big difference in those diagnosed with ADHD, who were much more able to concentrate in class and were less hyperactive.
Students from 12 schools in Barcelona were randomly divided into two groups: a control group who didn’t get the nuts and an experimental group who received 30g packages of walnut kernels (about six whole walnuts) they were told to eat every day for six months.
The researchers found there were benefits even for those who only ate the walnuts 100 times over the six months.
Walnuts are high in alpha-linolenic fatty acid, a type of omega-3 fundamental to brain development — especially when children’s bodies are changing fast as they do when they’re growing.
“Adolescence is a time of great biological changes,” says principal investigator Dr Jordi Julvez from the IISPV. “Hormonal transformation occurs, which in turn is responsible for stimulating the synaptic growth of the frontal lobe — the part of our brain that enables neuropsychological maturation, that is, more complex emotional and cognitive functions. Neurons that are well nourished with this type of fatty acids will be able to grow and form new, stronger synapses.”
While previous studies have looked at the effect of nuts on human health, their role during such a critical stage of cognitive development in adolescence has never been examined.
Ariadna Pinar, a doctoral student from IISPV and first author of the study published in the journal eClinicalMedicine, notes, “Adolescence is a period of great brain development and complex behaviours that requires a significant amount of energy and nutrients. If boys and girls would . . . eat a handful of walnuts a day, or at least three times a week, they would notice many substantial improvements in cognitive abilities and it would help them face the challenges of adolescence and entering adulthood.”