Omega-3 fatty acids are a family of polyunsaturated fats, including docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), and alpha-linolenic acid (ALA), although there are six in total.
In general, DHA and EPA are found in large quantities in oily fish and fish oils. Specialists from the Spanish Society of Dietetics and Food Sciences (SEDCA) point out that the foods richest in these fatty acids are salmon, mackerel, fresh tuna, herring, sardines, and anchovies.
Alpha-linolenic acid is present in foods of plant origin, especially in chia and flax seeds and in walnuts. Although to a lesser extent, it is also found in other nuts, seeds, and some legumes. “In the case of seeds, it is important to note that, for greater use and assimilation, they should be consumed ground, crushed, or soaked for at least one hour. This is because, if we consume them raw, we waste part of them. After all, they cannot be absorbed at the intestinal level,” point out the SEDCA experts.
Omega-3 fatty acids perform various functions in our body. “They are important components of the membranes surrounding every cell in the body. DHA concentrations are especially high in the retina, brain, and sperm.
Omega-3s also provide calories to give the body energy and have many functions in the heart, blood vessels, lungs, immune system, and endocrine system,” says the National Institutes of Health (NIH).
THE ATTENTION CAPACITY OF TEENAGERS
The contributions of omega-3 fatty acids to cardiovascular health, the regulation of blood lipids, and their antioxidant and anti-inflammatory role, among other benefits, were already known. But, in addition, a recent study conducted by ISGlobal and the Pere Virgili Health Research Institute has found that DHA is associated with a greater capacity for selective and sustained attention in adolescents, while alpha-linolenic acid is associated with less impulsiveness.
During adolescence, significant structural and functional changes occur in the brain, especially in the prefrontal area, which plays an important role in controlling attention. On the other hand, it is known that omega-3 fatty acids are essential for the proper development and functioning of the brain. The most abundant in the brain, particularly in the prefrontal area, is DHA, which is acquired through the consumption of fatty fish.
“Despite the well-known importance of DHA in brain development, few studies have evaluated whether it plays a role in the attention span of healthy adolescents,” comments Jordi Júlvez, coordinator of the study. “In addition, the possible role of alpha-linoleic acid, another omega-3, but of plant origin, has not been as widely studied,” he adds.
The aim of the study carried out by ISGlobal and the Pere Virgili Health Research Institute was to determine whether a higher consumption of DHA and alpha-linolenic acid was associated with a greater attention capacity in a group of 332 adolescents from different schools in Barcelona (northeast Spain).
To this end, participants underwent computerized tests that measured reaction times to determine the capacity for selective and sustained attention, the ability to inhibit distracting stimuli, and impulsivity. In addition, they answered a series of questions about dietary habits and gave blood samples to analyze their DHA and ALA levels.
The results showed that higher levels of DHA were associated with a greater capacity for selective and sustained attention, as well as a greater ability to inhibit distractions. In contrast, alpha-linolenic acid (ALA) was not associated with attention span but was associated with lower impulsivity.
“The role of ALA in attention is still unclear, but this finding may be clinically relevant, since impulsivity is a characteristic of several psychiatric disorders, such as ADHD (attention deficit hyperactivity disorder),” explains Ariadna Pinar-Martí, first author of the study.
“Our study indicates that dietary DHA most likely plays a role in tasks requiring attention, but further studies are needed to confirm a cause-effect relationship, particularly to understand the role of ALA,” Jordi Júlvez said.
However, the findings of this research add to existing evidence on the importance of consuming fatty fish, the main source of DHA, at a crucial stage of brain development, before reaching adulthood.