A systematic review published in the journal Aggression and Violent Behavior describes the effectiveness of nutritional supplements in reducing excessive aggression in children and adolescents.
Study: Nutritional supplementation in the management of childhood/youth aggression: A systematic review. Image Credit: KonstantinChristian / Shutterstock
Background
Excessive aggressive behaviors in children and adolescents impair many aspects of life, including family, social, and academic activities. The long-term presence of severe aggression can lead to psychiatric disorders, including oppositional defiant disorder, conduct disorder, attention deficit hyperactivity disorder, autism spectrum disorder, and trauma-related disorders.
Neurochemical agents, such as serotonin, dopamine, oxytocin, GABA, and cortisol, can impact aggressive behaviors by modulating neuronal development and functioning. Psychosocial interventions are considered the first line of treatment for aggressive behaviors. Psychiatric medicines are only recommended if these interventions fail to control the behaviors.
Healthy development of the nervous system is required for adaptive aggression regulation, which in turn depends on the nutritional status of the body. Therefore, adequate intake of both macronutrients (carbohydrates, protein, and fat) and micronutrients (vitamins and minerals) is vital for the optimal development and functioning of the nervous system.
In the current systematic review, scientists have analyzed available evidence on the role of nutritional supplements in managing aggressive behaviors in children and adolescents.
Study design
The scientists conducted repeated screening of the studies collected from various scientific documentation databases. This led to the identification of 22 relevant studies that were included in the final analysis. The primary focus of these studies was on the effect of nutritional supplements in controlling violent or hetero-aggressive behaviors in individuals younger than 18 years of age.
Nutritional supplements were defined as any manufactured products containing micronutrients, macronutrients, or a combination of both. Regarding aggressive behaviors, the review's primary focus was on hetero-aggression, including both reactive and proactive aggression. Hetero-aggressive behavior is a type of aggression that is always directed toward other people or external things. This is the opposite to self-harm or auto-aggression.
Important observations
Among 22 studies selected for the analysis, 13 investigated the effect of macronutrients, six investigated micronutrients, and three investigated a combination of both macro and micronutrients. Moreover, single-nutrient supplementation was investigated in six studies, and multi-nutrient supplementation was investigated in 16 studies. The average period of supplementation was 14.8 weeks.
Effects of nutritional supplementation on hetero-aggression
Seven studies reported the beneficial effects of nutritional supplementation on aggressive behaviors of children and adolescents. In these studies, vitamins, minerals, omega-3 fatty acids, or a combination of these nutrients were used as supplements.
Eight studies reported no significant benefits of nutritional supplementation on hetero-aggression. In these studies, fish oil (eicosapentaenoic acid and docosahexaenoic acid), omega-3 fatty acids and essential fatty acids, vitamin D, or L-tryptophan were used for supplementation.
Mixed effects of nutritional supplementation were reported by seven studies. Vitamin B6, fatty acids and vitamins, omega-3 fatty acids, or carnitine were used as supplements in these studies.
Non-aggression related outcomes
Six studies reported the effectiveness of nutritional supplementation in reducing depression, improving health-related quality of life, augmenting family and social functioning, reducing hyperactivity, controlling symptoms of autism spectrum disorder, and managing attention deficits.
Mixed effects of supplementation on non-aggression-related outcomes were reported by 13 studies. However, one study reported no significant benefits.
Side-effects
Among 12 studies that monitored the side effects of nutritional supplementation, seven reported mild or moderate intensity side effects in a small fraction of participants. The most commonly reported side effects were nausea, altered bowel movement frequency, vomiting, and headache.
Significance
This systematic review highlights that wide-range vitamin and mineral supplements may have beneficial effects in reducing excessive hetero-aggression in children and adolescents. However, the review indicates that available evidence on the effectiveness of single-nutrient supplements is inconclusive and that the quality and quantity of the evidence on nutritional supplementation is low.
As mentioned by the scientists, this review has focused only on nutritional supplements and not on regular diets, which might also impact aggressive behaviors. Thus, future studies should focus on both dietary habits and nutritional supplements for more conclusive outcomes.
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