Attention-deficit/hyperactivity disorder (ADHD) is one of the most common neurobiological conditions in the world. It typically emerges in childhood and may persist through adulthood, causing symptoms like hyperactivity, short attention span, and impulsive behavior. 

Despite assumptions about ADHD and nutrition, clinicians don’t have clear dietary guidelines to help improve patients’ lives. Although certain ways of eating are linked to ADHD symptoms, such as diets high in processed foods and sweets, a lack of strong evidence makes it difficult to recommend supplementation or generalized restrictive diets across the board. 

Micronutrients and supplements

A systematic review of the role of iron and zinc in ADHD has identified the potential benefits of these micronutrients in reducing ADHD symptoms.

Granero R, Pardo-Garrido A, Carpio-Toro IL, et al. The role of iron and zinc in the treatment of ADHD among children and adolescents: a systematic review of randomized clinical trials. Nutrients. 2021;13(11):4059.

Both minerals act as dopamine reuptake inhibitors, with similar targets as stimulant medications used to treat ADHD. 

Children with low iron stores at baseline benefit from iron supplementation, but the evidence isn’t as convincing to supplement kids without a deficiency.

Currently, the evidence best supports supplementation with vitamin D, but only in the presence of a deficiency, according to a review in Nutrients of dietary patterns in ADHD.

Pinto S, Correia-de-Sá T, Sampaio-Maia B, et al. Eating patterns and dietary interventions in ADHD: a narrative review. Nutrients. 2022;14(20):4332.

Harmful foods and additives

The Nutrients review found that dietary patterns described as being high in empty calories and processed foods are associated with the risk of ADHD, whereas diets rich in fruits, vegetables, and micronutrients (such as the Mediterranean diet, DASH diet, and vegetarian diet) are inversely associated with the disorder.

In fact, as the researchers noted, “The Western pattern, rich in red and processed meats, refined cereal grains, soft drinks, and hydrogenated fats, was shown to increase the risk of ADHD by 92%.”

Dietary interventions

Despite important contributions from studies on dietary patterns and ADHD, there are some key problems that limit the value of this data. Dietary patterns are complex and require arbitrary decisions and interpretation. Dietary pattern research tends to focus on specific populations, which isn’t always scalable to other groups. In addition, observations about dietary patterns fail to identify specific triggers, leading to potentially unnecessary restrictions and rules.

Elimination diets, such as the few-foods diet, or the oligoantigenic diet, can help identify specific food hypersensitivities or allergies that may exacerbate ADHD symptoms. These diets start by eliminating most foods, gradually reintroducing them one by one. Although tedious, undergoing an elimination diet can be highly effective in pinpointing problematic foods, according to researchers writing in Current Nutrition Reports.

Lange KW, Lange KM, Nakamura Y, et al. Nutrition in the management of ADHD: a review of recent research. Curr Nutr Rep. 2023;12(3):383–394.

Up to 60% of participants have achieved significant improvements in ADHD after 4 weeks of adhering to the few-foods diet.

As current research cannot confirm a cause-and-effect relationship between diet and ADHD, elimination diets open the door for tailored recommendations. However, practitioners must use caution when prescribing an elimination diet due to the potential for nutrient deficiencies and growth impacts in children.