Diet, Nutrients and ADHD - What does the latest research say?
Are you one of us with ADHD who finds it difficult to determine what's reasonable when it comes to food and vitamins? Have you ever read about dietary supplements and the brain, and then rushed to order everything you can find that more or less dubious actors want to sell you? If so, you're in good ADHD company, and this text is for you!
ADHD is a diagnosis that affects many children and adults worldwide. While medication is an essential part of evidence-based treatment, there is growing research interest in the role of diet.
However, one thing remains clear: maintaining a moderately healthy diet and lifestyle benefits both children and adults, whether they have ADHD or not.
New study 2023
In 2023, a new review study was published (1), summarizing the results of multiple research papers on the subject. Here, we provide a summary of the findings from those studies, as well as the questions that still remain unanswered.
But first:
It’s important to note that much of the research is still uncertain or inconclusive. However, it’s useful to understand the progress made so far.
The reasons for these uncertain results include small sample sizes, failure to account for other influencing factors, or simply too few studies.
Scientific research needs to be replicated to confirm results before guidelines and recommendations can be established.
What are researchers investigating?
Different studies examine different aspects. Some explore whether ADHD symptoms can be treated through diet, i.e., if dietary changes can reduce symptoms.
Others focus on whether ADHD can be prevented or its development delayed in children.
Nutrients and minerals
Magnesium: Some studies show that individuals with ADHD may have lower magnesium levels. A small study where magnesium and vitamin D were given as supplements showed promising results.
But much more research is needed before proving that it’s both safe and effective.
Zinc: The results here vary significantly. Some studies show lower zinc levels in people with ADHD, while others do not.
Zinc supplements might be something to consider for children, but just like magnesium, we know too little about the safety and effectiveness to make any recommendations.
Iron: Iron deficiency in infancy might be linked to ADHD later in life.
However, it seems that brain iron levels, rather than blood iron levels (which are what we can measure), might affect potential ADHD symptoms.
Vitamin D: Some evidence suggests that vitamin D levels may be lower in children with ADHD.
Supplements have shown certain improvements in ADHD symptoms in some studies.
Omega-3
Despite initial enthusiasm for omega-3 supplements, newer studies and meta-analyses have not shown any significant benefit. Not for children or adults with ADHD.
Probiotics
Early research on probiotics for ADHD is intriguing, but so far the evidence is very limited.
A small study showed improved quality of life. However, more research is needed before it can be confidently said that probiotics have an effect.
Dietary patterns
Several studies indicate that a "healthy diet," meaning a diet rich in vegetables, fruits and whole grains, may be linked to reduced ADHD symptoms.
Conversely, a "Western" diet, rich in processed foods, sugar, and unhealthy fats, may be linked to increased ADHD symptoms.
However, it is important to remember that it’s still unclear whether it’s the diet that affects ADHD symptoms, or if ADHD symptoms lead to poorer dietary choices.
Elimination diets – Limiting certain foods
So-called elimination diets have shown early and cautiously promising results, with up to 60% of children in some studies showing significant reductions in ADHD symptoms.
The elimination diet involves removing certain selected foods, or even entire groups of food, and then gradually reintroducing them to identify whether a specific food worsens symptoms.
Long-term studies show that, for the right person, the benefits may last for several years.
More research is needed before this can be recommended as an additional treatment for ADHD. It’s also important to note that it can be harmful to eliminate too many foods in small and growing children.
This isn’t something to experiment with on your own; rather, it should be discussed with a dietitian and your child’s healthcare provider.
Conclusions of the study
It is unclear whether supplements benefit individuals with low concentrations of minerals, vitamins, or omega-3 fatty acids.
The effect of supplements can vary due to comorbidities, complicating studies. Whether supplements of certain nutrients are effective remains to be investigated.
High doses of seemingly healthy minerals, vitamins and other nutrients can carry the risk of serious side effects and harm.
ADHD symptoms can vary for many reasons. And because we cannot measure ADHD changes with specific biomarkers (such as blood tests) it’s more challenging to prove the effect of specific nutrients and diets.
There’s not enough evidence to recommend supplements, omega-3 or probiotics in the management of ADHD at this time – more research is needed.
There’s an ongoing complex interaction between biological, environmental and social factors that affect ADHD symptoms.
This means that the solution for managing ADHD will never involve just the intake or exclusion of certain nutrients or a specific diet.
The links between ADHD and dietary habits can also be explained by what is called "reverse causality." This means that ADHD symptoms may lead to certain food choices rather than the other way around.
Thus, even though diet and nutrients likely play a role in ADHD, there is no universal solution. Generally, healthy dietary and lifestyle habits are beneficial for all, with or without ADHD.
Always consult with healthcare providers before making major dietary changes or starting supplements to manage ADHD.
🥗
Lotta Borg Skoglund
MD PhD & Letterlife Co-founder
Reference:
1. Lange KW, Lange KM, Nakamura Y, Reissmann A. Nutrition in the Management of ADHD: A Review of Recent Research. Curr Nutr Rep. 2023 Sep;12(3):383-394. doi: 10.1007/s13668-023-00487-8. Epub 2023 Jul 28. PMID: 37505402; PMCID: PMC10444659.