Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by inattention, hyperactivity and impulsiveness. It affects around 5% of children globally. While the exact causes of ADHD are unknown, research suggests diet can play a role. Certain foods and ingredients may worsen ADHD symptoms in some children. This article reviews foods that may need to be limited or avoided in an ADHD diet.
Summary
– Refined grains, added sugars and processed foods are linked to worse ADHD symptoms. Kids may benefit from eliminating or reducing intake of sodas, sweets, white bread, pasta, pizza and fast food.
– Artificial food colorings and preservatives may worsen hyperactivity and inattention in children with ADHD. Consider avoiding brightly colored candy, fruit snacks, powdered drink mixes and colored condiments like ketchup.
– Trans fats from partially hydrogenated oils have been associated with unfavorable changes in children’s memory, ability to pay attention and behavior. Limit fried foods, margarine, frozen pizza, microwave popcorn and packaged baked goods.
– Pesticide residues on conventionally grown produce may exacerbate ADHD symptoms. Buying organic fruits and vegetables may help reduce exposure to pesticides.
– Gluten and casein are proteins found in wheat, rye, barley and dairy. These proteins are broken down into peptides that may affect brain function and worsen ADHD symptoms in some children. Removing sources of gluten and casein from the diet may help.
– Artificial food additives like artificial sweeteners, flavors and colors have also been linked to behavioral problems in children with ADHD. Limiting exposure to these additives may help control symptoms.
– Omega-3 fatty acids like those found in fatty fish are important for brain health. Kids with ADHD may benefit from increasing omega-3 intake from seafood, walnuts and flaxseeds.
Foods to Limit or Avoid in an ADHD Diet
1. Refined Grains and Added Sugars
Refined grains like white bread, pasta and white rice have had the fiber- and nutrient-rich outer bran layer removed during processing. This leaves mostly easily digestible starch.
Fiber helps slow the digestion and absorption of carbohydrates, leading to steady blood sugar levels. Refined grains lack fiber, so they cause rapid spikes in blood sugar and insulin levels compared to whole grains (, ).
These blood sugar fluctuations may worsen inattention and hyperactivity in children with ADHD (, ).
One study including 117 children with ADHD found they exhibited significantly more hyperactive and oppositional behaviors when fed high-glycemic foods like refined wheat products and sugary foods ().
Products made with refined grains are also high in added sugars. Higher sugar intake is linked to worse attention and behavior in children, especially those with ADHD (, ).
Limiting refined grains and added sugars may help control ADHD symptoms. Here are some sources to reduce or avoid:
– Breads, crackers, cereals, baked goods and pastas made from refined grains like white flour
– Sodas, sweetened beverages, fruit juices, candies and ice cream
– Pizza, macaroni and cheese, pasta with white sauce
– Fast foods and fried foods
2. Food Colorings and Preservatives
Food additives like artificial food colorings and preservatives may exacerbate hyperactivity and other ADHD symptoms in children (, ).
One study found that removing artificial food colorings and benzoate preservatives from the diets of children with ADHD significantly reduced hyperactivity (, ).
Food colorings are used to make processed foods appear more appealing. Children consume high levels from brightly colored candy, fruit-flavored snacks and drinks.
Common food preservatives like sodium benzoate and nitrites are added to foods to increase shelf life. But for sensitive children, they may trigger ADHD symptoms.
Some foods to avoid with artificial colorings and preservatives include:
– Candy, especially brightly colored gummy and sticky candy
– Fruit-flavored snacks like fruit rolls, leathers and chews
– Cereals with food colorings on the grain pieces
– Powdered drink flavoring mixes with bright colors
– Colored condiments like ketchup, mustard and relish
3. Trans Fats
Trans fats are produced by heating liquid oils in the presence of hydrogen gas. This creates unhealthy fats that are solid at room temperature.
Shortenings, margarines, deep fried fast foods, microwave popcorn, frozen pizza, packaged cookies and pie crusts tend to be high in trans fats.
These artificial trans fats are linked to inflammation, insulin resistance and heart disease in adults (, ). There’s also concern they could affect children’s brain health and behavior.
One study looked at the diets of 627 children. High intake of trans fats was associated with poorer ability to pay attention, memory problems and unfavorable behavior, compared to children who ate less trans fat ().
Reducing trans fats in your child’s diet may help avoid these complications. Limit fried foods, margarine, frozen pizzas, microwave popcorn and packaged baked goods made with hydrogenated or partially hydrogenated oils.
4. Pesticides in Produce
Pesticide residues in fruits and vegetables may exacerbate ADHD symptoms.
One study assessed urine concentrations of pesticide metabolites in 1,139 children. Children with high intakes had double the odds of an ADHD diagnosis ().
Another review found children eating the most organic produce had significantly lower ADHD rates. This was attributed to less exposure to pesticides and synthetic fertilizers ().
Pesticides may interfere with brain neurotransmitters and worsen ADHD symptoms in children ().
When possible, buy organic produce or wash produce thoroughly. Peeling fruits and vegetables may also reduce pesticide exposure.
5. Gluten and Casein
Gluten is the main protein found in wheat, barley and rye. Casein is the predominant protein in dairy products.
These proteins are common food intolerances, especially in children with ADHD (, ).
One study found that 39 of 50 children with ADHD had elevated antibodies against gluten, indicating a sensitivity ().
Another study found that 27 of 30 children with ADHD had significantly improved concentration after following a gluten-free, casein-free diet for 5 months ().
When digested, gluten and casein release peptides called gluteomorphins and caseomorphins. These peptides may travel past the blood-brain barrier and disrupt brain function, worsening ADHD symptoms (, ).
If you suspect your child may have a gluten or casein intolerance, discuss removing these foods from their diet with your doctor or dietitian.
6. Artificial Food Additives
Food additives like flavors, sweeteners and colorings may worsen hyperactivity and inattention in children with behavioral problems like ADHD (, , ).
One study in 288 preschool children found additives increased hyperactivity, especially in children with concentration difficulties ().
Another controlled trial studied the effects of diet in 50 children with ADHD. Removing artificial food colorings, preservatives and high-salicylate foods significantly reduced ADHD symptoms ().
Common artificial food additives that may trigger symptoms in sensitive children include:
– Artificial sweeteners: aspartame, saccharin, sucralose
– Monosodium glutamate (MSG)
– Nitrates and nitrites
– Sodium benzoate, BHA, BHT, TBHQ
– Caramel coloring
– Yellow #5, yellow #6 and other food dyes
If your child seems especially sensitive to certain foods, limiting or avoiding artificial additives may help control ADHD symptoms.
7. Omega-3 Fatty Acids
Omega-3 fatty acids play important roles in the brain.
Children with ADHD tend to have lower blood levels of omega-3 fatty acids like eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (, ).
Supplementing with fish oil, EPA and DHA may relieve ADHD symptoms, including inattention, impulsiveness and aggression (, ).
Kids with ADHD should also ensure they get adequate omega-3s from their diet. Focus on increasing these omega-3-rich foods:
– Oily fish like salmon, herring, mackerel and sardines
– Walnuts
– Flaxseeds
– Chia seeds
Other Tips to Manage ADHD
Besides limiting foods that may exacerbate symptoms, several other dietary tips may help kids with ADHD:
– Eliminate snack and junk foods so they don’t spoil their appetite for nutritious meals.
– Serve more fiber-rich foods like vegetables, fruits, beans and whole grains to help sustain energy and concentration.
– Make sure they eat a protein-rich breakfast every morning, such as eggs, yogurt and nut butter on whole grain toast.
– Stay hydrated by drinking plenty of water throughout the day.
– Get plenty of omega-3s, vitamins B6, B9 and zinc through a daily multivitamin.
– Consider testing for food sensitivities like gluten, casein and additives to see if limiting any improves symptoms.
– Work with a nutritionist knowledgeable about ADHD diets for personalized advice.
Conclusion
Multiple dietary factors may worsen ADHD, especially for children sensitive to certain foods.
Limiting refined grains, added sugars, fried foods, artificial food additives and pesticide residues may help reduce hyperactivity and inattention.
Ensuring adequate intake of protein, omega-3s, vitamins and minerals is also important.
Testing for food intolerances and sensitivities may reveal problem foods. Removing gluten, casein or food additives from your child’s diet under medical supervision may improve their symptoms.
Incorporating more nutritious whole foods while limiting potentially harmful ingredients can go a long way in managing ADHD.