Jodi Cohen’s second son was an energetic, happy preschooler most of the time. But the mom of two worried about his erratic behavior, shaky focus and “Jekyll and Hyde” mood swings. “I have an older son who is free from any issues with impulse control and focus, so I felt something wasn’t right,” she says.

Cohen tried parenting classes without results. Then a friend mentioned changing his diet. Out of options, she took the suggestion, nixing corn, soy and dairy – so-called inflammatory foods believed to contribute to learning and behavior problems in children – from the family menu. Her “eat clean” efforts paid off. “Right away, he was a calm, sweet kid.”

Cohen never looked back. She was so impressed with the changes to her son’s learning and behavior that she permanently changed her family’s diet and went on to earn a degree in nutritional therapy.

This type of elimination diet (removing foods that may be problematic for a child) and intensive nutritional therapy are wildly popular with parents of children dealing with issues that range from mild problems with focusing to serious neurological disorders. According to the Journal of Developmental and Behavioral Pediatrics, at least one-third of children with autism spectrum disorder (ASD) have used complementary treatments, including dietary supplements and elimination diets.

Proponents of this type of therapy point to life-changing results. “I won’t say I can cure every child [with a neurological disorder],” says Deborah Z. Bain, M.D., a board-certified pediatrician who uses a holistic approach in treating children. But parents report that diet changes are game changers, she says. “They tell me, ‘He’s making eye contact, he’s speaking, he’s a new person.’”

Christina Sakai, M.D., developmental-behavioral pediatrician and pediatric hospitalist at Floating Hospital for Children at Tufts Medical Center, has heard of some of her patients having success, but warns that there is much more research needed to determine whether elimination diets are beneficial. “Certainly, some families report that their child’s symptoms improved dramatically when they tried certain supplements. The one I consistently hear is omega-3 fatty acids; however, it is important to note that there is also very limited high-quality research that demonstrates that this is effective for improving core and associated symptoms of autism.”

Treatment or Cure?

Despite the wide use of special diets for kids with neurocognitive disorders, doctors, dieticians, researchers and parents are split on the issue. Sandra Kimmet, a mom of four, is a doubter. She wanted to find a “miracle cure” for 7-year-old Jasper’s sensory processing disorder and 5-year-old Tabitha’s childhood apraxia of speech, a motor speech disorder. But a gluten-free, sugar-free diet didn’t yield results. She credits her children’s progress to intensive therapy rather than dietary changes. “I so wish there was a miracle diet,” she says. “I’d be all over it!”

“What I tell parents is that we just don’t have enough information to support recommendations for nutritional therapy and/or food avoidance in children with autism,” Sakai says. “Families may be tempted to search the internet, and may find that certain diets are ‘based on research,’ however, it is important to recognize the limitations of these research studies. Specifically, many of them have very small sample sizes, therefore, we cannot generalize well to all children with autism. Currently the best that we can say is that for a certain subgroup of children with autism, diet elimination therapies can improve certain symptoms of autism. Not as a cure, but may reduce autistic mannerisms and increase communication. This subgroup of children generally have known or highly-suspected food intolerance and GI complaints.”

Daniela Ferdico, Psy.D., a pediatric neuropsychologist who treats children with autism, AD/HD and other pervasive developmental diagnoses, agrees. “Parents shouldn’t think of food as a cure, but rather as one tool they can use to help their child.”

Cogwheel offers psychology and therapies along with nutritional counseling, something Ferdico sees as an essential piece of the puzzle for children with neurodevelopmental disorders.

She makes a distinction between treatment and cure: A cure is a one-time solution, whereas treatments are ongoing. Like speech, occupational and behavioral therapies, nutritional therapy is usually ongoing and works best when it’s just one component of a more comprehensive plan, she says.

Nutritional therapy won’t cure autism, Ferdico notes. But it can form the foundation for an effective treatment plan by reducing a child’s level of gastrointestinal pain and distress, enabling him to be more receptive to other therapies. Nutritional therapy does this by stabilizing blood sugar to ward off mood swings and meltdowns that make day-to-day life difficult, and supplying the body with the protein and nutrients required for cognition, she says.

Pinpoint the Plate

Nutritional therapy sometimes involves an elimination diet wherein certain foods are eliminated and then gradually reintroduced to help pinpoint food sensitivities. Researchers have long theorized that foods containing gluten, soy and casein, a protein in milk, may irritate the intestines of sensitive children with autism, contributing to a “leaky gut” that leaches inflammatory proteins throughout the body, impacting behavior, mood and learning. A small Danish study found that inattention and hyperactivity abated for children ages 4 to 10 after 12 months on a gluten-free, casein-free diet, but the gains seemed to plateau when the same kids were tested after 24 months on the diet.

Gluten and casein are potentially problematic because when sensitive individuals can’t properly digest the foods that contain these substances, a buildup of internal inflammation results. This contributes to mental fog, inattentiveness, unresponsive behavior and continued carbohydrate cravings, says Bain. “It’s a feed-forward cycle, where the child eats more and more unhealthful foods and less and less of the nutrients he needs to grow and thrive.”

But aside from the Danish study, evidence on the impact of gluten-free diets is limited. Evidence on the negative impact of food dyes, a common food additive thought to be especially harmful to children with learning disorders, is more robust (artificial food dyes have been linked to behavior problems in children for decades), and new studies are currently under way.

Because elimination diets can get complicated quickly, parents who want to try one should seek out the help of a nutrition expert. Parents shouldn’t simply yank nutrient-dense foods such as grains and cheese from a child’s plate without consulting their pediatrician and a dietician, says registered dietician Kathleen Putnam, M.S., owner of NutritionWorks counseling service. One problem: Removing potentially problematic foods is only part of the picture; those calories need to be replaced with something else, and that something may not be any better than the foods that were eliminated.

Popular elimination diets such as Gut and Psychology Syndrome are gaining ground as a means to treat learning and neurodevelopmental disorders, but the protocol – sticking to a simple diet of mostly meat, fish, eggs, meat stock and fermented foods – can seem daunting to the average busy parent and difficult to maintain over the long term.

Plus, eliminating entire food groups can introduce nutrient deficiencies, complicating an already complex situation, Putnam says. “Nutrition that’s limited can contribute to problematic development, both cognitive and behavioral. Children with AD/HD are often treated with medications that significantly lower the appetite, which is a major concern for growing children.”

Though gluten-free and casein-free diets are still under scientific study, they can be worth trying, with professional guidance, Putnam says. And removing most junky refined carbs, like bread made from highly refined flour, most crackers and cookies, is probably a safe, healthy step for most children.

Replacing refined sugar with fruit-sweetened foods is another change that some parents find worthwhile, says Katie Hurley, author of The Happy Kid Handbook: How to Raise Joyful Children in a Stressful World (TarcherPerigee, 2015). Although a Korean study found no relationship between sugar intake and the development of AD/HD in children, some parents report that removing sweets calms kids down. Whether you’re a believer in elimination diets or a skeptic, eating less junk food never hurt anyone, right?

Nutrition Addition

Once you’ve removed potential problems from your child’s diet, you’re not done: Now, under the guidance of your child’s health care provider, you may need to add or supplement nutrients to replace those you’ve removed, or ones your child was missing before you started. Supplementation can benefit some kids on the autism spectrum; a 2005 study found sleep and digestion improved in autistic children taking a multivitamin supplement.

Magnesium, B vitamins, zinc, omega-3 fatty acids and probiotics are often used and recommended, but parents shouldn’t supplement without consulting a nutritionist or dietician, Bain says, because taking too much of one nutrient can impact others. (For example, excess magnesium can lead to diarrhea, which could reduce absorption of other vital nutrients.) “Nutrients don’t work in isolation,” she notes, and each child’s nutritional blueprint is unique.

Another wrinkle: Children with neurological disorders often have sensitive stomachs – those with autism can be prone to gastrointestinal distress and constipation – and they can be intensely picky eaters, Hurley says. In other words, you can’t simply tell a child to eat a banana or a plate of spinach and expect it to happen. That makes solving nutritional challenges a two-steps-forward, one-step-back dance for many families, and is why vitamin supplements are sometimes needed, at least at first.

Nutritional therapy for spectrum disorders doesn’t have to complicate families’ lives or promote expensive fad diets, says Ferdico. It’s simply one facet of a comprehensive, whole-child care plan. “If a child has stomach pain and isn’t digesting food properly or is so picky that they’re not getting what they need, it’s going to affect cognition and behavior,” Ferdico says. “If you try other therapies without also looking at nutrition, you’re not using all the tools you can use. And we owe it to these kids to use every tool we have.”

Where to Start

A pediatrician or naturopathic physician can order a simple blood test to check for nutritional deficiencies such as low iron, zinc or magnesium. Parents who suspect food sensitivity in their child can ask a pediatric nutritionist or naturopathic physician about immunoglobulin G (IgG) food allergy testing. This blood test can identify food sensitivities to pinpoint the best dietary candidates for elimination from your child’s plate.

Malia Jacobson is a freelance writer.