The more we learn about the brain, the more we understand how nutrition and supplements can affect its functioning, including moods, attention, and cognition. What a child eats, can profoundly affect the way his or her brain works. And this is true not just in the case of stuttering and tics, but for attention deficit hyperactivity disorder (ADHD), obsessive-compulsive disorder, autism and its related disorders, and many other behavioral and learning problems. All of these conditions are caused by a deficiency in neurotransmitters.

In the case of autism spectrum disorders and ADHD, many parents report great success with a gluten-free, casein-free (GFCF) diet that cuts out milk and wheat. Another common starting point for hyperactive kids is the Feingold diet, which bans artificial flavors, colors, and some preservatives.

Although therapies like these are rarely mentioned by pediatricians, there is a body of well-documented research showing them to be quite effective. At least two wide-ranging reviews of existing research, one conducted by the Center for Science in the Public Interest and the other published in the Journal of Pediatric Child Health, have found that diet and nutritional therapy can noticeably affect some children's behavior. More specifically, a study of 20 children with ADHD published in the Alternative Medicine Review found a regimen of supplements to be as effective as Ritalin. And research among a group of 26 kids (also with ADHD at Cornell Medical Center in New York found that three quarters responded well to a diet that eliminated several problem foods.

The connection between allergies and behavioral disorders can be confusing to parents; how could a sensitivity to dairy products cause a child to be hyper, spacey, or subject to tics? But the chemical released when we have an allergic reaction acts like a neurotransmitter. One neurotransmitter out of balance sets off a chain reaction that can cause all sorts of changes in behavior.

In addition to allergic reactions and sensitivities, many kids with ADHD, autism, Tourette's syndrome, and other disorders have been found to suffer from dramatic deficiencies in certain nutrients, including magnesium, omega-3 fatty acids, and B vitamins. Studies often document the deficiencies without looking at the treatment, but researchers have recently begun following up to see if replacing these missing nutrients can correct behavior problems. In one recent study of 400 ADHD children, for instance, zinc supplements beat placebos in treating certain aspects of the disorder, including hyperactivity and impulsivity.

Changing a child's diet can be a tricky thing. Kids get used to what they like and what works for one child will not necessarily work for another. Since behavioral disabilities and the brain chemistry imbalances that cause them are so complex, parents who opt for dietary treatments must be prepared for a long, frustrating process of trial and error.

Places To Start
Because behavioral disorders are so idiosyncratic, parents can find themselves in a bewildering maze of potential treatments. Here's a guide to the basics of building a dietary strategy.

• Check for food allergies and sensitivities. You can consult an allergist for testing or, if you suspect a certain dietary culprit (sugar is a common one), try eliminating it from your child's diet for several days.
• Check into the Feingold diet. This approach zeroes in on additives and other ingredients that don't necessarily show up on allergy tests. Check out www.Feingold.org, which offers a free email newsletter. Membership in the organization brings other benefits, including guidance on how to follow the diet.
• Consult your fellow parents. There are newsletters, associations, email lists, and support groups for parents of children with every neurological disorder. Ask lots of questions, and find out what's worked for others.
• Find an alternative practitioner well-versed in nutritional therapies. He or she will likely start by testing your child for nutritional deficiencies, then draw up and supervise a plan for addressing them, usually with a mix of dietary changes and supplements. One good way to find such a person is via an online support group for parents of kids with your child's disability.

Persuading Children to Change Their Diet
Although it's difficult to find lunch box options that contain no wheat, dairy, or artificial flavors or colors in your local supermarket, natural food stores like Whole Foods carry a variety of items. Finding healthy food alternatives is not as hard as it seems. Here are some tips:

Find friendly substitutes.
These days, the abundance of new natural food products gives parents more options: Rice milk, for instance, is a fairly painless substitute for cow's milk; soy cheese can replace cheddar; many wheatless breads are available. It's easy to find lunch meats and hot dogs free of preservatives and colorings. And new sugar substitutes like xylitol and stevia make it less painful to turn away from conventional sweets.

Introduce new foods slowly.
Don't try to overhaul your child's whole diet at once or he'll rebel. Plus, you'll never know which foods are the culprits. Instead, eliminate one food at a time. Try going without dairy or wheat for a few weeks and watch for results.

Be clear what's off limits.
Parents need to alert the major players in their kids' lives about dietary no-nos. For many children, even one exposure to a forbidden food-a glass of artificially colored Kool-Aid at soccer practice, say-can trigger a major setback. Make sure that friends, relatives, and teachers understand what you're doing so they can support your efforts.

Time indulgences carefully.
If there's a food your child loves but has trouble with, let have it once in a while on weekends or late in the day when he can act out.

Supplements That Help
Persuading a child to swallow a full-size tablet can be sometimes be impossible. There are some supplement brands that experts and parents recommend for kids with ADHD, Tourette's, obsessive-compulsive disorder, and other behavioral problems. They're available at health food stores and online. Another alternative I recommend is creating a smoothie from the blender with fresh organic fruit and liquid supplements.

• Coromega: an omega-3 supplement that comes in pouches of orange-flavored pudding.
• Attend: contains essential fatty acids, zinc, magnesium, and amino acids, among other ingredients.
• Yummy Greens: an herbal supplement combining organic wheat and barley grass, alfalfa, chlorella, spirulina, and kelp. (Avoid this if your child is allergic to wheat or gluten.)
• ts-PLUS CONTROL: formulated to control tics and compulsions with magnesium, B vitamins, grape seed extract, and other ingredients.
• ts-PLUS Mag-Taurate: contains powdered magnesium taurate.