But, I would like to add to a little more to this simple statement. More accurately, YOU ARE WHAT YOU ABSORB. If you don't absorb the nutrients from the food you are eating, then the expression "You are what you eat" won't be true. All the healthy food in the world won't help you if you are unable to break down and absorb the nutrients in the food you eat. The same is true of vitamins--if you can't break them down and absorb them, then they might be a waste of money.
Some children are excellent at absorbing nutrients from food. Their bodies are efficient at breaking down food and extracting every last bit of nutrition from the food. These are children who might be able to eat a relatively unhealthy diet and still grow and thrive.
Other children aren't as efficient at breaking down food and despite a relatively healthy diet, they will have growth problems and vitamin deficiencies. Children who eat healthy diets but whose growth or development are not optimal might need to check vitamin status to make sure that they are properly absorbing nutrients. Mainstream doctors can do some tests to assess vitamin levels as well as test for gluten intolerance and allergies, but often an alternative or integrated doctor will do a better job assessing the overall nutritional status of a patient.
One of the main symptoms of celiac is malabsorption of vitamins and fats. This malabsorption of vitamins and fats can lead to growth, learning, behavioral and health problems. Because of our family's inability to absorb nutrients, even a nutrient dense, gluten free diet was not enough to prevent nutrient deficiencies. Two nutritionists told me that my daughter had the worst absorption they had ever seen--one said her absorption was worse than the worst case of IBD that she has seen. It is a huge relief for me, that after treatment for an underactive thyroid and the biofilm protocol, both my children's absorption of nutrients has improved.
I, myself, developed a nerve problem from vitamin deficiencies. Testing revealed I was low in copper, carnitine, B12, and arganine (an amino acid.) I was told that several of the vitamins I was low in were absorbed in the same area of the intestine indicating that absorption might be a factor. Pinpointing and addressing these deficiencies resulted in my nerve problem getting better.
My point is--everyone is different. While a nutrient dense, gluten free diet might be a necessity for some children, for others, it might not be enough and specific supplementation might be necessary. Some kids would quickly come unraveled eating a diet of mostly processed foods, but other children can thrive on whatever they eat.
Of course, everyone, in theory, would do better eating a healthier, less processed diet and I try to educate parents how many problems can be a symptom of poor nutritional status. But, I also try to remember that everyone is different and what is right for me and my family might not be necessary for others.
Mainstream and Alternative Testing for Food Allergies and Vitamin Deficiencies