Celiac Disease in Children: Growth, Testing, and Diet Adherence

When a child isn’t growing like they should, parents often worry about nutrition, sleep, or genetics. But what if the real issue is something hidden in their food? Celiac disease is one of the most common yet underdiagnosed causes of growth problems in kids. It’s not just a stomach upset or food intolerance-it’s an autoimmune condition that attacks the gut every time gluten is eaten. And in children, the signs aren’t always obvious. Many don’t have diarrhea or bloating. Instead, they’re simply shorter than their peers, tired all the time, or struggling to gain weight. The good news? Once diagnosed and managed properly, most kids catch up completely. But that only happens if testing is done right and the diet is followed without compromise.

How Celiac Disease Stops Growth

Celiac disease triggers an immune response when gluten-found in wheat, barley, and rye-is consumed. This response damages the tiny finger-like projections in the small intestine called villi. These villi are responsible for absorbing nutrients. When they’re flattened, the body can’t absorb iron, calcium, vitamin D, or protein properly. For a growing child, that’s catastrophic.

Studies show that up to 90% of children newly diagnosed with celiac disease have some form of growth delay. Their height may fall below the 5th percentile. Weight might be normal or low. Bone age, which measures skeletal maturity, is often delayed by 1.5 to 2.5 years. That delay isn’t a problem-it’s actually a clue. It means the body is still trying to grow, just slower than it should. Once gluten is removed, the villi heal, and the body gets back on track.

There are three common growth patterns after starting a gluten-free diet. Some kids bounce back fast, gaining height rapidly within the first year. Others grow a little slower than normal but keep growing longer, eventually reaching their full potential. A third group grows at a normal rate but takes longer to hit their target height because their bones mature slowly. The key point? Growth recovery isn’t instant. It takes time-often 18 to 24 months. But 85% of children reach their expected adult height if they stick to the diet.

Testing for Celiac Disease: What Actually Works

Many pediatricians still think celiac disease means chronic diarrhea. That’s outdated. Today, the most common reason kids are tested is because they’re short for their age, have delayed puberty, or have iron-deficiency anemia that doesn’t improve with supplements. In fact, up to 4% of children evaluated for short stature turn out to have undiagnosed celiac disease.

The first step is a blood test: tissue transglutaminase IgA (tTG-IgA). This test is over 98% accurate when done correctly. But it’s not enough on its own. You also need to check total serum IgA because 2-3% of people with celiac disease are IgA deficient, which can give false negatives. If the tTG-IgA is more than 10 times above the normal limit, and the child has symptoms and carries the HLA-DQ2 or DQ8 gene (which 95% of celiac patients do), a biopsy might not even be needed. That’s according to the 2020 guidelines from ESPGHAN, the leading pediatric gastroenterology group in Europe.

For others, an endoscopy with biopsy is still required. During the procedure, tiny samples are taken from the small intestine. In active celiac disease, the villi are flattened-what’s called Marsh 3 damage. This is the gold standard. Bone age X-rays of the hand and wrist are also helpful. If the bones are delayed, it’s a strong sign the child will recover height after going gluten-free.

Don’t skip testing just because a child seems “fine” otherwise. Many kids with celiac have no stomach symptoms at all. They might just be quiet, tired, or falling behind in school. That’s why screening is recommended for kids with type 1 diabetes, Down syndrome, or a first-degree relative with celiac. About 5-10% of these children will develop the disease by age 10.

Going Gluten-Free: The Only Treatment

There’s no pill, no shot, no cure. The only treatment for celiac disease is a strict, lifelong gluten-free diet. That means no bread, pasta, cereal, or anything made with wheat, barley, or rye. But it’s not just about obvious foods. Gluten hides in soy sauce, malt flavoring, some medications, and even lip balm. Cross-contamination is a huge problem. A slice of toast in a toaster that’s also used for regular bread can expose a child to enough gluten to trigger damage.

The international standard for “gluten-free” is 20 parts per million (ppm) or less. That’s tiny-but enough to harm someone with celiac. Most grocery stores now carry gluten-free products, but only 15-20% of standard items are safe. And they cost 156% to 242% more than regular versions. That’s a major burden for families.

The good news? Kids often feel better fast. Energy levels improve within 2 weeks. Abdominal pain and bloating clear up in days. Weight gain happens quickly-often 15 to 30 grams per day in infants. But height recovery? That’s slower. It takes 6 to 12 months for antibodies to drop to normal levels. Height velocity increases by 2 to 4 cm per year above expected growth, but full catch-up can take two years or more.

Keeping Kids on the Diet: The Real Challenge

The hardest part isn’t finding food. It’s keeping kids from cheating. Adolescents are especially vulnerable. Social pressure, school lunches, birthday parties, and peer behavior make adherence drop by 25-35% compared to younger children. One 14-year-old told a support group: “I stopped eating gluten-free at school. I got sick every week, but I didn’t want to be the weird kid with the special lunch.”

Parents need support too. Most need 3 to 5 sessions with a registered dietitian who specializes in celiac disease. Learning to read labels takes 4 to 6 months. Common mistakes include assuming “wheat-free” means “gluten-free,” or thinking oats are always safe (they’re often contaminated unless labeled certified gluten-free).

Schools play a big role. In one study, 58% of children with celiac had gluten exposure at school. That’s why a 504 plan is critical. It legally requires the school to provide safe meals, prevent cross-contamination, and train staff. No child should have to risk illness just to fit in.

Regular follow-up is non-negotiable. tTG-IgA levels should be checked every 6 to 12 months. If they stay high, it means gluten is still getting in-either by accident or on purpose. Nutrient levels matter too. Iron, vitamin D, folate, and B12 are checked quarterly. Many kids need supplements for a year or two until their gut heals fully.

What Happens If You Don’t Stick to the Diet?

Some parents think, “My child feels fine now. Maybe they don’t need to be so strict.” That’s dangerous. Even small amounts of gluten keep the immune system activated. Over time, that increases the risk of other autoimmune diseases like thyroid disorders or type 1 diabetes. It also raises the risk of intestinal lymphoma-by two to three times.

Long-term studies show children diagnosed before age 5 and who stick to the diet have a 98% chance of reaching their full adult height. Those diagnosed after age 10? Only 85%. And if they don’t follow the diet? Growth doesn’t recover. Puberty may be delayed. Bone density stays low. The damage isn’t always visible, but it’s there.

There’s hope on the horizon. Clinical trials are testing drugs like larazotide acetate that might help block gluten’s effects. But none are approved yet. Until then, the gluten-free diet remains the only proven solution.

Real Stories, Real Results

One mother in Brisbane shared: “My daughter was 7, in the 5th percentile for height. We tested for celiac because she was always tired. The diagnosis was a shock. But after 6 months on the diet, she gained 3 kg and started growing like a normal kid. By 18 months, she was at the 50th percentile. She’s now 12 and taller than most of her classmates.”

Another parent said: “We spent $200 a week on gluten-free food. It broke our budget. But when we joined a local celiac support group, we found recipes, discounts, and people who got it. Adherence went from 60% to 90%.”

The message is clear: early diagnosis, strict diet, and ongoing support make all the difference. Celiac disease doesn’t have to limit a child’s growth. With the right steps, it can be completely reversed.