Gluten is the latest enemy in a long line of nutrition targets. It is harmful for people with the autoimmune disorder celiac disease. But despite celiac affecting only 1 percent of the U.S. population, everyone seems to be jumping on board the gluten-free bandwagon.
In fact, the growing “gluten-free movement” is becoming very popular with parents as a way to treat their children’s mental or behavioral problems.
But is gluten the problem? And does going gluten-free help?
Gluten is not the culprit
According to the National Foundation for Celiac Awareness, research associating mental health to a gluten-free diet is limited. “We haven’t found any evidence that gluten is causing any symptoms in anybody except in celiac disease,” says Dr. Stefano Guandalini, founder and medical director of the University of Chicago Celiac Disease Center, “And I stand by this very strongly.”
However, research has found a link between people with diagnosed celiac and cognitive problems, such as forgetfulness, confusion, difficulty concentrating and lapses in memory. Cases of anxiety, behavioral problems and depression in celiac patients have also been reported.
Here’s a quick look at what some research has found:
A 1998 study found that one-third of celiac patients have depression. A 2003 study says teenagers with celiac have a 31 percent risk of developing depression compared to 7 percent in nonceliac adolescents. It’s unclear if celiac actually caused their depression or if other factors played a role.
A more recent study in 2012 surveyed 177 women with celiac disease who adhered to a gluten-free diet. The results revealed 37 percent exhibited clinical signs of depression and 22 percent exhibited clinical signs of disordered eating. But, as The Boston Globe notes, the study fails to establish if the depression or eating disorder came first.
Researchers assessed 441 study participants with celiac disease on a gluten-free diet in June 2010. Their findings, published in World Journal of Gastroenterology, concluded depression was not elevated in the celiac participants compared to the general population. However, anxiety was nearly three times higher in female celiac patients than in the general population.
Anxiety is found in connection with celiac both before and after diagnosis. It often develops due to the nervousness and worry over symptoms associated with celiac. Anxiety can also develop around the societal complications of managing the disease and worry over cross-contamination.
The gluten-free casein-free diet (GFCF) is the most popular autism diet. Casein is the protein found in many dairy products. The Interactive Autism Network (IAN) reports 16 percent of families with autistic children use dietary restrictions. While some parents report improved behavior when their autistic children are on GFCF, this success may be from other excluded ingredients, such as high-fat and high-sugar foods.
The Autism Speaks Autism Treatment Network (ATN) launched an investigation into whether a gluten- and dairy-free diet help treat autism. The medical investigation found no clear evidence that these diets benefit people with autism who do not have celiac.
In the only double-blind crossover study on gluten and autism, results showed a gluten-free diet did not benefit people with autism and is not a sufficient treatment option. The researchers do note that other studies have shown positive results from gluten-free diets; however, the profile of the participants in those studies is unclear.
A 2010 study conducted by a researcher from Golisano Children's Hospital at the University of Rochester Medical Center also confirmed a GFCF diet is not an effective treatment for children with autism. Still, parents seem to think it’s working, as stated in a 2012 Penn State study based on survey results from parents of autistic children.
In a 2011 Italian study, 67 individuals with ADHD followed a gluten-free diet for six months. Of the 67 participants, 10 were confirmed with celiac disease. For the people with celiac, following the diet improved their behavior compared to before the diet. However, 10 participants is a very small sample size to draw any conclusions for the entire celiac population.
A 2006 study involving 132 participants of various ages with celiac disease were analyzed for ADHD-type symptoms both before and after beginning a gluten-free diet. Using a behavior scale, the researchers found participants’ scores improved significantly within a brief period of time after following the gluten-free diet. Note: These improvements are specific to patients with both celiac disease and ADHD only.
A positive celiac association
“There is no doubt that there is a profound connection between active celiac disease and a number of psychological/behavioral issues,” explains Dr. Guandalini. This is especially the case in children. Newly diagnosed patients have reported better performance in school because they are more focused and have better problem-solving. He says many children with celiac are initially introverted, sad and irritable. “All of these, especially in young children, disappear quite quickly when they go on a gluten-free diet,” he explained. This indicates strong evidence of a cause-effect relationship between celiac disease and mental health.
But, as noted above, a gluten-free diet does not appear to be an effective treatment for mental health problems in those who do not have celiac disease.
But why and how would celiac disease affect mental health?
Some speculate it’s the malabsorption of vitamins and minerals that promote serotonin production and regulate mood, such as zinc, tryptophan, and B vitamins. But Dr. Guandalini advises against rushing to conclusions.
Doctors previously thought malabsorption caused osteoporosis in celiac patients but now find calcium levels aren’t affected. So defaulting to the malabsorption theory isn’t always accurate. He says doctors don’t know if malabsorption or something else is the cause for the celiac-mental health connection.
More time and research is needed to fully understand this relationship and the mechanisms behind it.