Children with chronic celiac disease have a high risk of developing poor bone health, says a study conducted at the University of Alberta.
Diana Mager, an assistant professor of clinical nutrition for the U of A’s Department of Agriculture Food and Nutrition Sciences, studied 43 children between three and 17 years over a one-year period.
In the study published recently in the European Journal of Clinical Nutrition, she concluded that children in Alberta are at risk for low bone mineral density due to a lack of sun exposure and poor absorption of essential vitamins and minerals. The article specifically cited a deficiency of vitamin D, vitamin K and calcium in 30 to 35 per cent of the children.
“It is one of the few diseases where the treatment is diet therapy, and in the clinic we’re seeing how challenging it is to dramatically change the dietary intake and see kids’ bone health improve,” said Mager.
Chronic celiac disease is an autoimmune disorder causing intolerance to gluten found in wheat, rye, barley and oats.
The digestive system is lined with villi – microscopic, finger-like projections that absorb nutrients. When a person with celiac disease eats gluten, it causes an immune system reaction where the body starts damaging and destroying the villi.
Without villi, the body is unable to absorb nutrients and without adequate nutrition, a child’s body has a difficult time staying healthy and growing properly.
Several common symptoms of celiac disease are diarrhea, decreased appetite, stomach pain, bloating, weight loss and stunted growth.
Mager cites three main factors for a patient’s poor bone health.
“Malabsorption is the big one. The small bowel is so damaged to exposure to gluten it can’t always absorb vitamin D and vitamin K and calcium. Secondly, half the kids don’t feel well, so they don’t eat well. Thirdly, in Alberta with a decrease to light exposure, our skin can’t make vitamin D very well. And in the summer, even though we have a higher prevalence of sunlight, parents put sun block on their kids because of skin cancer. So kids just don’t get enough.”
While vitamin D has long been associated with the absorption of calcium for developing strong bones and teeth, it’s only in the last 10 years that researchers have begun to realize the significance of vitamin K for bone development, Mager said.
“We’ve known it influences and supports coagulation and blood-clotting, but now we’re learning that osteocalcin, a bone protein, affects the matrix of bone building. If you don’t have enough vitamin K, it won’t be biologically active and if it’s not biologically active, the formation of new bone will be affected,” Mager said.
The blood work conducted during the study suggested that 25 per cent of children had a low vitamin K intake. Major sources of vitamin K are green leafy vegetables, asparagus, broccoli, cucumber and liver.
Mager recognizes that it is a constant struggle for children with celiac to meet daily nutritional requirements and she recommends supplements, in particular for vitamin D absorption. The minimum recommended daily intake for children is 600 international units per day.
“Eat fatty fish such as salmon and lots of leafy green vegetables and fortified vitamin D dairy products,” she said. “And read the labels.”
For more information, check out Dietitians of Canada at www.dietitians.ca and the Canadian Celiac Association at www.celiac.ca.
