What does gluten-free really mean?

When you Google gluten-free you are inundated with memes about gluten-free haircuts, gluten-free water and how the rest of the world is sick of hearing about it. But how many people actually know what it means to be gluten-free in the case of coeliac disease, or understand what coeliac disease is?

Coeliac disease is a permanent autoimmune disease which causes the immune system to attack the body when you eat gluten from wheat and other grains. The damage to the gut causes symptoms like diarrhoea and bloating. Nutrient absorption may be impaired so people often have anaemia or feel fatigued. Growth in children may be affected. And, because the gut is damaged, there may be intolerance to lactose, at least temporarily until the gut starts to heal when gluten is rigorously avoided.

PhD student Katie Pedley is investigating the long-term effects of coeliac disease. She has already completed her Bachelor of Science in Human Nutrition and Physiology and her interests in Coeliac Disease led her to want to do research in this area.

“Sadly, for sufferers of coeliac disease, there is no cure,” she says. “They have to avoid gluten for their whole lives – as indicated by this year’s theme for Coeliac Awareness Week ‘Together we are GF for life’.”

So how is coeliac disease diagnosed? “Blood tests can identify antibodies in the blood which are raised in coeliac disease because the gut is damaged,” Ms Pedley says. “Genetic testing can show whether genes which occur more frequently in people with coeliac disease are present. Confirmation of coeliac disease is usually done by a gastroenterologist taking minute samples of gut tissue which can be examined under a microscope to detect damage to the lining of the gut. The tests have to be done before the person starts a gluten-free diet. If the tests are positive then it is extremely important to avoid all sources of gluten.”

Ms Pedley’s tips for people diagnosed with coeliac disease:

Avoid cross contamination - even a very small amount of gluten can lead to intestinal damage

• Although straight forward in theory, it is actually a lot more complicated. The availability of “gluten-free” food in cafes and restaurants across the country is increasing but just because food is gluten-free by ingredient does not mean it is safe to eat.
• When purchasing food from a cabinet it is important to consider the shelf the food is on - are there any items on the shelf above which could drop crumbs? Does the item come into contact with any foods containing gluten? Are there separate utensils used for the gluten-free foods?
• When purchasing cooked/hot food consider asking your server if the food was prepared with cross contamination in mind. For example, at a café which provides gluten-free toast – was the bread toasted in a gluten-free only toaster, or were items fried in a cooker or oil only cooking gluten-free foods.

Learn to read labels

• Although some products may state that they are gluten-free or display the crossed grain logo, not all gluten-free products are advertised as such. It is very important for someone with, or catering for, coeliac disease to learn to identify gluten in ingredient lists. For all products manufactured in New Zealand or Australia allergens must be identified. When checking ingredient lists you should be looking for wheat, barley, rye, oats and gluten – if these are not listed on the ingredients or allergens list, a product should be gluten-free. Products may also state whether they “may contain” these ingredients, making it very difficult to know whether foods are safe.
• Exceptions to this rule include caramel, glucose syrup, dextrose derived wheat and maltodextrin. Although these products are derived from wheat they are heavily processed, and gluten is no longer detectable.

Ms Pedley’s PhD thesis is being supervised by Professor Marlena Kruger from Massey Institute of Food Science & Technology.