Gluten is protein complex with glutenin and gliadin as its components. It is commonly found in certain whole grains such as wheat, barley, and rye. The name “gluten” for this protein is originated from its property of acting as a glue to hold food substances together. When wheat flour and water are mixed and kneaded, hydration of the gliadin and glutenin proteins leads to the formation of gluten, forming a sticky 3D network structure. Continuous kneading action gives stretch on the gluten complexes and strengthens its elasticity, which makes the resulting elastic dough. During baking, rising agents in the dough will make gluten as well as the baked goods to expand and rise, giving the tender and soft texture. Other than bread, cakes, and pizza, gluten is widely applied in various food production processes, ranging from the preparation of pasta and sauce to ice-cream and confectionery.

Generally, gluten does no harm to healthy individuals. Only celiac disease patients and people who have other medical conditions associated with gluten (e.g. non-celiac gluten sensitivity) are not suitable for consuming gluten-containing foods. The allergic symptoms for non-celiac gluten-sensitive people include abdominal bloating, diarrhea, rash or swollen throat, etc. As for celiac disease patients, their physiological responses to gluten are more vigorous, which can cause severe medical issues. According to the Celiac Disease Foundation, every 1 in 100 people in the world suffers from celiac disease (an autoimmune disease). The immune system of these patients automatically recognizes gluten as foreign invaders (like bacteria) in the small intestine and initiates a series of immune responses that damage the intestinal lining. The defective intestinal lining will allow direct passage of toxic substances from the small intestine into the blood as well as hinder normal nutrient absorption, resulting in malnutrition problems.

If you are a celiac disease patient or have other medical conditions related to gluten, it is better to exclude foods that contain gluten in your diet (i.e. gluten-free diet) to alleviate the allergic immune response. However, wheat, barley, and rye are rich in potassium, magnesium, iron and B vitamins. You will be missing out these nutrients if you avoid eating foods made from these grains. In addition to taking supplements, these nutrients can definitely be found in other food items from daily diet! 

Q: Is a gluten-free diet healthier than a normal diet? Is this diet pattern applicable to all people?

Gluten-free diet is specifically beneficial to people who are allergic to gluten and celiac patients. Gluten does no harm to normal healthy individuals so it is unnecessary for us to go gluten-free. Gluten-free diet is not healthier than a normal diet because the meaning of gluten-free only represents that the food does not contain gluten while this is not exactly linked to more health benefits. For example, white rice is a gluten-free food but its glycemic index is much higher than wheat, which may lead to weight gain easier. Plus, many food manufacturers would add even more sugar and oil into their gluten-free products to improve the mouthfeel and tender texture of the foods, which would then result in even higher calories! Besides, wheat, barley and rye are nutrient-dense whole grains. You will need to pay attention to the missing nutrients (e.g. iron and the B vitamins) from gluten-free diet and ensure supplementation from other foods, especially when you are/at risk of having anemia and vitamin B deficiency diseases.

Q: How to choose gluten-free food products?

When choosing food products, apart from looking for the gluten-free label on the food package, you should also be aware of warning claims like “this product may contain gluten” and “made in a factory that may also process wheat products”. Even though the food is claimed to be gluten-free, it could be cross-contaminated with gluten-containing ingredients during production. For example, oatmeal is considered a gluten-free food while the food factories may process other grains that cause the existence of a trace amount of gluten in the final oatmeal products. However, it is still considered to be gluten-free if there is less than 20ppm of gluten per 100g of the food item. To choose smart, you should check for the contents of added sugar and oil in the gluten-free food product. It will be a high-sugar product if there is more than 15g of added sugar per 100g and a high-fat product if there is more than 20f of total fat per 100g. Besides, gluten-free diet followers are often at risk of lacking certain micronutrients such as potassium, magnesium, iron and the B vitamins so it is a good approach to note whether the gluten-free items have fortified with these nutrients.