Gluten is a protein found in many grains, including wheat, barley, rye and triticale - a cross between wheat and rye. It is a complex of proteins, gliadin and glutelin, which are joined by starch in the endosperm of the grain. Gluten helps food keep its shape by acting as a «glue» that holds food together. Gluten can be found in many types of foods, even ones you wouldn't expect!
Wheat
Wheat is usually found in:
Bread
Nuts, Breadsticks, Croutons
Soups
Pasta
Sauces and salad dressings
Biscuits, cakes
Pastries
Barley
Barley is commonly found in:
Malt (malt flour, malt syrup)
Food colouring
Soups
Beer
Beer yeast
In whichfoods we should check the label before consumption as they may contain gluten?
Energy bars / granola bars - some bars may contain wheat as an ingredient and most use oats which are not gluten free
French fries - watch out for batter containing wheat flour.
Potato chips - some seasoned potato chips may contain malt vinegar or wheat starch
Candies
Soup - pay particular attention to cream-based soups, which have flour as a thickener. Many soups also contain barley.
Tortilla that is not exclusively corn-based may contain a wheat-based ingredient
Dressings for salads and marinades - may contain malt vinegar, soy sauce
Brown rice syrup - may be made with barley enzymes
Meat substitutes made with seitan (wheat gluten) such as vegetarian burgers, vegetarian sausage, plant-based bacon, plant-based seafood (Note: tofu does not contain gluten, but be careful with soy sauce marinades, especially when tofu is fried)
Soy sauce (although wheat-free tamari is gluten-free)
Cold – cut and ready-to-eat meals with meat.
Alcoholic beverages
Alcoholic beverages containing gluten include:
Beers
Malt beverages
Dessert wines
Gluten-free varieties of many of these beverages are available, however. Most distilled alcoholic beverages are also gluten-free.
Foods that are naturally gluten-free
The following grains, legumes, seeds and other starchy foods are naturally gluten-free.
Amaranth
Araruti
Beans
Buckwheat groats (also known as kasha)
Kashawa
Chia
Corn
Flaxseed
Gluten-free oats
Millet
Nut flour
Potato
Quinoa
Rice
Soybeans
Tapioca
Teff
Why do some people need to avoid gluten?
Most people can consume gluten without experiencing side effects, but people with celiac disease cannot tolerate it. People with other disorders such as gluten sensitivity (NCGS) and wheat allergy should also avoid gluten.
Celiac disease
Celiac disease is an autoimmune disease in which the body treats gluten as a threat. To remove this perceived threat, the body overreacts and attacks gluten proteins. This attack also destroys surrounding areas, such as the intestinal wall. Not only can this lead to nutrient deficiencies and serious digestive problems, but it can also increase the risk of many harmful diseases.
People with celiac disease often experience symptoms such as:
Diarrhea or constipation
Acute stomach pain
Stomach discomfort
Bloating
Weight loss
Skin rashes
Some people with celiac disease do not experience digestive symptoms. Instead, they may experience other symptoms such as:
Severe feelings of fatigue
Anemia
Depression
Non-celiac gluten sensitivity (NCGS)
Gluten sensitivity is thought to affect approximately 0.6%-13% of people. People diagnosed with NCGS do not test positive for celiac disease or wheat allergy, but still feel uncomfortable after eating gluten.
The symptoms of NCGS are similar to those of celiac disease and may include:
Stomach pain+
Bloating
Changes in bowel motility
Fatigue
Skin rashes
NCGS can be complex to diagnose because there are currently no specific laboratory or tissue tests for definitive diagnosis.
In conclusion
Gluten-free diets are more popular than ever, but there is often confusion about what gluten is and when it should be eliminated. Gluten refers to a variety of proteins found naturally in grains such as wheat, barley and rye.
There is nothing unhealthy about gluten, but people with certain medical conditions such as celiac disease, gluten sensitivity or wheat allergy should avoid it as it can cause serious adverse reactions. If you suspect you have a gluten-related disorder, consult a qualified doctor. Holland & Barrett provides a wide variety of gluten-free foods and beverages, options that are able to accommodate any preference.
Scientific references
Biesiekierski JR. (2017) What is gluten? Journal Gastroenterology Hepatol. March. 32 Suppl 1:78-81.
Catassi C. (2015) Gluten Sensitivity. Ann Nutr Metab. ;67 Suppl 2:16-26.
Chaudhry NA, Jacobs C, Green PHR, Rampertab SD.(2021) All Things Gluten: A Review. Gastroenterol Clin North Am.Mar; 50(1):29-40.
