If you have coeliac disease that is untreated or undiagnosed (you are still eating gluten), several complications can occur. If you have coeliac disease, it is crucial that you do not eat any gluten.
It is a common misconception that eating a little bit of gluten will not do you any harm. Eating even tiny amounts can cause the symptoms of coeliac disease and increase your risk of developing the complications outlined below.
Osteoporosis
Osteoporosis is a condition that causes your bones to become brittle and weak. Your bones need a wide variety of vitamins and minerals to stay dense and strong.
If you have coeliac disease, you have an increased risk of developing osteoporosis due to the effect on your digestion. The damage gluten causes to your intestines (gut) prevents enough nutrients being absorbed into your bones from the food that you eat.
Osteoporosis can be treated with supplements that strengthen the bones, such as vitamin D and calcium. More severe cases of osteoporosis may require medication.
See the Health A-Z topic about Osteoporosis - treatment for more information about treating the condition.
Malnutrition
As coeliac disease causes your digestive system to work less effectively, severe cases can sometimes lead to a critical lack of nutrients in your body. This is known as malnutrition, and can mean your body is unable to function normally or recover from wounds and infections.
If you have severe malnutrition, you may become fatigued, dizzy and confused. Your muscles may begin to waste away, and you may find it difficult to keep warm. In children, malnutrition can cause stunted growth and delayed development.
Treatment for malnutrition usually involves increasing the number of calories in your diet.
See the Health A-Z topic about Malnutrition - treatment for more information about treating malnutrition.
Lactose intolerance
If you have coeliac disease, you are more likely to also develop lactose intolerance, a reaction to milk sugar (lactose) that is found in dairy products. Lactose intolerance causes symptoms such as bloating and abdominal discomfort. The damage to your digestive system, caused by gluten, may also make it difficult for you to digest lactose.
Lactose intolerance can be effectively treated by not eating and drinking dairy products that contain lactose. You may also need to take calcium supplements because, as dairy products are an important source of calcium, you will need to compensate for not eating them.
See the Health A-Z topic about Lactose intolerance - treatment for more information about treating lactose intolerance.
Cancer
Some research has suggested that having coeliac disease can increase your risk of developing certain types of cancer, including:
- bowel cancer
- lymphoma (cancer of the lymphatic system, which is part of the immune system)
The same piece of research found that people with coeliac disease have a lower risk of developing lung and breast cancer, although the reasons for this are unclear.
It is estimated that people with coeliac disease are twice as likely to develop bowel cancer compared with the general population. However, this is still a very small increase in risk: only 1 in every 200 people with coeliac disease will develop bowel cancer in the first 10 years after diagnosis. As age is an independent risk factor for bowel cancer, your risk of developing bowel cancer increases as you get older, in line with the general population.
The risk of developing cancer is thought to be highest during the first year after diagnosis, before dropping off to normal as your gluten-free diet starts to take effect.
Whether or not you have coeliac disease, it is important to be aware of the symptoms of bowel cancer, which include:
- bloody or black stools (faeces)
- weight loss
- abdominal (stomach) pain
- lymphoma, which includes symptoms such as painless swellings in your neck or armpit, unexplained fatigue and night sweats.
See your GP if you develop these symptoms.
See the Health A-Z topics about Bowel cancer and Lymphoma for more information.
