Written by Lisa Kunstler, FodShop Nutritionist and Group Fitness Instructor

Introduction to Coeliac Disease

Coeliac Disease (CD) is an autoimmune disease, whereby the body rejects consumption of gluten. Gluten is a protein found in wheat, barley, oats and rye, and when consumed, causes inflammation and damage to the small intestine. (1)

Without treatment, individuals with CD can experience severe symptoms and health concerns, such as infertility, gastrointestinal discomfort, liver disease, depression, weight loss, osteoporosis and anaemia. (1) The only treatment for CD is a long-term gluten free diet that heals the bowel and improves health outcomes. (1)

The small intestine is lined with minuscule, finger-like projections called 'villi', which help to digest and absorb nutrients in food. (1) Without complete avoidance of gluten, villous atrophy occurs, which is when the villi become inflamed and flatten, reducing the intestinal surface area available for nutrient absorption. This is the major cause for nutritional deficiencies in patients with CD. (1)

Breaking Down At-risk Nutrients

Listed below are some common micronutrients that are essential to the diet. There are many more but the nutrients below are the top ones at risk of depletion in CD with adherence to a gluten free diet. 

Iron

The role of iron in the body is to create haemoglobin and myoglobin in the blood, an oxygen transporter between the lungs and the rest of the body. It is also in charge of the creation of many hormones and connective tissues. (2)

When an individual is deficient in iron for a long period of time, they may experience fatigue, shortness of breath, poor concentration and memory and low energy, many signs of a condition called iron deficiency anaemia (IDA). (2)

Individuals most prone to iron deficiencies include menstruating women, pregnant women, and growing children. Those with CD are especially at risk of IDA however, following a gluten free diet is essential to restore dietary iron absorption in the gut and prevent anaemia. (2)

Calcium

Calcium is used by the body to maintain strong bones and teeth, muscle contraction and nerve function. It is also in charge of releasing hormones and enzymes that impact various bodily functions. (2) Some long-term signs of calcium deficiencies include thinning of bones, abnormal heart rhythms, osteoporosis/fractures, numbness in the hands, and convulsions. (2)

As calcium is absorbed in the small intestine, a damaged gut from gluten in CD can decrease calcium absorption. Enzymes necessary to digest lactose are also damaged and this can cause secondary lactose intolerance in patients with CD. This may include symptoms such as, loose stools, bloating and gas when consuming dairy. (2)

Vitamin B12

Vitamin B12 (VB12) is essential in red blood cell and DNA production as well as brain function. When an individual is deficient in VB12, they may show signs of low blood pressure, fatigue, weakness, pale skin, loss of appetite, irritability, and more. (2)

VB12 is frequently malabsorbed in untreated CD patients. Following a gluten free diet is the best way to combat this type of deficiency. (2) Eating gluten free foods high in VB12 such as eggs, beef, chicken, fish, fortified gluten free cereals, low-fat milk, yoghurt and cheese are wise options.

Vitamin B6

Vitamin B6 (VB6) is required for enzyme reactions that are responsible for cognitive development, immune function and more. When deficiency in VB6 exists, one may suffer from itchy rashes, a swollen tongue, anaemia, and cracks at the corners of the mouth. (2)

A gluten free diet may discourage VB6 consumption, especially if gluten free grains are avoided. (2) A great option for foods high in VB6 include fish (tuna, salmon), poultry, chickpeas, fortified gluten free cereals, bananas, dark leafy greens and cantaloupe. 

Zinc

Zinc's role is to assist immune function, proteins and DNA creation, wound healing, taste, smell and growth and development in children. Signs of deficiency include delayed growth in children, weight loss, loss of appetite, diarrhoea, slowed wound healing and delayed puberty. (2)

A deficiency can be common in untreated CD (67% of patients). Following a gluten free diet will help restore levels. (2) It is important to eat foods high in zinc such as oysters, red meat, poultry, beans, and dairy.

Vitamin D

Vitamin D (VD) is essential for absorbing dietary calcium, as well as for bone growth and development, inflammation reduction and immune function. A long term deficiency can lead to osteoporosis and fractures, rickets, dental deformities and bone pain. (2)

VD is absorbed dependent on fat absorption in the gut. Fat malabsorption in untreated CD can be a serious concern for VD deficiencies. Secondary lactose intolerance is also a concern, as milk is high in VD but is limited due to increased gastrointestinal symptoms. (2)

After following a gluten free diet for 1-2 years, levels of VD may normalise. It is important to get lots of sun for VD absorption as well as consume foods high in the vitamin such as oily fish, egg yolks, mushrooms, fortified orange juice, and red meat. (2)

Nutrient Deficiency risks: CD vs IBS

Although it is better researched and understood, micronutrient deficiencies are not only caused by CD. Following a low FODMAP diet for the management of IBS and IBS-type symptoms can also present some risks.

Below is a chart to highlight the differences in deficiency risks between the two; 

How to Combat Nutrient Deficiencies 

Following a long term gluten free diet is essential for those with CD but with so many deficiency risks, what is the next step?

Maintaining a well-balanced, gluten free diet is the key to preventing micronutrient deficiencies. Some gluten free foods high in essential minerals and vitamins include:

• Vegetables
• Fruit
• Meat
• Legumes
• Quinoa
• Gluten free whole grains (buckwheat or millet)
• Dairy or calcium rich plant-based milks

If you believe you are at risk of deficiency in any of the above-mentioned nutrients, it is best to contact your general practitioner or Accredited Practising Dietitian (Australia) or Registered Dietitian (NZ, Canada & USA).

Supplementation may be necessary, but it will depend on the advice given by your health care professional. 

Final Thoughts

CD is a disease that causes the body to reject gluten consumed in wheat and wheat-containing foods.

Without treatment of the disease with a long-term gluten free diet, CD patients can experience severe symptoms and health conditions including abdominal pain, infertility and osteoporosis.

Paired with CD is the likelihood of micronutrient deficiencies, best combatted by a well-balanced, healthy, gluten free diet. Foods such as vegetables, fruits, meats, dairy milks and legumes are great options to increase consumption of minerals and vitamins in a long-term gluten free diet and minimise risk of deficiencies. 

References

1. Coeliac.org.au. 2022. Coeliac Australia. [online] Available at: <https://www.coeliac.org.au/s/article/Coeliac-disease> [Accessed 3 August 2022].

2. Bidmc.org. 2022. Nutritional Deficiencies in Celiac Disease. [online] Available at: <https://www.bidmc.org/centers-and-departments/digestive-disease-center/services-and-programs/celiac-center/celiacnow/nutrition-and-the-gluten-free-diet/nutritional-considerations-on-the-gluten-free-diet/common-nutritional-deficiencies-in-people-with-celiac-disease#:~:text=Malabsorption%20of%20many%20nutrients%2C%20including,diagnosed%20or%20untreated%20celiac%20disease.&text=Even%20though%20celiac%20disease%20typically,small%20bowel%20can%20be%20affected.> [Accessed 3 August 2022].