Nutritional deficiencies and supplements

Iron deficiency

Unexplained iron deficiency anaemia is a common symptom of undiagnosed coeliac diseaseA condition where a person is unable to eat gluten as it makes their body attack itself. (1). The prevalence of patients with iron-deficiency who are then found to have coeliac disease is 4.7% (2).

Serum tests in 26 children with established coeliac disease showed folic acid and iron status were low in 30% of children compared to 14% of controls (3).

The British Society of Gastroenterology (BSGBritish Society of Gastroenterology - an organisation focused on the promotion of gastroenterology within the United Kingdom, with a membership drawn from physicians, surgeons, pathologists, radiologists, scientists, nurses, dietitians, and others interested in the field. The BSG is a registered charity.) provides guidance on the treatment of iron deficiency anaemia (4). All people with low iron levels should have iron supplementation both to correct anaemia and replenish blood stores.

Magnesium deficiency

A study of 41 patients found that 20% of people with coeliac disease had a magnesium deficiency (5). This is a concern as magnesium deficiency impairs parathyroid hormone (PTH) secretion and thus affects bone turnover. Deficiency can lead to osteopenia (6). Supplementing patients with magnesium has been shown to increase PTH secretion and bone mineral densityThe strength of your bones. The lower your bone mineral density, the greater your risk of breaking bones. Bone mineral density is measured by having a bone density scan known as a Dual Energy X-ray Absorptiometry (DEXA) scan. in patients with coeliac disease.

Calcium deficiency

It is important that people with coeliac disease meet their calcium requirements to reduce the risk of osteoporosis. The calcium requirements for adults with coeliac disease are greater than the general population. Those who can not meet their needs from diet alone may require additional supplements.

Zinc deficiency

Zinc levels can be low on diagnosis of coeliac disease. A study looked at zinc absorption in people newly diagnosed with coeliac disease in comparison to those who have been on a gluten-freeWhen a food has less than 20 parts per million (ppm) of gluten so it is safe for people with coeliac disease to eat. diet for some time. Zinc absorption was low in the newly diagnosed group but absorption corrected itself in those who had complied with the glutenA protein that is found in the cereals wheat, barley and rye. -free diet (7).

Ensuring nutritional needs are met

Following a gluten-free diet presents a problem with achieving adequate intake of some nutrients. Foods that contain gluten are a good source of B vitamins, calcium, vitamin D, iron, zinc, magnesium and fibre. Therefore, removing them from the diet can have an effect on the amount of these nutrients in the diet.

Specialist gluten-free products, especially those obtained on prescription, are an important source of energy, carbohydrate, NSP, calcium and iron (8). These products can help in meeting all the nutrients in the diet.

There is no evidence to suggest that nutritional deficiency is a significant problem in individuals diagnosed with coeliac disease and established on a gluten-free diet (9). 

Assessing people with coeliac disease for nutritional deficiencies

Poor compliance to the gluten-free diet after diagnosis of coeliac disease can result in ongoing deficiencies. If the gluten-free diet is not followed there is a higher chance of low nutrient levels not being corrected. 

People who are newly diagnosed with coeliac disease should be assessed for any nutritional deficiencies. This is normally done by a blood testBlood is taken from someone who is being tested for coeliac disease. . Nutrient levels can also be monitored in follow up appointments to check that the gut has repaired and nutrients are being absorbed.

If people with coeliac disease are deficient in any vitamins or minerals, these need to be corrected by taking a supplement. Any supplements that are taken should be checked to ensure they are gluten-free.

Deficiencies of these nutrients will usually correct themselves after a gluten-free diet has been started. This is because the body will start to absorb nutrients more effectively.

References

1. NICENational Institute for Health and Clinical Excellence - an independent organisation responsible for providing national guidance on promoting good health and preventing and treating ill health. NICE had produced a clinical guideline on the recognition and assessment of coeliac disease. (2009) Coeliac Disease: Recognition and assessment of coeliac disease. www.nice.org.uk

2. Patterson R & Johnson SD (2003) Iron deficiency anaemia: are the British Society of Gastroenterology guidelines being adhered to? Postgraduate Medical Journal. 79(930): 226-228.

3. Haapalahti M, Kulmala P, Karttunen TJ et al (2005) Nutritional status in adolescents and young adults with screen-detected celiac disease. J Pediatr Gastroenterol Nutr. 40 (5): 566-70. 

4. Goddard F, James MW, McIntyre AS et al (2005) Guidelines for the management of iron deficiency anaemia. British Gastroenterology Guidelines.

5.  Rujner J, Socha J, Syczewska M et al (2004) Magnesium status in children and adolescents with coeliac disease without malabsorption symptoms. Clin Nutr. 23(5): 1074-9.

6. Rude RK & Olerich M (1996) Magnesium deficiency: possible role in osteoporosis associated with gluten-sensitive enteropathy. Osteoporos Int. 6(6):453-61.

7. Crofton RW, Glover SC, Ewen SWB et al (1983) Zinc absorption in celiac disease and dermatitis herpetiformisUsually shortened to DH, this is a form of coeliac disease where the skin is affected with small blisters.: a test of small intestinal function. Am J Clin Nutr. 38: 706-12.

8. Kinsey L, Burden ST & Bannerman  E (2008) A dietary survey to determine if patients with coeliac disease are meeting current healthy eating guidelines and how their diet compares to that of the British general population. European Journal of Clinical Nutrition. 62: 1333- 1342.

9. Robins, G, Akobeng A, Kirk E et al (2009) A systematic literature review on the nutritional adequacy of a typical gluten-free diet with particular reference to iron, calcium, folate and B vitamins. Food Standards Agency website.