Common Nutrient Deficiencies in People with Newly Diagnosed/Untreated Celiac Disease
When vitamins and minerals are not absorbed in the intestine, an individual may experience nutrient deficiencies. Diets low in vitamins and minerals may also cause inadequate nutritional intake.
- Malabsorption of many nutrients, including iron, vitamin D, and zinc, are common in a person with newly diagnosed or untreated celiac disease.1
- Even though celiac disease typically damages the upper part of the small intestine (duodenum), the entire small bowel can be affected.2 Vitamin B12, absorbed in the lower part of the small intestine, is a common deficiency seen in celiac disease.2
- Carefully following a balanced, gluten-free diet can help fix low vitamin and mineral levels. It may also be necessary to take gluten-free vitamin and mineral supplements. Speak to your doctor or dietitians about your specific nutrient and supplement needs.
Vitamin and Mineral Deficiencies in Celiac Disease Patients
Calcium
Uses: Builds and maintains strong bones and teeth. Maintains muscle contraction and nerve function. Releases hormones and enzymes that affect multiple body functions.3
Short-Term Signs of Deficiency:
- No obvious symptoms; the body maintains normal calcium levels in the blood by removing calcium from the bones.
Long-Term Signs of Deficiency:
- Thinning of bones (osteopenia)
- Increased risk of more severe bone loss (osteoporosis) and fractures
- Abnormal heart rhythms (serious deficiency)
- Convulsions
- Tingling/numbness of hands
- In children, softening of the bones leading to deformities, short stature, and tooth decay
How Celiac Disease Affects Calcium: Calcium is absorbed in the duodenum. Damage to this absorption site can cause a deficiency in calcium for patients with newly diagnosed or untreated celiac disease. Enzymes that digest lactose (necessary to digest milk sugar) are also damaged, leading to secondary lactose intolerance (lactose intolerance that occurs due to damage of the gut lining).4 Secondary lactose intolerance causes gas, bloating, and loose stools whenever dairy products (such as cow’s milk, yogurt and cheese) are eaten. Visit our section on Lactose Intolerance to learn more.
Iron
Uses: Helps make hemoglobin which transports oxygens from the lungs to the rest of the body. Helps make myoglobin that delivers oxygen to muscles. Helps to make various hormones and connective tissue.5
Short-Term Signs of Deficiency:
- No obvious symptoms; the body stores iron in muscles, spleen, liver, and bone marrow.
Long-Term Signs of Deficiency:
- Iron deficiency anemia
- Fatigue, low energy, poor concentration and memory, shortness of breath
How Celiac Disease Affects Iron: Iron deficiency anemia is a very common symptom of celiac disease. Women who are menstruating (and lose iron through bleeding) or pregnant women and growing children are the most prone to iron deficiency. The gluten-free diet can restore dietary iron absorption and resolve anemia.1 Specific iron supplementation may be needed for some individuals.
Magnesium
Uses: Regulates functions of muscles and nerves. Maintains healthy blood sugar and blood pressure levels. Makes proteins, DNA, and bone.6
Short-Term Signs of Deficiency6:
- No obvious symptoms; kidneys limit the amount of magnesium lost in the urine.
Long Term Signs of Deficiency6:
- Loss of appetite
- Fatigue, weakness
- Nausea/vomiting
- Numbness, tingling, muscle cramps
- Abnormalities in heart rhythm
- Seizures
How Celiac Disease Affects Magnesium: The body needs magnesium for hundreds of enzymatic reactions. Along with vitamin D, it helps the body absorb calcium. Most Americans’ diets are deficient in magnesium, and a standard multivitamin/mineral supplement only contains a small percentage of the recommended Daily Value (DV) of magnesium (450mg).7
Folate
Uses: Needed to help make DNA and other genetic materials. Works with vitamin B12 to help make red and white blood cells. Helps prevent neural tube defects in babies.8
Signs of Deficiency: Anemia that causes fatigue, trouble concentrating, headache, shortness of breath and heart palpitations. Open sores on the tongue and mouth. In pregnant women, increased risk of neural tube defects in developing babies and an increased risk of premature or low birth weight infants.
How Celiac Disease Affects Folate: In the past, folic acid deficiency (folate, otherwise known as B9) was the second most common cause of anemia in celiac disease. Fortunately, more gluten-free foods are now fortified with folate,9making deficiency far less common. Pregnant women or women who wish to become pregnant need a prenatal supplement containing 600 mcg/day and 400mcg/day of folic acid, respectively, in addition to adequate folate in the diet.8
Vitamin B6
Uses: Needed for many enzyme reactions involved in protein metabolism, cognitive development, immune function, and hemoglobin development.10
Signs of Deficiency: Anemia, itchy rash, cracks at the corners of the mouth, and swollen tongue.10
How Celiac Disease Affects Vitamin B6: The gluten-free diet may be inadequate in B6, particularly if all gluten-free grains are avoided. Supplementation with B6 (as well as other B-vitamins) may help improve depression related to celiac disease. Screening for B6 may be indicated.11
Vitamin B12
Uses: Helps form red blood cell. Helps make DNA. Supports brain function. Required cofactor for enzymes in the metabolism of hom*ocysteine (a building block of protein found in the blood).12
Signs of Deficiency:Pernicious anemia, which leads to fatigue, weakness, pale skin, sore and red tongue and mouth, low blood pressure, loss of appetite, heart palpitations, irritability, depression.12
How Celiac Disease Affects Vitamin B12: Vitamin B12 is frequently malabsorbed in patients with newly diagnosed or untreated celiac disease. B12 deficiency can resolve on a gluten-free diet alone; however, specific B12 supplementation may be needed for some individuals.1
Vitamin A
Uses: Helps maintain normal and night vision, immune and reproductive systems.13
Signs of Deficiency: Rare in the US. Xerophthalmia (inability to see in low light), especially in pregnant women and young children.13
How Celiac Disease Affects Vitamin A: Chronic malabsorption can lead to Vitamin A deficiencies, although this is not as common as with Vitamin D. Routine supplementation is not recommended.1
Vitamin D
Uses: Aids in the absorption of calcium, bone growth and development. Helps reduce inflammation and support immune function.14
Short-Term Signs of Deficiency14:
- No obvious symptoms
Long Term Signs of Deficiency14:
- Osteoporosis, leading to fractures
- Rickets (softening/weakening of bones leading to skeletal deformities) in children
- Bone pain
- Osteomalacia (softening of bones) in adults
- Dental deformities
How Celiac Disease Affects Vitamin D: Vitamin D is a fat-soluble vitamin; its absorption from the gut depends on fat absorption. Fat malabsorption in untreated celiac disease can lead to vitamin D deficiency.15 Secondary lactose intolerance may also reduce milk intake, one of the few food sources that contain Vitamin D. Levels of Vitamin D may normalize after 1-2 years on the gluten-free diet, although supplementation may always be required.
Vitamin E
Uses: Acts as an antioxidant that helps protect cells from damage from free radicals (unstable atoms that can cause cell damage, leading to illness or aging). Supports immune function. Helps prevent blood clotting.16
Signs of Deficiency: Nerve and muscle damage, muscle weakness, weakened immune function, vision problems.16
How Celiac Disease Affects Vitamin E: Chronic malabsorption can lead to deficiencies in Vitamin E, although this is not as common as with Vitamin D.1
Vitamin K
Uses: Necessary for normal blood clotting. Some studies suggest that it helps promote strong bones.17
Signs of Deficiency: Easy bruising, delayed clotting, easy bone fracture, low bone mineral density.17
How Celiac Disease Affects Vitamin K: Chronic malabsorption can lead to Vitamin K deficiencies, although this is not as common as with Vitamin D. Routine supplementation is not recommended.1
Zinc
Uses: Assists in immune function. Needed to make proteins and DNA. Supports proper growth and development in infants and children, wound healing, and taste and smell.18
Signs of Deficiency: Slowed growth in infants and children, delayed puberty, impotence in men, hair loss, skin sores, loss of appetite, weight loss, diarrhea, slowed wound healing, decreased sense of taste and smell.18
How Celiac Disease Affects Zinc: Zinc deficiency is common in new or untreated celiac disease (67% of patients in one study).19 Low zinc levels may lead to growth retardation and short stature in children with celiac disease. Studies suggest that zinc levels can rise to normal on a gluten-free diet without requiring additional zinc supplementation, although in some cases, additional supplementation may be important.20
Copper
Uses: Acts as cofactor for many enzymes, including those used in iron metabolism. Maintains healthy immune system, nervous system and brain development.21
Signs of Deficiency: Fatigue, discoloration (lightening) of skin, high cholesterol, connective tissue disorders, weak and brittle bones, balance and coordination issues, increased infection risk.21
How Celiac Disease Affects Copper: Malabsorption can affect copper absorption, but the extent of deficiency in newly diagnosed or untreated celiac disease is not clear.22 Patients should be screened at diagnosis, especially if symptomatic for copper deficiency.15
Recommended Daily Allowance (RDA) of Vitamins and Minerals
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Recommended Daily Allowance (RDA) is the average daily dietary intake level of a vitamin or mineral that meets the nutrient requirements of nearly all (97-98%) healthy individuals in a group.
It is calculated from an Estimated Average Requirement (EAR). If sufficient scientific evidence is not available to establish an EAR and calculate an RDA, an Adequate Intake (AI) is usually developed
View Recommended Daily Allowances (RDA) and Adequate Intakes (AI) for each vitamin and mineral.23
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Please note that individuals with celiac disease may need more than the RDA or AI for specific nutrients.
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Other vitamin and mineral deficiencies in untreated celiac disease are less common and usually only seen in people with longstanding and untreated celiac disease, severe diarrhea, significant weight loss, and malnutrition.13
Too Much of a Good Thing: Vitamin and Mineral Toxicity
- It is possible to take too much of a particular vitamin or mineral, leading to a toxic overdose in the body. The most common vitamins and minerals that can be dangerous in high doses include:
- Iron
- Fat-soluble vitamins: vitamin A, vitamin E, vitamin K and vitamin D*
- Calcium
- B3 (niacin) can be toxic to the liver in high doses
- B6 (pyridoxine hydrochloride) – elevated levels in the blood can cause or worsen neuropathy (numbness and tingling in the extremities)10
- Speak with your doctor or dietitian before starting any supplements to ensure that you are taking the correct amount and for an appropriate length of time.
*Please note that Vitamin D deficiency is very common in celiac disease. High, therapeutic doses are often given to people to restore their vitamin D levels to normal. Do not worry about overdosing on vitamin D if you have been prescribed high doses of vitamin D and are monitored by your doctor.
Take-Home Messages
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Celiac disease can affect the absorption of vitamins and minerals along the entire small intestine.
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Talk to your doctor if you have any of the symptoms above or are concerned that you have nutritional deficiencies – testing is simple. Be sure to follow up with your doctor to review lab results.
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Individuals with celiac disease may need more than the RDA or AI for specific nutrients.
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It is very common for doctors to treat certain nutritional deficiencies with high doses of vitamins and minerals. When this is done, labs are monitored carefully to prevent toxic overload. Do not attempt this on your own.
References
- Theethira TG, Dennis M. Celiac disease and the gluten-free diet: consequences and recommendations for improvement. Dig Dis. 2015;33(2):175-182.
- Hallert C, Svensson M, Tholstrup J, Hultberg B. Clinical trial: B vitamins improve health in patients with coeliac disease living on a gluten-free diet. Aliment Pharmacol Ther. 2009;29(8):811-816.
- National Institutes of Health. Office of Dietary Supplements - Calcium. Nih.gov. Published December 6, 2019.
- Larussa T, Suraci E, Imeneo M, Marasco R, Luzza F. Normal bone mineral density associates with duodenal mucosa healing in adult patients with celiac disease on a gluten-free diet. Nutrients. 2017;9(2):98.
- National Institutes Of Health. Office of Dietary Supplements - Iron. Nih.gov. Published 2016.
- National Institutes of Health. Office of Dietary Supplements - Magnesium. Nih.gov. Published 2016.
- Vici G, Belli L, Biondi M, Polzonetti V. Gluten free diet and nutrient deficiencies: A review. Clin Nutr. 2016;35(6):1236-1241.
- National Institutes of Health. Office of Dietary Supplements - Folate. Nih.gov. Published 2017.
- Saturni L, Ferretti G, Bacchetti T. The gluten-free diet: safety and nutritional quality. Nutrients. 2010;2(1):16-34.
- National Institutes of Health. Office of Dietary Supplements - Vitamin B6. Nih.gov. Published November 11, 2020.
- Valente FX, Campos T do N, Moraes LF de S, et al. B vitamins related to hom*ocysteine metabolism in adults celiac disease patients: a cross-sectional study. Nutrition Journal. 2015;14(1).
- National Institutes of Health. Office of Dietary Supplements - Vitamin B12. Nih.gov. Published 2016.
- National Institutes of Health. Office of Dietary Supplements - Vitamin A. Nih.gov. Published 2017.
- National Institutes of Health. Office of dietary supplements - Vitamin D. Nih.gov. Published 2017.
- Al-Toma A, Volta U, Auricchio R, et al. European Society for the Study of Coeliac Disease (ESsCD) guideline for coeliac disease and other gluten-related disorders. United European Gastroenterol J. 2019;7(5):583-613. doi:10.1177/20506406198441254
- National Institutes of Health. Office of Dietary Supplements - Vitamin E. Nih.gov. Published 2017.
- National Institutes of Health. Office of Dietary Supplements - Vitamin K. Nih.gov. Published 2017.
- National Institutes of Health. Office of dietary supplements - Zinc. Nih.gov. Published 2016.
- Wierdsma N, van Bokhorst-de van der Schueren M, Berkenpas M, Mulder C, van Bodegraven A. Vitamin and mineral deficiencies are highly prevalent in newly diagnosed celiac disease patients. Nutrients. 2013;5(10):3975-3992.
- Singhal N, Alam S, Sherwani R, Musarrat J. Serum zinc levels in celiac disease. Indian Pediatr. 2008;45(4):319-321.
- National Institutes of Health. Office of Dietary Supplements - Copper. Nih.gov. Published 2017.
- Goodman BP, Mistry DH, Pasha SF, Bosch PE. Copper deficiency myeloneuropathy due to occult celiac disease. The Neurologist. 2009;15(6):355-356.
- National Institutes of Health. Nutrient Recommendations: Dietary Reference Intakes (DRI). ods.od.nih.gov.
Revision Date: February 24, 2022
Editors: Amy Keller, MS, RDN, LD and Melinda Dennis, MS, RDN, LD
