Celiac Disease Screening Test
was added to your cart!

Celiac Disease & Vitamin Deficiencies: Facts You Should Know

Medically reviewed by


Celiac Disease Screening Test

Understand your body’s reaction to gluten with a comprehensive at-home celiac test.

Questions About Your Health?

Curious what your blood has to say about your current health? Try a test today.

Take the guesswork out of lab work

Our new Symptom Checker analyzes your symptoms to find the right health test for you.


Recent medical research has shown that newly diagnosed celiac disease sufferers are most commonly deficient in a range of vitamins, including niacin, vitamin A, vitamin B6, folate, vitamin B12, vitamin D, and riboflavin, to name just a few. Vitamin deficiencies in celiac patients are usually also accompanied by other nutritional deficiencies, most notably folic acid, zinc, iron, magnesium, calcium, and even protein.

However, it’s worth keeping in mind that there are other potential causes of vitamin deficiencies besides celiac disease, such as excessive alcohol consumption, kidney disease, Crohn’s disease, certain medications, and cancer, among others. For this reason, it’s crucial to talk to your physician first and get tested for celiac disease before you go on a gluten-free diet which may also limit your vitamin intake.

Working with a dietician and staying informed is the best way to ensure a trouble-free life when you have celiac disease.

That’s why we’ve put together this list of six important facts that you need to know about the connection between celiac disease and vitamin deficiencies.

What is Celiac Disease?

Celiac disease is a digestive disorder characterized by an inflammatory reaction to gluten, a popular protein found in barley, rye, wheat, and other cereal grains. When a patient with celiac disease consumes foods or drinks containing gluten, the immune system mistakenly attacks the small intestine, causing insurmountable damage to the villi, finger-like structures within the small intestine that help absorb vitamins and other nutrients.

If left untreated for a long period, celiac disease will eventually cause enough damage to the small bowel that it can no longer properly absorb nutrients. This is called malabsorption.

Mineral and vitamin deficiencies are some of the common symptoms of celiac malabsorption. However, most celiac patients also exhibit digestive issues like stomach aches, bloating, gas, constipation, diarrhea, and abdominal cramps. This malabsorption can also result in multi-systemic health conditions such as osteoporosis (in which bones become brittle), anemia, delayed growth, neurological disorders, infertility, miscarriage, and other reproductive problems.

Compounding these health complications, celiac disease may increase the risk for–or occur in conjunction with–other autoimmune disorders, such as cardiomyopathy, autoimmune hepatitis, Addison’s Disease, autoimmune thyroiditis, rheumatoid arthritis, and type-1 diabetes.

Today, celiac disease affects roughly 3 million Americans; that’s about 1 percent of the entire US population, according to the University of Chicago Medicine Celiac Disease Center. To put it another way, Americans diagnosed with celiac disease would fill more than 936 standard cruise ships!

Worse still, many experts think the condition is underdiagnosed, with some saying over 97 percent of celiacs are undiagnosed.

Celiac disease is primarily a familial hereditary disorder — specifically, people with first-degree relatives (siblings, father, and mother) with the disorder have 1-in-22 odds of developing it during their lifetimes.

What Causes Vitamin Deficiencies in Patients with Celiac Disease?

In patients with untreated celiac disease, malabsorption is squarely to blame for nearly all nutritional deficiencies, including vitamin deficiencies. When a celiac patient continues to consume gluten, the immune-induced inflammation on the walls of the small intestine destroys epithelial cells and flattens the essential villi. This not only causes distention and pain but also leads to nutrient malabsorption.

When a healthy person takes vitamins and vitamin-containing foods, they are usually digested in the stomach and then moved to the small bowel. This is where the absorption of all your vitamins occurs. For instance, water-soluble vitamins like beta-carotene, B complex vitamins, folate, and vitamin C are singled out and absorbed into the bloodstream in the first section of the small intestine called the jejunum.

When you have celiac disease, however, malabsorption means most vitamins aren’t absorbed into the body and end up in the rectum instead, along with the undigested matter. This leads to vitamin deficiencies and, in prolonged cases, vitamin deficiency anemia. Take vitamin B12 deficiency, for instance. The B-complex vitamin has been found to be deficient in between 8 percent and 41 percent of patients with untreated celiac disease depending on the extent of intestinal damage.

Fact #1: Vitamin Deficiencies May Comprise the Only Symptom of Celiac Disease

Some people with celiac disease may have experienced certain symptoms resulting in a diagnosis early in life. However, others may show very vague symptoms or none at all, which means diagnosis will be delayed or never happen.

In fact, according to Dr. Joe Murray at Mayo Clinic, as many as half of the adults with celiac disease go undiagnosed because of two reasons: (i) they went on a gluten-free diet before diagnosis, meaning the blood test returns a false negative result, or (ii) they don’t show any typical symptoms like extreme fatigue, chronic diarrhea, unexplained weight loss, emaciation, and constipation.

Just because a person is asymptomatic doesn’t mean that the damage to their small intestine isn’t happening. For such cases where the symptoms are vague or absent, vitamin deficiencies may be the hallmark symptom of the condition.

In this recent study published in Mayo Clinic Proceedings, Dr. Murray and his colleagues compared 309 newly diagnosed celiacs without typical malabsorptive symptoms to controls from the general population.

The scientists found folate deficiency in 3.6 percent of the celiac patients, as compared to 0.3 percent in the general population. The same trend was seen in vitamin B12, which was deficient in 5.3 percent of celiacs and only 1.8 percent of the controls.

This should be a huge wake-up call for primary care physicians and those at risk of celiac disease. In other words, patients with low vitamin levels should get tested for the condition even if asymptomatic.

Fact #2: Vitamin Deficiencies May Cause Brittle Nails and Hair Loss

A broad range of factors may cause your nails and hair to become brittle, the most common being biotin deficiency. The chief role of biotin is to convert sugar into energy. As a water-soluble vitamin, biotin (also called vitamin B7) is among the first nutrients to be affected by celiac-related malabsorption. In fact, biotin deficiency is the reason for hair loss often being linked to celiac disease. In addition to celiac patients, heavy drinkers, expectant mothers, and people with Crohn’s disease are at the greatest risk of biotin deficiency.

The most noticeable signs of vitamin B7 deficiency are splitting, thinning or brittle nails and hair, but other symptoms may include tingling in the feet, muscle pain, chronic fatigue, and muscle cramps.

Fact #3: Vitamin Deficiencies May Lead to Bleeding Gums

While using the wrong toothbrush can cause your gums to bleed, the real culprit is vitamin C deficiency. A water-soluble vitamin, vitamin C plays a critical role in gums’ health and in the prevention of cell damage, as well as in immunity and wound healing. An antioxidant, vitamin C is an essential vitamin, which means the body doesn’t make it on its own. Because it’s absorbed in the jejunum ⁠— the primary site of small intestine inflammation — vitamin C deficiency is common in untreated celiac patients. A long-term deficiency of vitamin C has been found to cause dental problems, including bleeding gums, weak teeth, and even tooth loss. It’s no wonder untreated celiac disease may sometimes be associated with bleeding gums and dental issues.

Fact #4: Vitamin Deficiencies May Cause Poor Vision or Vision Loss

A nutrient-deficient diet, especially one low in vitamins, can sometimes lead to vision problems. For one, vitamin A deficiency linked to untreated celiac disease has been known to cause night blindness, an eye condition characterized by a person’s inability to see at night or in low light.

The reason behind this is that vitamin B is essential for making a retina pigment called rhodopsin which helps with night vision. Even worse, some medical studies have shown that untreated night blindness can turn into xerophthalmia, an eye complication that damages the cornea and eventually causes total blindness.

Find out more about the connection between celiac disease and eye health.

Fact #5: Vitamin Deficiencies May Worsen Restless Leg Syndrome (RLS)

Better known as Willis-Ekbom disease or RLS/WED, restless leg syndrome (RLS) is a neurological (affects the nerves) condition in which the person experiences uncomfortable and unpleasant leg sensations, as well as the irresistible urge, to move the legs. This condition affects twice as many women as men, and as per the National Institute of Neurological Disorders and Stroke, roughly 10 percent of people in the US are affected by RLS. While iron deficiency is the main cause, vitamin C deficiency may also lead to restless leg syndrome. In addition to a gluten-free diet, celiacs should load up on vitamin C-rich and iron-rich fruits and veggies.

Fact #6: Vitamin Deficiencies Can Cause Mouth Ulcers

Canker sores – or mouth ulcers as they are technically known – often occur because of B-vitamin and iron deficiencies, both of which can be caused by celiac-related malabsorption.

In a 2013 review published in the Journal of Clinical and Diagnostic Research, scientists reviewed existing medical literature and several past studies. They found that more than 28 percent of patients experiencing recurrent mouth ulcers had deficiencies in iron, pyridoxine (vitamin B6), riboflavin (vitamin B2), and thiamine (vitamin B1).

Celiac patients with canker sores should reinforce their gluten-free diets with dark leafy greens, legumes, fish, meat, and poultry, as well as lots of B-vitamin-rich fruits.


Celiac disease causes inflammation and destruction of the small intestine, leading to severe malabsorption which, in turn, results in vitamin deficiencies. These vitamin deficiencies have been linked to numerous multi-systemic conditions and health problems such as diabetes, anemia, hair loss, eye problems, mouth ulcers, bleeding gums, brittle nails, dandruff, and even infertility.

The best course of treatment is to embrace a strict, lifelong gluten-free lifestyle, allowing the small intestine to heal, reversing these vitamin deficiencies.

Updated on
April 15, 2021
Read more
Understand your body’s reaction to gluten with a comprehensive at-home celiac test.
Shop now


Subscribe to get the latest articles sent straight to your inbox

Thank you for signing up!
Oops! Something went wrong while submitting the form.