Celiac (Gluten sensitivity) Disease: What It Is, How It Feels, and How It’s Treated

Celiac disease is more than “not being able to eat bread.” It is an autoimmune condition, which means the body’s immune system reacts in the wrong way. In celiac disease, this reaction happens when a person eats gluten, a protein found in grains such as wheat, rye, barley, and spelt.

Over time, this immune reaction can damage the small intestine. That matters because the small intestine helps the body absorb nutrients from food. When it is irritated or damaged, people may develop stomach symptoms, tiredness, weight loss, anemia, weak bones, or vitamin deficiencies.

What Happens in Celiac Disease?

In people with celiac disease, gluten triggers the immune system to attack the lining of the small intestine. The damage often affects tiny finger-like structures called villi. These villi help absorb nutrients.

When villi become flattened or damaged, the body may not absorb nutrients well. This is called malabsorption, which simply means the body is not taking in enough vitamins, minerals, fats, or other nutrients from food.

Who Can Get Celiac Disease?

Celiac disease can happen at any age. It may appear in babies after gluten is introduced into the diet, but it can also begin in adulthood, especially in the third or fourth decade of life.

It is more common in women than men and is seen more often in people of northern European background. It also tends to run in families and is linked with certain genes known as HLA-DQ2 and HLA-DQ8.

Celiac disease is also more likely in people who have other autoimmune or related conditions, such as:

• Type 1 diabetes

• Autoimmune thyroid disease

• Autoimmune hepatitis

• Rheumatoid arthritis

• Down syndrome

• Turner syndrome

• Selective IgA deficiency

Having one of these conditions does not mean someone definitely has celiac disease, but it may raise the need for testing if symptoms are present.

Common Symptoms of Celiac Disease

Celiac disease can look different from person to person. Some people have obvious digestive symptoms. Others have mild symptoms or no clear symptoms at all.

Common stomach and bowel symptoms include:

• Long-lasting or repeated diarrhea

• Greasy, foul-smelling stools

• Bloating and gas

• Belly pain

• Nausea or vomiting

• Poor appetite

• Constipation, though this is less common

Celiac disease can also cause symptoms outside the gut, such as:

• Fatigue

• Weight loss

• Iron deficiency anemia

• Vitamin deficiencies

• Weak bones or osteoporosis

• Low calcium levels

• Headaches

• Tingling, burning, or numbness in the hands and feet

• Balance problems

• Depression or irritability

• Reduced fertility or infertility

• A skin condition called dermatitis herpetiformis

In children, celiac disease may cause poor growth, failure to thrive, delayed puberty, or bone and calcium problems.

Why Celiac Disease Is Sometimes Missed

Celiac disease can be hard to recognize because it does not always cause classic diarrhea and weight loss. Some people only have anemia, tiredness, headaches, mood changes, or fertility issues. Others may have symptoms that look like irritable bowel syndrome.

That is why doctors often need a high level of suspicion, especially when symptoms are ongoing or when someone has a family history of celiac disease.

How Celiac Disease Is Diagnosed

Celiac disease is usually diagnosed in two steps:

1. Blood tests first

2. Then confirmation with a biopsy if needed.

• Doctors often start with a blood test called tTG IgA, which looks for antibodies linked with celiac disease. Total IgA is also commonly checked because some people with celiac disease have IgA deficiency, which can make certain tests falsely negative.

  
  

• If blood tests are positive, or if symptoms strongly suggest celiac disease, doctors may recommend an upper endoscopy. During this test, a small camera is passed through the mouth into the first part of the small intestine, and tiny tissue samples are taken. This is called a biopsy.

Under the microscope, doctors may see changes such as:

• Flattened villi

• Overgrown intestinal gland areas, called crypt hyperplasia

• Increased immune cells in the intestinal lining

These findings help confirm the diagnosis.

Do Not Start a Gluten-Free Diet Before Testing

This is very important: starting a gluten-free diet before testing can make blood tests and biopsy results look normal, even if someone truly has celiac disease. For accurate testing, the person usually needs to still be eating gluten.

If someone has already stopped gluten, doctors may consider genetic testing or a supervised gluten challenge. A gluten challenge means gluten is added back into the diet for a period of time before testing. This should only be done with medical guidance.

Treatment: A Lifelong Gluten-Free Diet

The main treatment for celiac disease is a strict, lifelong gluten-free diet. This means avoiding foods made with wheat, rye, barley, and spelt. For most people, symptoms improve after gluten is removed, and the intestine can begin to heal.

Foods that are commonly suitable include:

• Rice

• Corn

• Potatoes

• Soybeans

• Millet

Some people also need iron or vitamin supplements if they have deficiencies. If celiac disease has caused temporary trouble digesting milk sugar, called secondary lactase deficiency, a doctor may recommend avoiding milk products for a time.

Living Well With Celiac Disease

A gluten-free diet can feel overwhelming at first, but many people do very well once they learn what to avoid and what to choose instead. The key is consistency. Even small amounts of gluten may cause problems in some people.

Follow-up is also important. Doctors may repeat blood tests after several months, again at one year, and then yearly. These visits help check healing, nutrition levels, and whether the diet is working.

Possible Complications

When celiac disease is untreated or does not respond well to treatment, complications can occur. These may include nutrient deficiencies, weak bones, secondary lactose intolerance, and a moderately increased risk of certain cancers, including intestinal lymphoma.

A small number of people may develop refractory celiac disease. This means symptoms continue or worsen despite following a strict gluten-free diet for 12 months. This needs specialist care.

Key Takeaways

• Celiac disease is an autoimmune condition triggered by gluten. It can cause digestive symptoms, but it can also affect energy levels, growth, bones, skin, nerves, mood, and fertility.

  
  

• The diagnosis should be confirmed before starting a gluten-free diet, because removing gluten too early can make tests falsely negative.

The good news is that with a strict lifelong gluten-free diet and regular medical follow-up, most people with celiac disease have a very good outlook and can live healthy, active lives.