Symptoms of celiac disease occur after eating foods containing gluten. These foods trigger an abnormal immune system response that damages the intestine. Symptoms vary widely: they may be very mild and go completely unnoticed, or they may be severe and impact daily life.

Common symptoms related to celiac disease may come and go. They include:

• Gas, abdominal swelling, and bloating. These symptoms result from a failure of the small intestine to absorb nutrients from food. You may also have mild stomach pain, but it is usually not severe.
• Abnormal stools. Diarrhea or bulky, loose (or watery), pale, frothy, and foul-smelling stools often occur. The stools may contain a large amount of fat and may stick to the sides of the toilet bowl, making them hard to flush. Although children and adults often experience the same types of symptoms, intestinal problems, such as constipation, are more likely to occur in children.
• Weight loss. Adults and children may have unexplained weight loss despite having a normal appetite. Younger children may fail to gain weight and grow as expected, a condition known as failure to thrive.
• Fatigue and weakness. Celiac disease can result in a general lack of energy and strength. Sometimes poor nutrient absorption causes fatigue and weakness.
• Vomiting. Some people may get sick after eating gluten. Children are more likely than adults to have this reaction.

Celiac disease may also lead to:

• Osteoporosis and other bone problems related to a lack of calcium absorption.
• Anemia caused by iron deficiency and/or folic acid deficiency.
• Infertility or having more than one miscarriage.
• Delayed onset of puberty.
• Frequent respiratory infections.
• Problems with memory and concentration.
• Irritability in children. And adults may show signs of depression.

Symptoms of celiac disease also occur with a variety of other conditions, which can delay the initial diagnosis.