Helicobacter pylori (H. pylori) is a common type of bacteria that grows in the digestive tract and has a tendency to attack the stomach lining.

Most cases of H. pylori infection cause no symptoms. Yet for millions of people, warning signs and symptoms can occur.

For example, a person may notice a metallic taste in his or her mouth, usually occurring 2 to 3 hours after eating a meal.

H. pylori infection may also result in chronic hoarseness or sharp, persistent stomach pains, especially after eating spicy or fried foods.

Gastritis — a burning or cramping after eating irritating foods — is the most common symptom of H. pylori infection.

Gastritis is inflammation in the lining of the stomach, called the mucosa, which can be accompanied by significant erosions of the stomach lining, leaving the area raw and sensitive.

This can also result in slow bleeding from the raw surface, which over time can lead to anemia, secondary to a loss of iron.

As the problem progresses, a person may notice that he or she cannot eat a full meal, which can lead to significant weight loss.

Chronic infections are often associated with iron deficiency, because the body begins to sequester iron in order to deny this essential growth element to invading bacteria.

Chronic cough and recurrent sore throat can also happen with this type of infection. Some people even suffer from chronic and recurrent sinusitis.

One of the less-appreciated symptoms of H. pylori infection is hypoglycemia, or low blood sugar, which can become severe and even debilitating — especially after eating sweets or drinking highly sweetened beverages.

In severe, prolonged infections, a person may experience more severe symptoms, including:

• Bleeding ulcers

• Anemia

• Difficulty swallowing (dysphagia)

• Recurrent vomiting

• Unexplained weight loss

• Inability to eat a whole meal because of stomach fullness after just a few bites

These are considered alarm signs because they can be indications of much more serious complications, including cancer.

Fullness after a small meal can indicate impaired gastric emptying.