If you have celiac disease or gluten intolerance, your body is unable to properly digest gluten, a protein in wheat and some other grains. If this is the case, consuming gluten can result in diarrhea, cramping and bloating -- and you may have to follow a gluten-free diet to remain symptom-free. Understanding which foods contain gluten can help you know what you can and cannot eat.

Choose Gluten-Free Grains

Wheat is forbidden on a gluten-free diet because it contains gluten. You cannot eat wheat products such as white or wheat bread, pretzels, pasta or wheat-containing breakfast cereals. Other gluten-containing grains to avoid include:

• rye
  
• triticale
  
• bulgur
  
• barley
  
• couscous
  
• durum

You can use nut and soy flours as alternatives to wheat flour if you are baking.

Know Which Foods Are Naturally Gluten-Free

You can have most products that do not contain grains. A gluten-free diet allows all fresh fruits and vegetables and all frozen and canned fruits and vegetables as long as they contain no sauce. Breaded vegetables are off-limits, according to New York University Langone Medical Center 1. Nuts and peanuts are naturally gluten-free as well. Avoid breaded meats, poultry and fish.

Watch for Unexpected Gluten-Containing Foods

Some foods, such as sauces and marinades, can unexpectedly contain small amounts of gluten. NYU Langone Medical Center warns that you need to avoid teriyaki sauce, soy sauce and malt vinegar on a gluten-free diet 1. Many meat marinades and fruits in thickened sauces contain gluten. Use gluten-free foods instead to flavor your foods. You can have mustard, herbs and other vinegars on a gluten-free diet. Beer and some nondairy beverages, such as soy and rice milk, have gluten, but you can have distilled alcohol.

Other Considerations

Some foods, such as yogurt and oats, are unlikely to contain gluten, but they may. Only consume varieties of such products if their labels claim that they are free of gluten. The U.S. Food and Drug Administration regulates labeling claims for the food industry and sets strict standards on when foods may carry gluten-free labels. Some people choose to follow a gluten-free diet before being diagnosed with gluten sensitivity or celiac disease, but NYU Langone Medical Center explains that clinical researchers have not uncovered any benefits to doing this 1.