Medical nutrition therapy is the only accepted treatment for celiac disease. This paper summarizes a review of scientific studies using the gluten-free diet, nutritional risk factors, controversial elements of the diet, and its implementation in treating celiac disease. Treatment for celiac disease requires elimination of the storage proteins found in wheat, rye, and barley. The inclusion of oats and wheat starch is controversial. Research supports that oats may be acceptable for patients with celiac disease and can improve the nutritional quality of the diet. However, use of oats is not widely recommended in the United States because of concerns of potential contamination of commercial oats. Studies assessing the contamination of commercial oats are limited. Research indicates no differences in patients choosing a strict wheat starch-containing, gluten-free diet vs. a naturally gluten-free diet. Factors other than trace gluten may be the cause of continued villous atrophy in some patients. The impact of nutrient malabsorption caused from untreated celiac disease is well documented. The diet and gluten-free products are often low in B vitamins, calcium, vitamin D, iron, zinc, magnesium, and fiber. Few gluten-free products are enriched or fortified, adding to the risk of nutrient deficiencies. Patients newly diagnosed or inadequately treated have low bone mineral density, imbalanced macronutrients, low fiber intake, and micronutrient deficiencies. Also troubling is the increased incidence of obesity seen in persons with celiac disease following a gluten-free diet. Because of the nutritional risks associated with celiac disease, a registered dietitian must be part of the health care team that monitors the patient's nutritional status and compliance on a regular basis.