Table 1.

Reviews on nutrient deficiencies in celiac patients at time of diagnosis and after GFD.

Authors	Type of Study	Country and Year	Results
[2]	Review	Italy, 2010	Common nutrient deficiencies in celiac subjects at diagnosis are: iron, calcium, magnesium, vitamin D, zinc, folate, niacin, vitamin B12, riboflavin, calorie/protein, and fiber. Deficiencies in folate, niacin, and vitamin B12 may occur after LTGFD.
[9]	Review	Italy, 2016	Low levels of fibers, folate, vitamin B12, vitamin D, calcium, iron, zinc and magnesium are common at diagnosis stage. In some subsets of treated celiac disease (CD) patients they can persist.
[16]	Review	USA, 2005	Deficiencies in fiber, iron, calcium, vitamin D, magnesium, zinc, folate, niacin, vitamin B12, and riboflavin can occur at time of diagnosis. Deficiencies in fiber, iron, calcium, vitamin D, and magnesium can persist after following a GFD. Diet and gluten-free products are often low in B vitamins, calcium, vitamin D, iron, zinc, magnesium, and fiber.
[17]	Review	Italy, 2013	Reduced levels of iron, folate, vitamin B12, and vitamin D are common at the time of diagnosis. After GFD low levels of folate, vitamin B12 and vitamin D can persist.
[18]	Review	Italy, 2013	Common deficiencies at diagnosis include: fiber, iron, calcium, vitamin D, magnesium, zinc, folate, niacin, and vitamin B12. Deficiencies of fiber, iron, calcium, vitamin D, magnesium, zinc, folate, niacin, vitamin B12 may persist after following a GFD. Deficiencies of fiber, folate, niacin, vitamin B12, and riboflavin may persist after LTGFD.