Background: Some metals and heavy metals are an essential part of the human diet, but some, in high enough doses can result in adverse health effects ranging from runny nose to multi-organ failure. There have been anecdotal reports that a gluten-free diet can result in an increase in arsenic consumption. Only a fraction of individuals that currently adhere to a gluten free diet (GFD) do so for medical reasons, such as celiac disease. Most people chose to go gluten free for a variety of reasons. Aim: To determine if a GFD, or having CD makes a difference in the amounts of certain metal toxins and heavy metals that may occur in gluten free foods. Methods: The NHANES survey is a rigorous sampling of the US population. We have previously determined by questionnaire and serum testing those subjects with celiac disease and those who avoid gluten without a diagnosis of celiac disease. Data base was used to compare the blood and urine levels of predetermined toxic metals in different subsets of the US population. The first comparison determined the differences between individuals on a GFD (N=148) and individuals not on a GFD (16,817). The second comparison was between individuals that were seropositive for CD (tTG-positive, EMApositive) (N=57) and seronegative for CD (tTG-negative, EMA-negative) (N=14,644), followed by a comparison of undiagnosed-CD patients (N=56), non-CD persons who avoid gluten (NCPWAGs)(N=134), and the general U.S. population(N=16,723). The last comparison was between all celiac patients (undiagnosed and diagnosed)(N=68) against non-CD patients (PWAGs and the general population)(N=16,857). Blood laboratory tests that were examined were lead, cadmium, total mercury; urinary laboratory tests examined were total arsenic, cobalt, thallium, strontium, tin, antimony, barium, cadmium, cesium, molybdenum, manganese, lead, tungsten, and uranium. Results: A GFD resulted in increases of blood lead (p<0.0001), blood total mercury (p<0.0001), blood cadmium (p=0.0006), urinary arsenic (p=0.0031), and urinary tin (p=0.0011) as compared to individuals not a gluten free diet. However, there were no differences in tested metal levels between people with and without a gluten free diet. NCPWAGs had almost double the blood lead than undiagnosed celiacs (p<0.0001) and higher levels of blood lead (p<0.0001), blood total mercury (p<0.0001), blood cadmium (p=0.0147), urinary arsenic (p=0.0028), and urinary tin (p= 0.0004) than the general population. Conclusions: These results suggests an association between a GFD and higher levels of blood lead, blood mercury, blood cadmium, urinary arsenic, and urinary tin. It is suggested that individuals on a GFD be monitored for these bioaccumulating metals.