biostudies-literatureReznikov EANational Institute of Environmental Health SciencesNIEHS NIH HHS115773https://www.ebi.ac.uk/biostudies/studies/S-EPMC12640686biostudies-literatureUnknown207Exclusive Enteral Nutrition (EEN) can induce remission in Crohn's disease (CD). We completed a pilot study using novel reverse-engineered EEN (RE-EEN), a whole food smoothie in place of commercial liquid formula (EEN) which contains food additives to improve shelf stability and palatability. In a four week trial with RE-EEN, we reported 80 % of patients went into clinical remission after four weeks. We hypothesized RE-EEN would decrease environmental toxin exposure through reduction of processing food intake. Biosamples were collected at baseline and at weeks two, four, and eight during the RE-EEN study. Urinary heavy metals were analyzed by inductively coupled plasma mass spectrometry, and urinary phthalate metabolites and melamine by liquid chromatography with tandem mass spectrometry. For our primary analysis, change in baseline was calculated using a paired t-test for week four. Analysis was also completed for all weeks on RE-EEN using a generalized least squares model. Results were expressed as fold change ± standard error mean. Paired t-testing demonstrated a statistically significant (p < 0.05) effect on molybdenum (Mo) with a fold change of 0.17 ± 0.15, an 83 % reduction following RE-EEN treatment. Our results suggested an effect of arsenic (As) with fold change of 0.23 ± 0.26 (p = 0.12), a 77 % reduction following RE-EEN treatment. Our results also suggested an effect of cobalt (Co) with a fold change of 3.12 ± 3.12 fold, a 212 % increase following RE-EEN therapy (p = 0.16). With inclusion of all weeks on RE-EEN, Mo and As were statistically significant (p < 0.05). Overall, we observed favorable shifts in urinary heavy metals by week four, and no effects were suggested in phthalate and melamine analysis. We saw increased precision in a sensitivity analysis when including all weeks for treatment. This is the first study to examine environmental toxicants in relation to whole foods smoothie diet in pediatric CD. RE-EEN dietary intervention shows promise in reducing chemical exposures and may contribute to CD remission. Notable limitations to this research include small sample size and absence of a control group. Further studies are necessary to assess the impact of RE-EEN diet on environmental toxicant exposure.Food and chemical toxicology : an international journal published for the British Industrial Biological Research AssociationReverse-engineered exclusive enteral nutrition as induction therapy in pediatric Crohn's disease: Effects on environmental toxin exposure.PMC12640686P30 ES007033K12 ES033584P30ES0070335K12ES033584Sathyanarayana SSamy SSuskind DLLee DYMacDonald JReznikov EAMelough MMBammler TKfalseReverse-engineered exclusive enteral nutrition as induction therapy in pediatric Crohn's disease: Effects on environmental toxin exposure.Exclusive Enteral Nutrition (EEN) can induce remission in Crohn's disease (CD). We completed a pilot study using novel reverse-engineered EEN (RE-EEN), a whole food smoothie in place of commercial liquid formula (EEN) which contains food additives to improve shelf stability and palatability. In a four week trial with RE-EEN, we reported 80 % of patients went into clinical remission after four weeks. We hypothesized RE-EEN would decrease environmental toxin exposure through reduction of processing food intake. Biosamples were collected at baseline and at weeks two, four, and eight during the RE-EEN study. Urinary heavy metals were analyzed by inductively coupled plasma mass spectrometry, and urinary phthalate metabolites and melamine by liquid chromatography with tandem mass spectrometry. For our primary analysis, change in baseline was calculated using a paired t-test for week four. Analysis was also completed for all weeks on RE-EEN using a generalized least squares model. Results were expressed as fold change ± standard error mean. Paired t-testing demonstrated a statistically significant (p < 0.05) effect on molybdenum (Mo) with a fold change of 0.17 ± 0.15, an 83 % reduction following RE-EEN treatment. Our results suggested an effect of arsenic (As) with fold change of 0.23 ± 0.26 (p = 0.12), a 77 % reduction following RE-EEN treatment. Our results also suggested an effect of cobalt (Co) with a fold change of 3.12 ± 3.12 fold, a 212 % increase following RE-EEN therapy (p = 0.16). With inclusion of all weeks on RE-EEN, Mo and As were statistically significant (p < 0.05). Overall, we observed favorable shifts in urinary heavy metals by week four, and no effects were suggested in phthalate and melamine analysis. We saw increased precision in a sensitivity analysis when including all weeks for treatment. This is the first study to examine environmental toxicants in relation to whole foods smoothie diet in pediatric CD. RE-EEN dietary intervention shows promise in reducing chemical exposures and may contribute to CD remission. Notable limitations to this research include small sample size and absence of a control group. Further studies are necessary to assess the impact of RE-EEN diet on environmental toxicant exposure.2026-01-01T00:00:00Z2026 Jan2026-07-05T03:11:56.786Z2026-07-05T03:08:27.596ZS-EPMC126406864103837310.1016/j.fct.2025.115773