Eligible participants that will be given Ustekinumab as part of their standard of care will be enrolled in this study.~The study hypotheses include that a low serine diet (compared to a high serine diet) in patients with active CD will:~Reduce the relative abundance of Adherent invasive ecoli (AIEC), and increase the relative abundance of Bacteroides and Faecalibacterium in stool of patients with Crohn's disease.~Make patients more likely to respond to ustekinumab (anti-Interleukin12/23) therapy with control of inflammation as measured by the mean Simple endoscopic subscore Crohn's disease (SES-CD) in each group at week 25.
This pilot study is being completed to determine whether a low-serine diet vs a high serine diet will reduce inflammation and symptoms in Crohn's disease (CD), as well as determine whether a low-serine diet (vs. a high serine diet) will improve responses in patients initiating therapy with Ustekinumab (Stelara), an FDA-approved biologic therapy for Crohn's disease.