The Effect of a Cranberry Beverage on Intestinal Permeability and Gastrointestinal Function in Generally Healthy Adults With a BMI ≥ 30: a Randomized, Double-blind, Controlled, Crossover Study

Obesity, stress, liver disease, alcoholism, diabetes, and autoimmune diseases in humans or animal models are associated with altered intestinal permeability; consequently, maintenance of the gastrointestinal barrier is an emerging area of interest. The purpose of this randomized, double-blind, controlled crossover study is to compare the difference between the change from baseline in gastroduodenal permeability after drinking a cranberry or control beverage for two weeks. Gastroduodenal permeability will be assessed following aspirin challenge by measuring urinary sucrose in the 0 to 5-hour urine collection after differential sugar probes are consumed. Urine will be collected for an additional 19 hours (24 hours total) to assess whole gut permeability. A 4-week washout period will separate the interventions. Stool and fasting blood and saliva samples will be obtained before and during the intervention periods to assess fecal microbial communities and markers of intestinal barrier, immune function and oxidative stress. It is anticipated that cranberry juice will selectively increase intestinal Akkermansia bacteria, reduce markers of inflammation and oxidative stress, increase mucosal immunity, and protect the gastroduodenal barrier from an aspirin challenge.