Prebiotic and Probiotic Modulation of the Gut Microbiota-gut-brain Axis During Acute Stress

Emerging evidence supports the existence of a microbiota-gut-brain axis through which gut microbes influence cognition, mood and behavior. Targeting this axis with probiotics and/or prebiotics may provide novel strategies for mitigating stress-induced decrements in gastrointestinal and cognitive function. This double-blind, placebo-controlled, randomized, parallel-arm trial will determine the effects of a prebiotic and a probiotic dietary intervention on gastrointestinal, cognitive and physiologic responses to acute military-relevant physical and cognitive stress. Healthy men and women will be recruited and randomized to receive a placebo, probiotic or prebiotic for 4wk. Volunteers will be fed a controlled diet during the 4th week of supplementation. Fecal, blood, urine and saliva samples will be collected. Physical stress will be induced by a weighted walk on a treadmill, and will be followed by a cognitively challenging testing scenario that uses intermittent electric shocks to the abdomen to induce a stress response.