The Influence of Diet Interventions Using Whole, Plant Food on the Gut Microbiome: A Narrative Review

Dietary intake is a key determinant of gastrointestinal microbiota composition. Studies have considered the relationship between gut microbiota and dietary patterns. It is likely that certain plant foods that contain fiber and other bioactive matter may be more likely to drive microbial changes than others; however, study design and other factors can make interpretation of the literature difficult. Fifteen well-controlled, well-defined diet interventions published between 2008 and 2018 using whole, plant foods were evaluated for their influence on gut microbiota. There was limited effect on microbial diversity across studies and modest microbial changes were noted in 10 of 15 studies. More research is needed before specific plant foods can be recommended to improve gut microbiota and ultimately health. Methodologic considerations for future diet and microbiome studies are discussed. Additional research to better understand how specific whole, plant foods influence microbe composition, functionality, and metabolite production is needed, as are mechanistic studies linking diet-induced gut microbe changes to health.