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Dietary fiber is recognized as playing an important role in human health, and research in the field is moving at a fast pace. However, dietary fiber research is complex, and the literature embodies a large number of studies detailing a diverse range of fiber types. Using a systematic literature search and applying pre-defined inclusion/exclusion criteria, we created a database of human intervention studies linking dietary fiber to physiological health outcomes. The final database details 869 unique studies, capturing interventions on over 130 unique fiber types published in English from 1946 to May 2015. To demonstrate a first-hand application of this database, we used it to construct an evidence map on the literature relating dietary fiber to health outcomes on the human gut microbiome. We identified 158 publications in the database examining gut microbiome outcomes, and outcomes were grouped into four broad categories: fermentation (10% of publications with microbiome outcomes), fecal pH (19%), short-chain fatty acid production (31%), and bacterial composition (31%). Oligosaccharides (15%), resistant starch (15%), and cereal fiber (14%) were the most frequently examined fiber types. The majority of studies were crossover designs (65%) in adult populations (99%) with healthy baseline status (82%). Our work on this topic showed that well-controlled human interventions are needed to support associations being observed in animal studies linking fiber-induced changes in the microbiome to health benefits. This database is a valuable resource, allowing researchers to rapidly search the literature and identify research gaps. It may also be a useful starting point for systematic reviews and serve as a resource for food manufacturers, agencies defining fiber for food labeling, and researchers interested in evaluating the health benefits of different fiber sources.