This is dietary intervention trial that will examine the impact of consuming three different types of resistant starch on the gut microbiome and butyrate levels in normal weight and obese individuals. Participants will consume starch samples daily for 24 weeks, collecting weekly fecal samples that will be returned to the lab. Researchers will analyze the bacterial fermentation products in these samples, particularly butyrate and analyze the microbiome composition. This will allow identification of differences in resistant starch (a dietary fiber) processing between normal weight and obese individuals and will also determine if the three resistant starches tested have differing impacts on the microbiome and butyrate levels.