SCFAs function as an energy source and decrease the colonic pH, thereby promoting the growth of beneficial bacteria, such as Bifidobacteria and Lactobacilli. These bacteria can interact with the host immune system, produce certain vitamins in the lumen, and promote gut architecture and function development. Moreover, propionate has been shown to inhibit the synthesis of liver cholesterol. Fibers can directly interfere with lipid absorption by changing the luminal solubility and the digestive processes. Pea fiber and wheat bran fiber are increasingly incorporated into human food and animal diets as DF ingredients. Previous studies have shown that wheat bran, a by-product generated in large amounts during wheat processing, is a concentrated source of insoluble fiber, in which 46% is NSP. The main NSPs present are arabinoxylan, cellulose, and b-glucan.Wheat bran has shown antioxidant activities in vitro. Some studies indicate that WF VE-821 decreases fecal bile acid concentration and blood glucose and cholesterol levels in type 2 diabetic patients. PF may be an interesting DF source because PF is white, has good palatability, has high insoluble fiber, and has granulated powder that is easily baked into bread and meat. The postprandial blood glucose response is markedly reduced by PF. Pea has been shown to lower serum cholesterol levels. Moreover, PF does not significantly alter the excretion of total bile acids, but decreases the concentration of fecal total bile acids. The exact mechanisms by which PF and WF contribute to various health conditions are still not fully understood. Therefore, the health effects of PF and WF consumption and knowledge of these mechanisms need to be elucidated. Recent LEE011 metabolomics studies reveal the effects of exposure to whole grain wheat flours and to sweet potato fiber in the endogenous metabolism of rats. Rye fiber supplementation can alter the urine and plasma metabolome in pigs. Moreover, the difference of the plasma metabolic profiles between low fiber and high fiber is shown in humans. Thus, metabolomics can be considered an emerging and promising science with a level of information that spans the traditional approach for elucidating the biochemical response to diet and unrecognized mechanisms. However, no studies are available on the response of animal or human biological systems to PF supplementation, and few studies have focused on the response of animal or human biological systems to WF supplementation. The rat model used has been shown to correlate with human studies. These profiles provide evidence on the relationship between metabolites and nutritional biochemical mechanisms of PF and WF supplementation and establish the baseline data for future metabolomic studies. This approach is potentially useful to investigate PF and WF metabolism and verifies the association between PF and WF administration and health or disease risk.