AIM: To comprehensively review and quantitatively summarize results from intervention studies that examined the effects of intact cereal dietary fiber on parameters of bowel function. METHODS: A systematic literature search was conducted using Pub Med and EMBASE. Supplementary literature searches included screening reference lists from relevant studies and reviews. Eligible outcomes were stool wet and dry weight, percentage water in stools, stool frequency and consistency, and total transit time. Weighted regression analyses generated mean change(± SD) in these measures per g/d of dietary fiber. RESULTS: Sixty-five intervention studies among generally healthy populations were identified. A quantitative examination of the effects of non-wheat sources of intact cereal dietary fibers was not possible due to an insufficient number of studies. Weighted regression analyses demonstrated that each extra g/d of wheat fiber increased total stool weight by 3.7 ± 0.09 g/d(P < 0.0001; 95%CI: 3.50-3.84), dry stool weight by 0.75 ± 0.03 g/d(P < 0.0001; 95%CI: 0.69-0.82), and stool frequency by 0.004 ± 0.002 times/d(P = 0.0346; 95%CI: 0.0003-0.0078). Transittime decreased by 0.78 ± 0.13 h per additional g/d(P < 0.0001; 95%CI: 0.53-1.04) of wheat fiber among those with an initial transit time greater than 48 h.CONCLUSION: Wheat dietary fiber, and predominately wheat bran dietary fiber, improves measures of bowel function. AIM: To comprehensively review and quantitatively summarize results from intervention studies that examined the effects of intact cereal dietary fiber on parameters of bowel function. METHODS: A systematic literature search conducted conducted using Pub Med and EMBASE. Supplementary literature searches included screening reference lists from relevant studies and reviews. Eligible outcomes were stool wet and dry weight, percentage water in stools, stool frequency and consistency, and total transit time. Weighted regression analyzes generated mean change (± SD) in these measures per g / d of dietary fiber. : Six quantitative-five intervention studies among generally healthy populations were identified. A quantitative examination of the effects of non-wheat sources of intact cereal dietary fibers was not possible due to an insufficient number of studies. Weighted regression analyzes that each each extra g / d of wheat fiber increased total stool weight by 3.7 ± 0.09 g / d (P <0.0001; 95% CI: 3.50 -3.84), dry stool weight by 0.75 ± 0.03 g / d (P <0.0001; 95% CI: 0.69-0.82) and stool frequency by 0.004 ± 0.002 times / d (P = 0.0346; 95% CI: 0.0003-0.0078 Transittime decreased by 0.78 ± 0.13 h per additional g / d (P <0.0001; 95% CI: 0.53-1.04) of wheat fiber among those with an initial transit time greater than 48 h.CONCLUSION: Wheat dietary fiber, and predominately wheat bran dietary fiber, improves measures of bowel function.