Analysis of 1999–2017 NHANES Data: Minimal Increase and Racial Disparities in U.S. Fiber Consumption Over 18 Years

Abstract

Low dietary fiber consumption is associated with an increased risk of colorectal cancer, a leading cause of cancer-related mortality in the United States. The average daily fiber intake has declined over recent decades. Notably, Black Americans exhibit lower fiber consumption than other racial/ethnic groups, possibly influencing their elevated colorectal cancer rates. We hypothesize that there has been a significant increase in dietary fiber consumption in the United States from 1999 to 2017. The study encompassed 59,204 adult NHANES participants and observed variations in caloric intake over survey years. Although there was a slight overall increase in dietary fiber intake compared to 1999, the most substantial increment occurred among individuals classified as Hispanic (AD: +2.86 g, P < 0.001), followed by non-Hispanic Black (AD: +1.64 g, P < 0.001), and finally non-Hispanic White showed a decrease in fiber intake (AD: −0.86 g, P < 0.001). The findings suggest a modest rise in fiber consumption from 1999 to 2017, but disparities persist, particularly with non-Hispanic Black individuals consuming the least fiber. This emphasizes the need for interventions to promote fiber intake and address racial/ethnic inequalities in dietary habits.