S817 Trend of Mean Dietary Fiber Intake by Insurance Status Across Cycles (2017–2020 vs 2021–2023) Based on NHANES

Introduction: Colorectal cancer (CRC) remains one of the leading causes of cancer-related morbidity and mortality worldwide. While nonmodifiable risk factors—such as age, family history, and genetic syndromes—play a role, accumulating evidence highlights the profound impact of modifiable lifestyle choices, particularly diet, on CRC risk. Among dietary factors, fiber intake has garnered significant attention: diets rich in fiber not only support general gastrointestinal health but also confer a protective effect against CRC. Methods: We utilized NHANES database from 2017-2020 and 2021-2023 to analyze dietary fiber data. Data on demographics and insurance was also obtained. Python coding software was utilized for analysis of trends in dietary fiber intake. Results: Insured participants (n = 7123) had a higher average fiber intake (17.3 g/day) than uninsured participants (n = 1325; 15.0 g/day). Among insured adults, females averaged 17.6 g/day versus males at 16.9 g/day. Among uninsured adults, females averaged 15.2 g/day versus males at 14.8 g/day. Insured Non-Hispanic Asians had the highest mean fiber intake (18.8 g/day), followed by Non-Hispanic Whites (17.9 g/day). Uninsured Non-Hispanic Asians also had relatively higher intake (16.9 g/day), but all uninsured groups tended to cluster around 14–16 g/day. Both insured and uninsured groups showed a slight uptick in mean fiber intake from the 2017–2020 cycle to the 2021–2023 cycle, but insured adults consistently consumed more fiber than uninsured in both cycles. Conclusion: Dietary fiber refers to the nondigestible carbohydrates found in plant-based foods—namely, whole grains, legumes, fruits, and vegetables. Mechanistically, fiber reduces CRC risk by accelerating intestinal transit time, thereby minimizing the duration of contact between potential carcinogens and the colonic mucosa. Furthermore, fermentation of soluble fiber by gut microbiota generates short-chain fatty acids such as butyrate, which exhibit anti-inflammatory and pro-apoptotic effects on colonic epithelial cells. Insurance coverage indicates higher fiber intake overall.