Association between dietary inflammation index with anemia in Americans: a cross-sectional study with US National health and nutrition examination survey

Objectives: Dietary inflammatory index (DII) is utilized to determine the inflammatory effects of nutrients and foods on various diseases. Inflammation is a potential risk factor for anemia. We hypothesize that pro-inflammatory diets boost the incidence of anemia, as indicated by high DII. Methods: 41, 360 Americans were included in this study from the U.S. National Health and Nutrition Survey (NHANES) from 2003-2018. Multivariable logistic regression models were employed to examine the association between DII and anemia. Results: After adjustment for all the covariates, the odds ratios (ORs) (95% CI) between the risk of anemia and DII across tertile 3 were 1.2556 (95% CI 1.0621, 1.4843; P = 0.0077), and the trend test was statistically significant (P for trend = 0.009). Furthermore, in the subgroup analysis stratified by gender. The ORs (95% CI) between the risk of anemia and DII across tertile 2 and 3 were 1.8071 (95% CI 1.1754, 2.7783; P = 0.0070) and 2.1591 (95% CI 1.4009, 3.3278; P = 0.0005) in men after multivariable adjustment. However, in women, this association was only significantly different (P < 0.05) across tertile 3 in the crude model. In the subgroup analysis stratified by race, this association was significant (P < 0.05) between the risk of anemia and DII for Non-Hispanic Whites/Blacks after adjustment. Discussion: Together, anemia was significantly associated with DII using logistic regression. In stratified analyses, higher DII scores were linked to an increased incidence of anemia in men, while no association was found in women after adjustment. Additionally, anemia may be associated with greater pro-inflammatory diets in Non-Hispanic Whites/Blacks. Conclusion: In the present study, we evaluate the potential relationship between DII and anemia using data from NHANES. This cross-sectional study confirmed the hypothesis that the higher DII was significantly associated with a higher risk of anemia in the U.S. population.