Associations among diet, inflammation and iron status in young adults

UNCG Author/Contributor (non-UNCG co-authors, if there are any, appear on document)
Jeanne L. Doherty (Creator)
Institution
The University of North Carolina at Greensboro (UNCG )
Web Site: http://library.uncg.edu/
Advisor
Seth Armah

Abstract: Obesity is a risk factor for poor iron status due to the chronic, low-grade inflammation of adipose tissue hypertrophy. Among other positive acute phase proteins, the hepatic peptide hormone hepcidin is secreted during inflammation, inhibiting systemic iron efflux from enterocytes and downregulating systemic iron recycling by suppressing iron release from the mononuclear phagocyte system. Conversely, production and secretion of the iron transport protein transferrin by the liver is reduced during inflammation. In addition to increasing adiposity, certain foods are also known to promote inflammatory states and may contribute to these same effects in concert with, or independent of obesity. In this study, we evaluated how inflammatory diets are related to inflammatory and iron status biomarkers among 98 young adults with normal weight, overweight and obesity. Three-day dietary records and biomarker data for iron status and inflammation from two cross-sectional studies of similar design (Diet and Inflammation Study, n= 39 and the Selenium and Inflammation Study, n= 59) were used in this study. Dietary Inflammatory Index (DII) scores were calculated for each subject using nutrients and other dietary components from the dietary records, and subjects were further classified into two DII categories using cluster analysis. Using ANOVA we compared iron status and inflammatory markers among subjects with normal weight, overweight and obesity. We determined the association between DII scores or DII category and C-reactive protein (CRP), hepcidin, serum iron and total iron binding capacity (TIBC). Statistical significance was set at P< 0.05. Mean + SEM were reported for continuous variables except for skewed variables in which case geometric means (geometric mean +1SEM interval) were reported. CRP concentration differed significantly by BMI category (p < 0.05 for all comparisons) and serum iron (SI) was lower in the obese category compared to normal weight (p=0.014). Results from the regression analysis showed that high DII scores were associated with increased CRP concentration and decreasing TIBC. Similarly, subjects in the anti-inflammatory diet group showed higher TIBC compared to those in the inflammatory diet group. In conclusion, our study showed that inflammatory diets may impair iron status by reducing the capacity of the iron transport protein transferrin to transport iron in the blood.

Additional Information

Publication
Thesis
Language: English
Date: 2019
Keywords
C-reactive protein, Dietary Inflammatory Index, Inflammation, Iron Deficiency, Total Iron Binding Capacity, Young Adults
Subjects
Inflammation
Iron in the body
Diet
C-reactive protein

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