Association between Phytate Intake and C-Reactive Protein Concentration among People with Overweight or Obesity: A Cross-Sectional Study Using NHANES 2009/2010

Phytic acid has anti-oxidant properties, which are useful in addressing inflammation. This study investigated the relationship between dietary phytate intake and C-reactive protein (CRP) levels among individuals that are overweight or obese. The study used cross-sectional data from the 2009/2010 National Health and Nutrition Examination Survey (NHANES) for 3152 subjects. Phytate intake was estimated using phytate content of foods reported by the International Zinc Nutrition Consultative Group (IZiNCG). Logistic regression was used to determine the associations between phytate intake and odds of elevated CRP concentration (CRP >3 mg/L), adjusting for confounders. Medians (and 95% CIs) for phytate intake and CRP concentration were 0.66 (0.64, 0.68) g/d and 1.4 (1.2, 1.5) mg/L, respectively. Phytate intake was higher in males than females, higher in non-Hispanic Whites than non-Hispanic Blacks and Mexican Americans, and lower in current smokers than former smokers and nonsmokers. Higher phytate intake was associated with lower odds of elevated CRP (OR = 0.66; 95% CI = 0.52, 0.84). Women, as well as current and former smokers with overweight or obesity, had higher odds of elevated CRP concentration. These results imply that individuals with high phytate intake, particularly among those with overweight or obesity, have lower risk for inflammation-related chronic diseases such as cardiovascular diseases.