Data for the report was collected from the Korean Genome and Epidemiology study, which analyzed individuals’ scores in the self-reported Dietary Inflammatory Index (DII), a test which quantifies proinflammatory food intake in relation to health outcomes ranging from inflammatory cytokines to chronic diseases.
The study found that higher DII scores, which signified a pro-inflammatory diet, resulted in a 50% higher risk for developing metabolic syndrome in posmenopausal women. Irrespective of menopause, high DII scores were associated with all five facets of metabolic syndrome. While the risks associated with high DII scores were more significant in women, men still saw positive correlations between high DII scores and an increased risk of low HDL cholesterol, elevated waist circumferences, and high blood pressure.
The DII considers diets rich in vegetables, fruits, antioxidants, vitamins, and healthy oils to be low-scoring, since they are generally known to decrease chronic, systemic inflammation, whereas high-scoring diets are rich in fats and simple carbohydrates.
While this study is not the first to associate high DII with metabolic syndrome, it is one of the largest. Many studies prior have examined the role that DII plays in a number of blood inflammatory biomarkers, such as high-sensisitivity C-reactive protein, homocysteine, interleukin-6, and tumor necrosis factor. Additionally, studies have associated DII with cancer, heart disease, and adverse mental health and musculoskeletal disorders.
The strengths of this study were the relatively long follow-up period of about 7.4 year, along with the large sample size which included a significant amount of participants who were not afflicted with metabolic syndrome at baseline.