Food-based indexes and their association with dietary inflammation

Chronic inflammation is associated with an increased risk of noncommunicable diseases, prompting an intensified interest in the diet-disease relationship for modulating inflammation. Diet quality indexes are widely used to quantify dietary patterns. However, the optimal tool for assessing dietary quality in relation to chronic inflammation remains unclear. The objective of this study was to synthesize the literature on food-based diet quality indexes and their association with chronic inflammation. A systematic scoping review of scientific databases was conducted from inception to March 2024. Studies describing the development and validation of original dietary inflammatory indexes or assessed associations between established indexes and inflammatory biomarkers were included. Studies that predominantly focused on nutrient-based indexes were excluded. Forty-three food-based indexes, evaluated across 65 studies, were categorized into 4 distinct groups based on dietary patterns (n = 18), dietary guidelines (n = 14), dietary inflammatory potential (n = 6), and therapeutic diets (n = 5). Established indexes based on the Mediterranean diet and dietary guidelines were the most extensively utilized, demonstrating inverse associations with several inflammatory biomarkers across diverse populations. The Anti-Inflammatory Diet Index, Dietary Inflammation Score, and Empirical Dietary Inflammatory Index were identified as robust, empirically derived indexes to assess diet quality based on their inflammatory potential. The dietary composition of the evaluated indexes ranged from 4 to 28 dietary components, with fruits, vegetables, whole grains, and legumes consistently classified as favorable, whereas red/processed meats and added sugars were unfavorable. This scoping review identified several promising food-based indexes for assessing inflammation-related diet quality. Methodological variations and inconsistencies in algorithms underscore the need for further validation across diverse populations. Future research should consider the scoring methods, dietary composition, and validated inflammatory biomarkers when selecting indexes to evaluate diet-inflammation associations. Understanding the characteristics that underpin these indexes informs their application in nutrition research and clinical practice.