Association between dietary inflammatory index and cardiometabolic risk factors among Brazilian adolescents: results from a national cross-sectional study

The dietary inflammatory index is positively associated with insulin resistance in underweight and healthy weight adults

The aim of this study was to explore the relationship between dietary inflammatory index (DII) and insulin resistance (IR) in underweight and healthy weight adults. This cross-sectional study involved 3205 participants from the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2018. All dietary data used to calculate the DII were obtained based on the average of two 24-h dietary recall interviews. Participants were divided into an anti-inflammatory diet group and a pro-inflammatory diet group based on DII < 0 and DII ≥ 0, respectively. Fasting blood glucose and fasting insulin data used to calculate IR index (HOMA-IR) were from laboratory data in the NHANES database. According to the linear regression analysis results of DII and HOMA-IR, we found that there was a positive relationship between DII and IR. A positive association between DII and HOMA-IR was seen in the following groups after stratification: by age in 20-39-year olds, by sex in males, by race in Non-Hispanic Whites, by family history of diabetes in those without a family history of diabetes, by education level in those with high school education, by smoking status in current smokers and non-smokers, by hypertension in those with hypertension, by BMI in those with a BMI of 18.5-24.99, by hypertriglyceridemia (HTG) in those without HTG, by poverty impact ratio (PIR) in those with PIR ≤ 1.3 and >1.3, and by physical activity in those with moderate recreational activities. In conclusion, in underweight and healthy weight adults, DII was positively correlated with the risk of IR.

Obesity, Cardiovascular and Neurodegenerative Diseases: Potential Common Mechanisms

The worldwide increase in the incidence of obesity and cardiovascular and neurodegenerative diseases, e.g. Alzheimer's disease, is related to many factors, including an unhealthy lifestyle and aging populations. However, the interconnection between these diseases is not entirely clear, and it is unknown whether common mechanisms underlie these conditions. Moreover, there are currently no fully effective therapies for obesity and neurodegeneration. While there has been extensive research in preclinical models addressing these issues, the experimental findings have not been translated to the clinic. Another challenge relates to the time of onset of individual diseases, which may not be easily identified, since there are no specific indicators or biomarkers that define disease onset. Hence knowing when to commence preventive treatment is unclear. This is especially pertinent in neurodegenerative diseases, where the onset of the disease may be subtle and occur decades before the signs and symptoms manifest. In metabolic and cardiovascular disorders, the risk may occur in-utero, in line with the concept of fetal programming. This review provides a brief overview of the link between obesity, cardiovascular and neurodegenerative diseases and discusses potential common mechanisms including the role of the gut microbiome.

Dietary inflammatory index and its relation to the pathophysiological aspects of obesity: a narrative review

Obesity, a complex disease that involves energy imbalance and chronic low-grade inflammation, is implicated in the pathogenesis of several chronic non-communicable diseases. As dietary components modulate the human body's inflammatory status, the Dietary Inflammatory Index (DII®), a literature-derived dietary index, was developed in 2009 to characterize the inflammatory potential of a habitual diet. Abundant research has been conducted to investigate the associations between DII and obesity. In this narrative review, we examined the current state of the science regarding the relationships between DII and the inflammatory pathophysiological aspects related to obesity. DII is associated with inflammation in obesity. The most pro-inflammatory diet was directly related to higher levels of pro-inflammatory markers, which included C-reactive protein (CRP), interleukin-6 (IL-6), IL-1β, and tumor necrosis factor-α (TNF-α). Therefore, evidence suggests that the use of the DII may be useful for understanding the relationship between diet and the inflammatory process related to obesity.

Dietary Inflammatory Index and Cardiometabolic Risk in Ecuadorian School-Age Children

BACKGROUND

Cardiometabolic diseases and metabolic syndrome (MetS) are becoming increasingly prevalent in low- and middle-income countries (LMICs). Cardiometabolic diseases and MetS are closely associated with low-grade systemic inflammation, which may be modified by diet. Previous studies have focused on the association of dietary inflammation with MetS and cardiometabolic risk in adult populations, but few studies have examined this issue in children, especially in LMICs.

METHODS

We conducted a cross-sectional study to explore the association of dietary inflammation with cardiometabolic risk components and MetS in urban Ecuadorian children aged 6-12 years old (n = 276). A semi-quantitative food frequency questionnaire (FFQ) was used to collect data on child dietary intake. Dietary inflammation was evaluated using an energy-adjusted Dietary Inflammatory Index (DII), divided into quartiles. Data were also collected on cardiometabolic risk indicators including blood lipids, blood pressure (BP), blood glucose, body mass index, and waist circumference. Data were analyzed using multivariable linear and logistic regression.

RESULTS

Child DII scores ranged from -4.87 (most anti-inflammatory) to 4.75 (most pro-inflammatory). We transformed the continuous scores into quartiles (Q): Q1 was the most anti-inflammatory (-4.87 to -3.35), Q2 was anti-inflammatory (-3.34 to -1.45), Q3 was pro-inflammatory (-1.44 to 1.08), and Q4 was the most pro-inflammatory (1.09 to 4.75). In the covariate-adjusted model, DII scores were positively associated with total blood cholesterol (p = 0.027), triglycerides (p = 0.034), and diastolic BP (p = 0.013). In addition, for every one-unit increase in DII score, MetS increased by 1.20 in the covariate-adjusted model (95% CI = 1.01,1.43).

CONCLUSIONS

The findings suggest that more pro-inflammatory diets may contribute to poorer cardiometabolic health in school-age children. This is important because even small increases in child blood pressure, blood cholesterol, and glucose levels over time can damage health and lead to earlier progression to conditions such as hypertension and atherosclerosis.