Greater cumulative exposure to a pro‐inflammatory diet is associated with higher metabolic syndrome score and blood pressure in young Mexican adults

Abstract

Low-grade inflammation is a suggested mechanism in the development of metabolic syndrome (MetS), and diet could act as a regulator. Therefore, we hypothesized that the cumulative Dietary Inflammatory Index (DII®) exposure from diet during infancy through adulthood would be positively associated with the MetS and its components in young Mexican adults. One hundred participants from the Early Life Exposures in Mexico to Environmental Toxicants cohort were included in this analysis. The dietary inflammatory potential of the diet (without supplements) was assessed using 27 nutrients obtained from repeated food frequency questionnaires (1-22 years) using the DII, a validated score. The cumulative exposure of DII was constructed using the area under the curve (AUC of DII). The MetS was defined using the International Diabetes Federation criteria, and the Metabolic Syndrome Risk Z-score (MetRisk Z-score) was estimated. Linear regressions were conducted to assess the association between the AUC of DII with MetRisk Z-score and MetS components, adjusting for sex, socioeconomic status, smoking status, physical activity, birth weight, and body mass index. In adulthood, the mean age was 21.5 years, 54% were male, and 17% had MetS. Positive associations were found between AUC of DII with MetRisk Z-score (β = .12; 95% confidence interval [CI]: 0.03-0.22; P = .009) and systolic (β = .33; 95% CI: 0.05-0.61; P = .023) and diastolic blood pressure (β = .24; 95% CI: 0.01-0.47; P = .040). A cumulative proinflammatory diet from infancy through young adulthood is associated with higher MetRisk Z-scores as well as blood pressure. These findings may provide evidence for the implementation of anti-inflammatory diet interventions throughout early life for the prevention of cardiometabolic risk.

Introduction

Metabolic syndrome (MetS) is defined as a cluster of cardiometabolic risk factors, including abdominal obesity, hyperglycemia, dyslipidemia, and elevated blood pressure [1]. Subjects with MetS have an increased risk for the development of type 2 diabetes and cardiovascular disease [2].

MetS is considered a public health problem with increasing prevalence on a global scale [3]. According to the International Diabetes Federation (IDF), it is estimated that 25% of the world’s population has MetS [4]. In Mexico, the 2006 National Health and Nutrition Survey reported a national prevalence of MetS of 26% in the group of young adults (20-29 years) [5]. The prevalence of early-onset MetS has increased in parallel with the incidence of obesity in Mexico [6].

Evidence suggests that MetS pathology could, in part, be a consequence of a low-grade systemic inflammatory process, determined by an elevation of cytokines with proinflammatory activity [7]. Diet is a modifiable factor that has an important role as a regulator of the balance between pro- and anti-inflammatory cytokines [8]. Unhealthy dietary patterns (high intake of fat, refined carbohydrates, and proteins) have been associated with higher levels of inflammation, whereas healthier diets (high content of fruits, vegetables, and fish) have been linked to lower inflammation in adults [9].

The Dietary Inflammatory Index (DII) estimates the inflammatory potential of the diet based on the association between dietary components and biomarkers involved in inflammation [10]. Several studies have evaluated the association of DII with MetS in adults. Two cross-sectional studies in Korean and Iranian populations found positive associations of DII with MetS [11,12]. In contrast, 2 other cross-sectional studies in Polish and American adults observed associations only with some of the individual MetS components, such as glucose, diastolic blood pressure, and waist circumference (WC) [[13], [14], [15]]. From 2 longitudinal studies in Europe that evaluated the lifetime association between DII and MetS, only 1 found that more proinflammatory diets were associated with the diagnosis of MetS and with some of its components (triglycerides [TG], high-density lipoprotein cholesterol [HDL-C], and systolic [SBP] and diastolic blood pressure [DBP]) [15,16].

In Mexico, only 1 previous cross-sectional study has evaluated the DII with health outcomes in the adult population, finding that subjects in the highest quintile of the DII had higher odds of type 2 diabetes mellitus [17]. To our knowledge, there are no previous studies that have evaluated the role of DII exposure during childhood and adolescence with MetS risk in young Mexican adults. The first years of adult life are crucial for identifying and targeting cardiometabolic risk factors, and in the context of the high prevalence of MetS in Mexico, the objective of the present study was to evaluate the association between the cumulative exposure (from ages 1 to 21-22 years) to a proinflammatory diet with MetS and its components in young Mexican adults.

We hypothesized that a greater cumulative proinflammatory diet from infancy through adulthood would be positively associated with the MetS score and its components in this population. First, to evaluate the inflammatory potential of diet during childhood, we calculated the area under the curve (AUC) of the DII at each childhood visit. Second, we explored the association of the cumulative DII and the metabolic risk syndrome, with multiple linear regressions.