Association between Patterns of Dietary Habits and Obesity in Iranian Adults

Findings from few studies that investigated the relation between dietary behaviors and obesity are inconsistent. We aimed to assess the relation between patterns of dietary habits, identified by latent class analysis (LCA) and obesity in a large sample of Iranian adults.
In a cross-sectional study on 7958 adults, dietary behaviors were assessed in five domains (meal patterns, eating rate, intra-meal fluid intake, meal-to-sleep interval and fatty foods intake) using a pretested questionnaire. LCA was applied to identify classes of diet-related practices. Anthropometric measures were assessed through the use of a validated self-reported questionnaire. General and abdominal obesities were defined as a body mass index ≥30 kg/m2 and a waist circumference ≥88 cm for women, ≥102 cm for men.
General and abdominal obesityies were prevalent in 9.7 and 27.7% of the study population, respectively. We identified three distinct classes of eating rates (moderate, moderate-to-slow and moderate-to-fast), two classes of meal patterns (­regular and irregular), two classes of intra-meal fluid intake (moderate and much intra-meal drinking), three classes of meal-to-sleep interval (short, moderate and long meal-to-sleep interval), and three classes of fatty foods intake (low, moderate and high intake of fatty foods). After adjustment for potential confounders, individuals with ‘irregular meal pattern’ were 21%, 24% and 22%, respectively more likely to be overweight/obese, abdominally overweight/obese and abdominally obese, compared with those who had a ‘regular meal pattern’. Individuals with ‘much intra-meal drinking’ had greater odds of overweight (OR: 1.37; 1.19-1.58) and obesity (OR: 1.51; 1.16-1.97) than those with ‘moderate intra-meal drinking’. Moderate intake of fatty foods was inversely associated with abdominally overweight/obese (OR: 0.85; 0.73-1.00) and abdominally obesity (OR: 0.80; 0.68-0.96) compared with ‘low intake of fatty foods’. No significant association was observed between eating rate, meal-to-sleep interval and general or abdominal obesity, after controlling for confounders.
Irregular meal pattern and much intra-meal drinking were associated with increased odds of general and abdominal obesities, whereas moderate intake of fatty foods was related to the decreased odds of central obesity among Iranian adults.