Background

Over the past two decades, China has experienced unprecedented rapid modernization, dramatic and rapid increases in obesity, and major changes in diet and physical-activity behaviors. Past studies on fat intake and overweight and obesity have been controversial. The purpose of this study was to examine the impacts of high-fat diet on body weight and the risk of overweight and obesity in China.

Methods

We examined the impacts of fat intake on overweight and obesity using data from 65,029 observations of 23,859 adults aged 20–60 years who participated in the China Health and Nutrition Survey (CHNS), an ongoing, open-cohort study covering twelve provinces and municipal cities across ten waves of data from 1991 to 2015. We collected detailed dietary data by using three 24-hour recalls combined with weighing of foods and condiments in household inventories. We estimated the association between fat intake and body weight, body mass index (BMI), and the risk of overweight and obesity with random-effects regression or logit models for panel data, stratified by sex.

Results

Over twenty-five years, fat intake, energy from fat, and high-fat diet (defined as energy from fat > 30%) increased from 68.5 grams/day (g/d), 23.1%, and 22.4% in 1991 to 79.3 g/d, 35.6%, and 67.2% in 2015, respectively. The prevalence of overweight and obesity (defined as BMI ≥ 25 kg/m2) increased from 12.3% to 37.3% during the same period. When controlling for energy intake from non-fat, physical activities, and other variables of socioeconomic status, fat intake, energy from fat, and high-fat diet significantly increased body weight, BMI, and the risk of overweight and obesity in both sexes.

Conclusions

High fat intake or high energy from fat increased body weight, BMI, and the risk of overweight and obesity. These findings may have significant impacts on policies and interventions related to controlling overweight and obesity.