Toward a quantitative theory of food consumption choices and body weight

A sales tax is better at promoting healthy diets than the fat tax and the thin subsidy

We analyze how a sales tax levied on all food products impacts the consumption of healthy food, unhealthy food, and obesity. The sales tax can stimulate the consumption of healthy meals by lowering the time costs of food preparation. Moreover, the sales tax lowers obesity under more general conditions than a tax on unhealthy food (fat tax) and a subsidy on healthy food (thin subsidy). We calibrate the model using recent consumption and time use data from the US. The thin subsidy is counterproductive and increases weight. While both the sales tax and the fat tax mitigate obesity, the former imposes a lower excess burden on consumers.

Long-run overweight levels and convergence in body mass index

We evaluate the hypothesis of convergence to an optimal long-run body weight worldwide. We formulate a simple rational non-addiction eating model to derive a testable equation that allows us to verify the existence of a long-run body weight as well as its estimation. We use a database of body mass index (BMI) estimates across countries over four decades published by the NCD Risk Factor Collaboration. We find that BMIs converge among European countries but not in the rest of the world. Consistent with the theoretical model, our long-run estimates suggest that European nations will show an average BMI above healthy levels. In particular, females and males will show average BMIs classified as overweight levels (BMI = 28.3). Confidence intervals and sensitivity analysis suggest that males might reach long-term BMI levels associated with obesity (BMI > 30). We discuss the implications of our findings from the perspectives of health economics and economic development.

Gender difference in the association between food away-from-home consumption and body weight outcomes among Chinese adults

Objective

The present study aimed to explore the associations between food away-from-home (FAFH) consumption and body weight outcomes among Chinese adults.

Design

FAFH was defined as food prepared at restaurants and the percentage of energy from FAFH was calculated. Measured BMI and waist circumference (WC) were used as body weight outcomes. Quantile regression models for BMI and WC were performed separately by gender.

Setting

Information on demographic, socio-economic, diet and health parameters at individual, household and community levels was collected in twelve provinces of China.

Subjects

A cross-sectional sample of 7738 non-pregnant individuals aged 18–60 years from the China Health and Nutrition Survey 2011 was analysed.

Results

For males, quantile regression models showed that percentage of energy from FAFH was associated with an increase in BMI of 0·01, 0·01, 0·01, 0·02, 0·02 and 0·03 kg/m2 at the 5th, 25th, 50th, 75th, 90th and 95th quantile, and an increase in WC of 0·04, 0·06, 0·06, 0·04, 0·06, 0·05 and 0·07 cm at the 5th, 10th, 25th, 50th, 75th, 90th and 95th quantile. For females, percentage of energy from FAFH was associated with 0·01, 0·01, 0·01 and 0·02 kg/m2 increase in BMI at the 10th, 25th, 90th and 95th quantile, and with 0·05, 0·04, 0·03 and 0·03 cm increase in WC at the 5th, 10th, 25th and 75th quantile.

Conclusions

Our findings suggest that FAFH consumption is relatively more important for BMI and WC among males rather than females in China. Public health initiatives are needed to encourage Chinese adults to make healthy food choices when eating out.