Adult obesity: Panel study from native Amazonians

This paper examines three morphological indicators measuring obesity among a native Amazonian population of foragers-farmers in Bolivia (Tsimane') and estimates the associations between them and standard covariates of obesity (e.g., socioeconomic status [SES]). We collected annual data from 350 non-pregnant women and 385 men ≥20 years of age from all 311 households in 13 villages during five consecutive years (2002-2006). We used three indicators to measure obesity: body-mass index (BMI), waist circumference (WC), and body fat using bioelectrical impedance analysis (BF-BIA). We ran separate individual random-effect panel multiple regressions for women and men with wealth, acculturation, health, and household food availability as key covariates, and controlled for village and year fixed effects and village × year interaction effects. Although BMI increases by a statistically significant annual growth rate of 0.64% among women and 0.37% among men over the five years, the increase does not yield significant biological meanings. Neither do we find consistent and biologically meaningful covariates associated with adult obesity.

► We described weight changes among a Native Amazonian population in Bolivia (Tsimane'). We found no evidence that Tsimane' are gaining weight and becoming overweight and obese. ► We used five year panel data to examine the contributors, such as food availability, health, socioeconomic status, to the weight gain. We did not find consistent and biologically meaningful results. ► Results suggest caution when interpreting results of weight gain from observational studies in societies during the early stages of economic development.