[Correspondence] Portion sizes and caloric inequity: a hidden driver of obesity disparities

Multiple factors contribute to rising obesity rates. However, excess caloric intake remains the primary driver. This conclusion is supported by multiple lines of evidence, including observational studies, and is intuitively plausible: consuming several hundred calories can take mere minutes, whereas expending the same amount often requires hours of sustained physical activity.1 Obesogenic environments have exacerbated this imbalance.2