Given otherwise comparable diets, the protein in soy causes abdominal fat to shrink 10-15 square centimeters, whereas the protein in milk may cause abdominal fat to increase 20-40 square centimeters (see also here). Soy appears to prevent human fat cells from taking up fat. Turmeric is also thought to have this effect on fat cells. It has been estimated that, on average, an inch is added onto the waist for every burger consumed per day. Conversely, bean consumption has been associated with lower body weights and smaller waist circumferences in adults.
A chicken virus has been discovered that actually causes obesity in chickens. It may even be a contributing factor in human obesity. Chicken meat today contains over 200 calories and 23 grams of fat per serving compared to chicken meat a hundred years ago, which only had 16 calories per serving and 2 grams of fat. This could help explain why chicken has been so tied to human abdominal girth.
Dioxins are toxic waste pollutants that accumulate in the fatty tissues of food animals consumed by humans (see also here). PCBs (found in fish oil) have been found to induce inflammation that promotes obesity. And other chemical obesogens may also be contributing factors in the obesity epidemic, possibly through the disruption of metabolism.
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