It is hard not to notice the discrepancies that exist between what we all see in our everyday lives and what we are being told about body size, dieting, and exercise. If the conventional wisdom from the medical communities and dieting industry were right on correct, there would not be an "obesity epidemic." When you went to renew you driver's license or go anywhere else people gather randomly, you would be seeing a lot more thin people. The observable truth is that, over the long term, people rarely significantly alter their genetic, age-relative size range through any mix of diet and exercise. This examination presents a more practical model of how the body works that explains to a much greater degree what each of us observes in our daily lives. The model is aligned with scientific data and suggests a lifestyle of sustainable physical activity with better nutrition - not to get thin, but to promote better health within a range of body types and sizes.