CONCLUSION
One clear message from this discussion of body composition is that we now have good ways to measure body fat and most other body constituents. There is also agreement that the BMI is a useful criterion for assessing overweight as a surrogate for obesity in most, but not all, cases. It is also evident that the prevalence of obesity has increased markedly in the last quarter of the twentieth century in all parts of the world. Evidence from the beginning of the twenty-first century suggests that this may have begun to level off. Finally, there are significant differences in fat distribution and in the prevalence of obesity among ethnic groups, income levels, and parts of the world.