Imagine two friends, both committed to improving their health, who embark on the same popular diet. One sheds pounds effortlessly, reporting boundless energy and mental clarity. The other struggles, feeling sluggish and seeing little change on the scale. They eat the same meals, follow the same rules, yet their results are worlds apart. This scenario, familiar to many, exposes a fundamental flaw in our conventional approach to nutrition. It begs the question: Why do our bodies respond so differently to the same foods?