In the landmark starvation study conducted by Dr. Ancel Keys, by how much did the men's metabolic rate decrease?

The decrease in metabolic rate observed in Dr. Ancel Keys' landmark starvation study was significant, demonstrating the body's adaptive response to severe caloric restriction. During the study, which involved men undergoing a semi-starvation diet for a period of six months, findings showed that their metabolic rates decreased by approximately 30%. This dramatic reduction in metabolic rate is a key element of understanding the body's compensatory mechanisms when faced with food scarcity. When caloric intake is drastically reduced, the body slows down various physiological processes to conserve energy, which highlights the complexity of metabolic responses to hunger and deprivation.

Understanding this decrease is crucial. It illustrates not only the impact of starvation on human physiology but also underscores the importance of adequate nutrition in maintaining metabolic health. The study has been foundational in nutrition science, influencing how we view eating disorders, weight management, and the importance of energy balance.

While the other percentages may seem plausible, they do not accurately represent the findings from the study, which highlighted the 30% decrease as a critical observation in the context of starvation and its effects on the human body.