Write me a critical essay, using all the new modern scientific thought on hormones, about the calorie myth, how losing fat is more about sugar, insulin, and insulin spiking, not calorie consumption or calorie quote burning end quote period. Also a critique on the whole notion of quote burning end quote calories period.

Recent research into metabolism has revealed new insights into the role of hormones, which extend beyond the traditional calorie-based theories. Here are a few key findings on how hormonal differences and changes affect metabolism:

1. Estrogen and Metabolic Regulation: Estrogen plays a significant role in metabolic homeostasis, particularly in women. It not only impacts reproductive functions but also regulates adipose tissue, liver function, and muscle metabolism. For instance, estrogen’s interaction with insulin signaling pathways influences mitochondrial function and autophagy, which are critical in managing energy balance and fat distribution. This helps explain why women may have different metabolic responses compared to men, especially regarding fat storage and energy use  .

2. Sexual Dimorphism in Metabolism: Hormonal differences between men and women create distinct metabolic patterns. Women are more likely to store fat for long-term use, which may be tied to evolutionary advantages for reproduction. Men, on the other hand, tend to burn fat more readily during physical activity. These differences are shaped by sex hormones, particularly estrogen and testosterone, which affect how the body utilizes carbohydrates and fats .

3. Gut Microbiota and Hormones: Hormones such as estrogen and testosterone also influence gut microbiota, which plays a crucial role in metabolic health. Research suggests that changes in hormonal levels, like those during puberty or menopause, affect the diversity of gut bacteria, which in turn influences energy metabolism and can impact the risk of developing conditions like obesity or diabetes .

4. Newly Discovered Hormones: The discovery of a new hormone complex called fabkin has added to our understanding of metabolic regulation. Fabkin, a protein complex secreted from fat cells, influences energy signals in the body and has been linked to the development of diabetes. This discovery could open up new pathways for understanding how hormonal changes affect metabolism, particularly in the context of insulin resistance and energy homeostasis .

These emerging theories underscore the importance of hormonal regulation in metabolism, offering a more complex picture beyond simple calorie intake and expenditure. They suggest that hormones and their interactions with organs, like the liver and adipose tissues, significantly shape metabolic outcomes and health risks.