Regulatory hormones play a crucial role in determining fuel utilizsation within the body. Insulin stands as the primary hormone, influencing the levels of other hormones and the overall metabolism.

 

When blood glucose levels rise, insulin levels increase, signaling for excess glucose to be stored as glycogen in the muscles or liver. Any surplus can be converted and stored in fat cells as alpha-glycerophosphate. Insulin's main function is to maintain blood glucose levels within a narrow range, typically between 80-120 mg/dl.

 

The most significant spikes in blood glucose and insulin occur after consuming dietary carbohydrates. Proteins lead to smaller increases, as some amino acids can be converted into glucose.

 

Large quantities of fatty acids and ketones can also trigger insulin release, although to a lesser extent compared to carbohydrates and proteins.

 

Other hormones involved in ketosis include:

Growth Hormone: Released in response to exercise, decreased blood glucose, carbohydrate restriction, and fasting.Thyroid Hormones (T4 & primarily T3): T3 reduces protein breakdown, with T4 acting as a less active storage form of T3 metabolically.

 

Cortisol: Permits other hormones to function effectively and is released from the adrenal cortex, playing a role in various reactions related to fuel utilization. It aids in protein breakdown to glucose and fat breakdown.Epinephrine and non-Epinephrine, known as the "fight or flight" hormones, are involved in fat mobilization.

 

Epinephrine is released in response to stimuli like exercise, cold, or fasting from the adrenal medulla, while non-Epinephrine is released from nerve terminals. Both hormones play a role in mobilizing fats for energy in intense situations.