What hormone is primarily responsible for regulating blood sugar levels?

Insulin is the primary hormone responsible for regulating blood sugar levels. It is produced by the pancreas and plays a crucial role in maintaining glucose homeostasis in the body. When blood sugar levels rise after consuming food, insulin is secreted into the bloodstream. This hormone facilitates the uptake of glucose by cells, allowing them to use it for energy or store it as glycogen in the liver and muscles for future use. By promoting the storage of glucose, insulin helps to lower blood sugar levels back to a normal range.

Understanding insulin's function is essential, as it is directly linked to metabolic health. Conditions like diabetes occur when there is either insufficient insulin production or the body's cells become resistant to its effects, leading to chronic high blood sugar levels. In contrast to insulin, glucagon works to increase blood sugar levels by prompting the liver to convert stored glycogen back into glucose. Cortisol, a stress hormone, can influence blood sugar levels, but it primarily functions to manage the body's response to stress rather than directly regulating daily blood glucose levels. Adrenaline can also affect blood sugar levels, particularly during the fight-or-flight response, but it is not the main regulator like insulin is.