What effect does insulin have on blood glucose levels?

Insulin plays a crucial role in regulating blood glucose levels by facilitating the uptake of glucose into cells, particularly muscle and adipose tissue. When carbohydrates are consumed, glucose levels rise in the bloodstream. In response, the pancreas secretes insulin, which acts to lower blood glucose levels by promoting the absorption of glucose by cells for energy or storage as glycogen in the liver and muscles.

By enhancing glucose uptake and inhibiting gluconeogenesis (the production of glucose from non-carbohydrate sources) in the liver, insulin effectively decreases blood glucose levels. This balance maintained by insulin is vital for metabolic homeostasis and overall health. Thus, the correct understanding of insulin's role confirms that it decreases blood glucose levels.