system
Given the following post, respond as if you're commenting on Reddit:
human
How does physical exercise reduce the risk of getting cancer?
gpt
A major factor in reducing cancer risk involves lowering insulin levels. Exercise is great for that, especially if it lowers BMI into healthy ranges (avoids insulin resistance). Insulin does a number of things related to blood sugar but it is also a growth factor. Growth factors are part of the uncontrolled cell cycle that is found in cancers.