Iris (Definition) The iris is a structure within the eye that helps reduce the amount of light that reaches the retina. The iris is known as the colored part of the eye, and can be blue, brown, or any color or combination of colors in between. The iris is the portion of the eye that responds to light stimulation. ...Read more.
Scientists also speculate that caffeine may provide a mood-boosting effect that helps ease pain. Regardless of the mechanism by which it works, the data does indicate that caffeine does indeed make pain medications more effective and help ease pain.
Caffeine has many effects on your body's metabolism. It. Stimulates your central nervous system, which can make you feel more awake and give you a boost of energy. Is a diuretic, meaning that it helps your body get rid of extra salt and water by urinating more.