Can add calories. So it can impact your overall weight. Milk can put more work on some parts of the body. Such as organs, kidneys, and the liver. Milk is very efficient with rehydration. Most of the time when you drink it signals the kidneys to get rid of the extra water by producing more urine.When beverages contain nutrients and electrolytes like sodium and potassium, such as milk, the stomach empties more slowly with a less dramatic effect on the kidneys.