Creatinine is transported through the bloodstream to the kidneys. The kidneys filter out most of the creatinine and dispose of it in the urine. Because the muscle mass in the body is relatively constant from day to day, the creatinine production normally remains essentially unchanged on a daily basis.
When you have an upset stomach, avoid acidic foods, he says. 1  Fatty Foods Fatty foods stimulate contractions in the digestive tract, which, surprisingly, can either slow down the emptying of the stomach and worsen constipation or speed up movement and worsen or lead to diarrhea.
Juices and soft drinks should be avoided. Eat as tolerated, but only light, bland foods, such as crackers or plain bread to begin with. If your nausea is chronic, you'll need to find a variety of vegetables and proteins that don't upset your stomach to maintain proper nutrition. Stay away from fried or greasy foods.