(SACRAMENTO)An estimated 35.5 million Americans have kidney disease and more than 554,000 of them are on dialysis, according to the National Kidney Foundation.

Dialysis is a treatment to replace the filtering function of the kidneys. It removes waste and extra fluid from a person’s blood, and then returns the filtered blood into their body.

Most patients go to a dialysis center three times a week, where each treatment takes three to four hours to complete. Skipping dialysis can be harmful — causing fluid overload, high potassium and elevated phosphorus levels — and can lead to severe health problems.