Kidney Basics Overview

Your kidneys are bean-shaped organs found below the rib cage on either side of the spine. Each one is roughly the size of your fist and weighs 1/3 of a pound. They filter 30-40 gallons of blood per day. They also create urine which contains excess waste, electrolytes and water. Blood flow to the kidneys is important. They receive 20% ...

How Kidneys Work

The kidney contains many types of specialized cells. One functional unit of a kidney is called a nephron. Each kidney has around a million nephrons, and every nephron has 2 parts: Step 1     The glomerulus receives circulated blood and acts as a filter. Water, electrolytes and urea pass through but large proteins such as albumin* are blocked. Step 2   ...

What Does a Kidney Do?

The kidneys maintain the environment required for the perfect functioning of your body’s cells. They remove waste and adjust for the elimination of water and electrolytes (including sodium, potassium, chloride, calcium, magnesium and phosphate). The kidneys buffer body acid to balance our pH levels (normal ranges from 7.35 to 7.45). Acid accumulation lowers one’s blood pH, which could lead to ...

Glomerular Filtration Rate (GFR)

Glomerular Filtration Rate (GFR) is the rate that the kidney filters the blood per minute. It is the best measure of kidney function and is a rough indicator of how well your kidneys are working. Normal GFR is 90-120 mL/min (180 L/day), and is higher in men than women. The lower the GFR, the worse your kidney function. This puts ...

Blood Urea Nitrogen (BUN)

BUN stands for Blood Urea Nitrogen. Nitrogen is an essential element of amino acids, which are the building blocks of protein. When we eat protein-rich food, it is broken down by our digestive system into amino acid. This amino acid has 1 of 2 fates: It is either used to make protein for muscle formation, or the liver degrades it ...

Creatinine

Creatinine comes from the breakdown of creatine in your muscle.  It is produced by the body at a constant rate and eliminated through urine.  This makes it a good a marker to assess your kidney function. The higher the blood creatinine, the worse the kidney function. Sometimes, blood creatinine varies without a change in the GFR or kidney function. Low muscle mass caused ...