The kidneys are paired, bean-shaped organs that carry out many functions that are essential for the healthy functioning of the human body. They are approximately the size of a fist. They are situated below the rib cage in the middle of the back. Their functions include maintaining homeostasis, cleaning and filtering blood by removing waste materials, and maintaining the balance of fluids in the body.
Functions of the Kidneys
While we get the energy from the food that we consume, wastes are also generated in the process. After the body extracts the needed nutrients from the food, the metabolic wastes in the blood are removed by the kidneys. Wastes are also formed due to muscle activity, and exposure to toxins and drugs.
In a span of 24 hours, the kidneys approximately process 200 litres of blood in order to separate around 2 litres of waste materials and excess water to produce urine. The urine then passes through tubes known as urethra and is stored in the bladder until a person urinates.
- The waste removal from the blood is actually carried out in ‘nephrons’, which are small units inside the kidneys. A kidney has approximately a million nephrons.
- ‘Glomerulus’, a small blood vessel present in a nephron, interlaces with a ‘tubule’ which is a tube that collects urine. It acts like a sieve that keeps all necessary constituents in the bloodstream, allowing waste products and fluids to pass through and enter the urinary system. Some of the waste products and chemicals that are received by the ‘tubules’ may still be used by the body.
- The kidneys identify and sort out useful elements like sodium and potassium, and send them back to the blood to be utilized by the body. They regulate and maintain the level of necessary chemicals for the body to remain healthy.
- Moreover, they release ‘erythropoietin’, which is a hormone that acts as a bone marrow stimulant to produce red blood cells, and ‘renin’ that is responsible for regulation of blood pressure.
- ‘Calcitriol’ is also released by kidneys, which helps regulate calcium from bones and also helps maintain proper levels of chemicals in the body.
If the kidneys fail to perform the aforementioned functions, wastes would accumulate in the blood and cause severe damage to the body. If the kidneys are unable to remove waste, the blood volume would increase, which could give rise to high blood pressure. High blood pressure is a risk factor for cardiovascular disease
. A defect in the kidney system can lead to kidney or heart diseases
Besides high blood pressure, diabetes can also have an adverse effect on the kidney function. Therefore, people affected by these conditions must take all possible precautionary measures to lower the risk of kidney disease. Smoking, excessive consumption of alcohol, substance abuse, diabetes
, high blood pressure
, prolonged use of certain drugs, obesity, etc. are risk factors for kidney disease
. Thus, people should make healthy lifestyle choices, so that the kidneys are not overburdened.