Transportation of water through the human body

Water is key to life.

Humans can survive more than a month without food, but only a few days without water.

Water is found inside and outside cells and circulates in the blood.

Our bodies are about 60 percent water.

Our lungs are 90 percent water,

Our brain is 70 percent water.

Our blood is more than 80 percent water.

Simply put, we can't function without water.

Role in the bodyWater plays many important roles in the bodyincluding:

Transportation • Water transports glucose, oxygen, and fat to

working muscles.• Water transports waste products, such as

carbon dioxide and lactic acid away from working muscles.

Body temperature regulation • The body wants to keep a constant temperature

of approximately 37ºC. • Working muscles generate heat. The body can

generate 20 times more heat when working, than when at rest.

• To prevent overheating, the body regulates temperature by sweating.

• Sweat evaporates from the skin, which cools it down. This cools down the blood and the rest of the body.

Urine • Water transports and eliminates waste-products in

the urine.

Digestion • Water is an important component of saliva and

gastric juices, which help digest food.

Lubrication • Water is a good lubricator of joints, organs, and

tissues.

Role of water in the body

• Most people sweat out about 0.5 litres of water.

• Lose about a quarter of a litre when we exhale it.

• Eliminate (pee) about 1.4 litres of it.

Each day:

How do we replace it?

• We can get about 20 percent of the water we need through the food we eat.

• You can get your water by drinking water and other beverages.

You need more water:

• When you are exercising.

• If you are ill with diarrhoea, vomiting or fever.

• If you’re in a hot environment for a long time.

• When you don't get enough water, or lose too much water, you become dehydrated.

What is the difference between a raisin and a grape? Water!

Dehydration caused by diarrhoea is a major causeof death in undeveloped countries.

Nearly 2 million people, mostly children, die from iteach year [source: World Health Organisation].

Consuming water polluted with biologicalcontaminants and not having access to adequatesanitary facilities can lead to diseases like malariaand cholera.

Water can be also be contaminated with chemicals,pesticides and other naturally occurring substances.

Links to – ‘A Long Walk to Water’