The Human Body: The Owner's Manual

Human bodies are very complicated. They should come with Owner's Manuals. But don't.

I am constantly amazed at the number of people who know very little about their own bodies. Many would like to know more but don't know who to ask or where to look.

So, here is the Owner's Manual you've always wanted but never had before.

Your Heart
The average heart beats 70 times a minute. In 70 years it will beat over 2,500 MILLION times. Each time it beats, your heart pumps oxygen and food rich blood around your body. Your body contains 8 to 10 pints of blood and in a day your heart pumps these 8 to 10 pints around your body no less than 2000 times. Your heart is roughly the same size and shape as your fist. A man's heart weighs slightly more than a woman's. Your heart will last longer if you avoid fats and excess stress.

Your liver
It weighs 2.5% of your weight and is on your right hand side looking down - just underneath your ribs. Your liver helps produce red blood cells, manufactures antibodies which fight infection, stores iron, vitamins and carbohydrates, produces bile which helps digest fats and breaks down drugs and poisons into waste chemicals. All this chemical activity produces so much heat that your liver plays an important part in keeping your body warm. Your liver will like you better if you eat less fat and drink less alcohol.

Your kidneys
You have two kidneys - one on each side of your spine, embedded in fat. Each kidney weighs just over one quarter of a pound. Both kidneys contain a complex filtration system. All the blood in your body passes through your kidneys every few minutes to have the waste substances taken out of it. If your kidneys don't work properly wastes will accumulate and eventually produce blood poisoning. Give your kidneys a treat by drinking plenty of fresh, pure water every day.

Your lungs
When you were born your lungs were small, solid and yellow. When you took your first breath your lungs expanded and turned pink. If you live in the country and breathe fresh air your lungs stay pink. If you smoke or live in the city your lungs gradually get darker. Your lungs ensure that the air you breathe in gets into your blood to provide the tissues of your body with oxygen. Your lungs hate smoke and love fresh air.

Your brain
If you are a woman your brain weighs about 1.25 kg. If you are a man your brain weighs about 1.4 kg. Packed with nerve cells your brain reaches its maximum size and potential at the age of twenty and then slowly deteriorates as cells die off thereafter. Specific parts of your brain have specific functions. For example, the back portion of your brain controls the sense of sight while the front part governs thought and personality. To keep your brain healthy, exercise it regularly - feeding it a variety of different tasks - and rest it occasionally.

Your bones
Your femur or thigh bone is the largest bone in your body. Some of the smallest are the bones in your wrist. There are over 200 separate bones altogether. To keep your bones strong and healthy make sure that your diet contains calcium.

Your intestines
They start with the oesophagus or gullet, include the stomach and duodenum, go on through the small and then the large intestines and end in the rectum. Altogether your intestines are around thirty feet long - most of it coiled inside your abdomen. The intestines have the job of digesting and breaking down the food you eat, absorbing the useful nutrients and getting rid of the waste. You can help your intestines by finding out - and then avoiding - the foods which upset them.

Your skin
Skin keeps the rest of your body neatly wrapped, protecting muscles and bones from injury and the weather. The skin on your palms and the soles of your feet is one twentieth of an inch thick but the skin on your face is ten times thinner. Peeled and stretched out you have got enough skin to make a couple of pillow slips. To keep your skin in good condition moisturise it regularly with a plain cream.

Your pancreas
Tucked in between your stomach and your duodenum your pancreas produces the enzymes and juices which help digest the food you eat. To help keep your pancreas in top condition avoid cigarettes, excess sugar and too much alcohol.

Your muscles
Half your body weight is made up of muscles - there are over 600 of them. Each muscle is a separate organ controlled by its own nervous system and supplied by its own blood vessels. To keep your muscles in trim, exercise them regularly - but rest them if they are sore or painful.

Copyright Vernon Coleman 2003