First broadcast September 2005
In this documentary, the body gets a chance to speak for itself. The body itself - played by Nina Wadia - tells us what's going on when we the flesh and blood is put through the extremes of modern life.
Part 2: The Fast
Have you ever wondered what happens inside your body when you fast?
Most religions have practised short-term modified fasting for centuries.
But now, new-age health spas advocate lengthy fasts and "colon cleansing" as an alternative therapy.
When you fast, the body enters the so called starvation mode mechanism, and its metabolic rate slows down.
Understanding fasting has led to better understanding of dieting. It is now well-known that crash diets do not work.
In this programme, the Body checks in to the Happy Colon Health Spa and is put through a rigorous eight-day fast.
With the help of one of the world's leading dieticians - and the doctor who treated the illusionist David Blaine when he ended his 44-days without food - the Body describes its critical battle to maintain vital blood glucose levels and the extraordinary emergency procedures it can call upon for warding off starvation.
The Body takes centre stage as it describes hour by hour the battle to stay fit and well without food.
The BBC Podcasts are for your personal non-commercial use only.
All title, ownership rights and intellectual property rights in and to the BBC Podcasts shall remain the property of the BBC or third parties.
You may not edit, alter, adapt or add to the BBC Podcast in any way.
The BBC Podcasts are made available by the BBC on an "as is" and "as available" basis and the BBC gives no warranty of any kind in relation to the BBC Podcast.
To the maximum extent permitted by law the BBC will not be liable for any loss or damage which you may suffer as a result of or connected to the download or use of the BBC Podcasts
See the full BBC Podcast: Standard Licence Terms here.