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Fascinating Facts About Your Gut

Ten facts about the body’s most underrated organ....

1. What is the gut?

The gut starts with the mouth and teeth and finishes at the end of the large intestine. It includes the oesophagus, the stomach, the small intestine, the colon or large intestine, the pancreas, the liver and the gall bladder.

2. The crowded gut

Your gut is home to tens of millions of microscopic organisms, or microbes. There are more than 100 billion bacteria to every gram of intestinal content and 10 times as many microbes as there are cells in your body.

3. Size matters

Your gut is a big deal. It’s a 9m-long organ with between 800 and 900 folds, and would cover an entire tennis court if laid out flat. It makes up roughly 70% of your immune system and contains 1.5kg to 2kg of bacteria – more than the weight of your brain.

4. Your gut feeling

Guts have been called a ‘second brain’ because if the nerve between brain and gut  (the vagus nerve)  were cut, the gut would function independently. The gut produces more neurotransmitters – which affect mood and behaviour – than the brain does.

5. Keep calm and digest

Stress produces an influx of adrenalin, which shuts down digestion and can cause bloating, so take deep breaths and relax while eating.

6. Unique microbiomes

Everyone’s gut is unique. Even identical twins, who share 99.5% of their genes, only share about 20% of their microbiomes.

7. Overdone it?

If you’ve eaten too much and want to digest it as quickly as possible, lie on your left side. Your stomach is asymmetrical and empties more easily on that side. The design also allows liquids to flow down one side while food goes down the other.

8. Self-cleaning

The gut also has its own cleaning system. An hour after eating, the clean-up starts with a powerful wave of peristalsis moving through the tubes. This distinctive pattern of movement is thought to move along any undigested food.

9. Smells the same

Despite what you might believe, men do not produce smellier wind than women. The smell is caused by the fermentation of unabsorbed carbohydrates and protein, and depends on what you’ve eaten, how much of it isn’t absorbed and the effect of stress on the process.

10. Strong stuff

Stomach acid is strong enough to burn your skin, but it does not harm the inside of your stomach because of the thick lining of mucus which protects it. The acid is churned with your food as part of the digestive process.


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