FARTING is entirely normal - with most people letting one rip about 20 times a day!
While sometimes the smell can be hideous, other days it's barely noticeable - a mere puff in the wind.
One of the reasons we produce so much more gas than we realise is that is odourless.
has found that bad smells only apply to about one per cent of the gas that people expel.
Our efforts to conceal the fact that we fart - stinky or not - isn't doing our health - any favours, according to Hollywood actress Demi Moore.
The 61-year-old starlet has recently launched a taboo-busting campaign to end the silence around tooting.
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"Farting ... we all do it! So let's talk about it," she wrote in a .
The actress joined forces with Wonderbelly antacids to champion their fresh-off-the-press picture book titled 'An Adult's Guide To Farts'.
The star told : "Digestive health is an important yet often taboo topic.
"As babies, we're celebrated for bodily functions like pooping and farting, but as adults, we often hide these normal processes.
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"Conversations I had with Lucas, a founder of Wonderbelly, inspired the 'An Adult's Guide to Farts' book, highlighting that accepting these functions is better for our physical well-being."
But why do our toots sometimes smell really bad?
Here we explore the reasons for stinky farts and how to stop them occurring.
Just as a warning, the NHS says: “Do not self-diagnose. See a GP if you're worried about your farting.”
1. Food
Probably the most common culprit for smelly farts is the food you’ve eaten that day, or the day before.
Your stomach struggles to break down certain foods as they move through the bowel, causing gas.
For example, beans contain sugars and fibre that our bodies have a hard time digesting.
But they are also beneficial in the diet - hence the saying “beans, beans, they’re good for your heart, the more you eat, the more you fart”.
But if these foods create more gas, what is it that makes it smell?
Alex Glover, senior nutritionist at , explained the chemical that leads to a pong is hydrogen sulphide.
This is produced when gut bacteria break down sulphur in foods.
Alex told The Sun: "More hydrogen sulphide is produced by the body when it breaks down protein rich foods.
"This is why we may notice our farts smell more after a meat-heavy meal, or a protein shake."
Rob Hobson, head of nutrition, agreed that meat - particularly fatty cuts such as beef and pork - "could get a bit smelly".
He said: “They can take a long time to digest in the gut which leaves them to ferment.
“Fatty meats in particular are rich in methionine which is an ammonia acid containing sulphur."
Rob explained that hydrogen sulphide gas gives farts "that delightful rotten egg odour".
But it's not just meat eaters that are affected.
Other sulphur foods that can make you wind a bit whiffy are:
- Broccoli
- Brussels sprouts
- Cauliflower
- Cabbage
- Garlic
- Onions
- Legumes (beans, peas, chickpeas)
- Nuts and dried fruit
- Beer and wine
Rob also said to watch your intake of artificial sweeteners in diet drinks, sweets and gum. These are sugar alcohols and are healthier than the real deal.
But Rob added: “As with other culprits of bad gas these are not fully absorbed in the body travelling to the colon where they contribute to foul-smelling gas.”
2. Food intolerance
A food intolerance - such as to dairy or gluten - can cause smelly gas.
You would likely also experience symptoms like indigestion, bloating, constipation and diarrhoea.
Rob said: “Food intolerances can leave you with bad-smelling wind if you eat the wrong foods.
“An example here is lactose intolerance where people lack the enzyme required to break it down.
“This means lactose travels to the gut indigested where it is fed upon by the bacteria leaving you with smelly gas.”
Millions of people are intolerant to lactose - a natural sugar found in dairy products such as cheese, milk and ice cream.
It doesn’t help that dairy foods are also higher in sulphur content.
Meanwhile, coeliac disease is an autoimmune disorder when the body reacts to the digestion of gluten, found in bread, pasta, cereal, and many more common foods.
The digestive system will react adversely to the protein, causing severe abdominal pain and excessive bloating.
If you believe you have an intolerance to something, it's probably worth getting checked by you GP.
3. Constipation
When you let off a stinker, one of the main things your poor victims around you will question is, “do you need to go to the toilet?”.
Often they aren’t wrong - the potential cause of your smelly farts could be constipation.
Constipation occurs when stool builds up in the colon or large intestine but isn’t able to exit.
The build-up of stool in the colon often leads to the creation of smelly gases - which may also cause bloating and discomfort.
This may occur even if you don’t feel you’ve eaten gassy foods.
Bread, pasta and pizza are not known for creating pongy gas.
However, if no fibre is eaten with them - and fibre is the key ingredient to regular stools - you’ll have difficulty keeping the bowels moving, and things might get smelly.
Speak to a pharmacist if diet and lifestyle changes are not helping.
They can suggest a suitable . These are medicines that help you poo more regularly.
Most laxatives work within 3 days. They should only be used for a short time.
4. Medication
Excessive or smelly wind can also be a side effect of some medicines, so if you have recently been given a new prescription, that could explain your symptoms.
But even some over-the-counter meds, like ibuprofen, are a risky game.
Medicines that can cause gas include:
- Non-steroidal anti-inflammatory drugs (NSAIDS), like ibuprofen
- Some laxatives
- Antifungal medicines
- Statins
Do not stop or change your medicine without speaking to a GP first.
When to worry...
The NHS states that you should see a GP if farting is affecting your life and treatments from the pharmacy and self-help haven't worked.
You should also book in to see a medic if you have a stomach ache or bloating that will not go away or keeps coming back.
If you keep getting constipation or diarrhoea or if you've lost weight without trying then you should also see your GP.
If you've had blood in your poo for three weeks or longer then it's important to get help.
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These symptoms might be down to issues like constipation or irritable bowel syndrome.
But if in doubt, go and get checked out.