Why is everyone talking about gut bacteria?

"Go with your gut" is becoming a health mantra, as science learns just how important the bacteria in our large intestines are for our overall wellbeing.

So important, in fact, that recent research found gut bacteria has as much influence on health as an organ – just like your skin, kidneys or lungs.

Science is just starting to discover that your gut bacteria affect a whole lot more of you than simply whether you have an upset tummy. Intestinal microbiota has been demonstrated to influence brain development, eating disorders, asthma and even behaviour.

It's important to note that we have a lot of bacteria in our large intestines – almost 1.5kg of tiny microbes that feed on everything we consume.

To put that in perspective, there's about 10g of microbes in your nose, 20g in your mouth and 200g on your skin. So to gain the most benefit from your gut flora, you've got to look closely what you're consuming each and every day.

A clash of definitions

Since the science of gut bacteria is still emerging, there's a whole cacophony of jargon that essentially refers to the same processes and bodily locations.

Dr Rebecca Reynolds, lecturer and nutritionist at the University of New South Wales, says many definitions are interchangeable – and it depends on whether you're talking about where the bacteria live, or what it does.

"There are combinations of terms that mean the same thing. Gut, intestinal, large intestine, bowel and colonic are all relatively the same thing," Reynolds tells ninemsn Coach.

"Just like flora, microflora, bacteria, microorganisms, microbiome and microbiota all mean relatively the same thing too."

So what does the bacteria in your gut actually do?

As we're discovering, gut bacteria plays an important role in your keeping your immune system, energy levels and organs functioning healthily. It does this by taking on the tough job of breaking down foods that aren’t digested easily.

"Gut bacteria feed on food that reaches our colon, primarily less-digestible carbohydrates, like fibre, which then produces short-chain fatty acids and gas," says Reynolds.

It turns out that despite the name, these short-chain fatty acids are incredibly beneficial – helping to convert food into energy, moderating immune function in your gut and reducing inflammation all over the body.

What's the difference between "good" and "bad" bacteria?

In much reporting bacteria is described as being "bad" or "good", a lot like the Force from Star Wars. It's not inaccurate to describe the bacteria this way – it’s simply the best way we currently have available.

"We have bacteria living in our gut all the time that can have 'good' effects, for example bifidobacteria, and 'bad' effects on our health," says Reynolds.

"A poor diet over time, like one that is low in fibre, can increase the number and function of bad bacteria, which can produce harmful compounds that may be linked to colon cancer, inflammatory bowel disease, liver disease and more."

How to increase the "good" bacteria

To help your intestines fight a biblical war of good and evil, you need to eat more fibre, recommends Reynolds.

"Fibre, fibre, fibre! Prebiotics, which are taken to improve gut health, are basically fibre," says Reynolds.

"Aim to eat two serves of fruit and five servings of vegetables a day or more – for example, young men are meant to have six serves of veggies per day."

RELATED: Why probiotics and prebiotics are the best friends you'll make

Fibre is important for gut health because it helps you to pass bowel movements easier, warding off disorders that include constipation, irritable bowel syndrome, heart disease and some cancers.

Simply – it's bad physically and emotionally to be full of sh... er, a little backed up.

Soluble vs. insoluble fibre

We need to consume fibre every day, but not all fibre is the same – it comes in two forms, soluble and insoluble.

Soluble fibre is easily digested by your body, and attaches itself to cholesterol particles in your gut, passing them out through your bowels, and helping to prevent heart disease.

Insoluble fibre on the other hand is not digested by your body, and helps to keep your digestive tract moving by drawing moisture into your stool, bulking it up.

The Dietititans Association of Australia (DAA) recommends Australians get at least 25 to 30g of fibre a day, which includes a variety of both soluble and insoluble fibre.

Dr Reynold's list of fibre sources:

Soluble

·         Oats

·         Legumes

·         Barley

·         Fruits

·         Vegetables

Insoluble

·         Whole grains

·         Bread

·         Rice

·         Cereals

·         Nuts

·         Seeds

Fruit and vegetable peels