How to know if your ‘healthy gut’ habits are doing more harm than good

From bloggers to your bestie, these days it seems like everyone is obsessed with boosting gut health. But how can you tell the gimmicks from good practice?

Probiotics, fibre supplements, fermented foods – the quest for gut health is the new Holy Grail of the health industry.

It’s understandable, given CSIRO research shows 50 per cent of Australian adults suffer from bloating, gas and constipation, with one in seven experiencing distressing symptoms.

But while our desire for digestive wellness has spawned a multi-billion-dollar industry, experts warn some health trends may actually be doing us more harm than good.

Is our gut health really that bad?

According to research, gastrointestinal issues spiked during the pandemic.

This doesn’t surprise gastroenterologist at Royal North Shore Hospital, Dr May Wong, who says stress is one of the major causes of digestive issues.

Dr Wong says other factors include the increased use of antibiotics and medications that play havoc with healthy gut bacteria.

“I also believe the increase is closely linked with four major risk factors: tobacco use, alcohol use, unhealthy diets, and physical inactivity,” Dr Wong says.

What are we doing wrong?

Mater Hospital Director of Gastroenterology Associate Professor Jakob Begun says a healthy digestive system needs a diverse microbiome.

“The gut microbiome encompasses all the microorganisms, including bacteria, viruses and fungi that live within the gut,” Assoc Prof Begun, who is also the lead researcher into inflammatory bowel disease at The University of Queensland, says.

“These trillions of organisms living inside us, which on average have a biomass of 6kg, have evolved with humans over thousands of years.”

He warns that restrictive diets like keto, which limit the fruit, vegetables and wheat that support the gut microbiome, can lead to digestive problems.

Studies show that a wider variety of nutrients in the diet promotes microbial diversity and better gut health,” he says.

“Generally, a diet that is low in ultra-processed foods and refined sugars, while containing a diversity of fruits and vegetables while limiting excess consumption of animal fats is associated with good gut health.”

Why gut health fads might be sending the wrong message

Dr Eddie Kim, gastroenterology registrar at North Shore Hospital, says social media fads are a big part of the problem.

“Currently there are videos on TikTok tagged with #guttok that promote the improvement of gut health with diets which are not evidence-based,” Dr Kim says.

“For example, having a significant amount of coconut oil, aloe vera juice or olive oil – this, in fact, may cause gut irritation and lead to diarrhoea when used in excess.”

What does our gut actually need to thrive?


This is integral to good gut health – and more than 80 per cent of Australian adults don’t get the recommended 25-30g a day according to CSIRO research.

“Dietary fibre has many benefits for gut health, and many people find it challenging to get the amount of fibre they need, so natural fibre supplements can be helpful,” Associate Professor Begun says.

However, overdoing it can be just as problematic, and eating more than 70g a day can cause bloating, gas, nutrient deficiencies and increase your risk of a blocked intestine.

Fermented food

The good news for kombucha, kimchi and kefir converts is that early research indicates fermented foods can enhance the diversity of gut microbes and decrease inflammation.

A study by Stanford School of Medicine found a diet rich in foods such as yogurt, fermented cottage cheese and vegetables led to an increase in overall microbial diversity.

More prebiotics, less probiotics

Associate Professor Begun says despite us forking out millions of dollars on probiotics, there is no scientific evidence to back claims they improve gut health.

“One issue is the numbers – even a potent probiotic with 10’s of billions of live bacteria still only represents 0.01 per cent of the biomass in the gut – a literal drop in the bucket,” he says.

“And with little regulation of the probiotic industry, there are no controls on the quantity or type of live bacteria in probiotic preparations.”

He says studies have also shown using probiotics to restore gut health after a course of antibiotics can actually delay the return of a normal microbiome.

Instead, Associate Professor Begun says we should focus on prebiotics – the fibre, which generally comes from carbs, which our bodies can’t digest.

The best sources of prebiotics include apples, bananas, berries, barley, green vegetables, legumes, oats and wheat.

Written by Dimity Barber.