3 biggest mistakes people make when trying to improve their gut health, according to a gastroenterologist

• Gastroenterologist Dr. Will Bulsiewicz shared the three biggest gut health mistakes people make.
• These include restricting their diets and relying on supplements.
• Instead, eat lots of fiber from a diverse range of plants, he said.

A gastroenterologist shared the three biggest mistakes people make when trying to take care of their gut health.

Gut health is a buzzy topic: rates of colorectal cancer are rising among under-50s, irritable bowel syndrome is thought to affect between 10 to 20% of people in the West, and experts fear pervasive diet culture is normalizing stomach issues.

At the same time, people can struggle to get gut problems treated because the causes of some are unknown. (There's no cure for IBS, for example). So some sufferers turn to restrictive eating and supplements to try to relieve their symptoms.

But such tactics can actually make gut issues worse, Dr. Will Bulsiewicz, a gastroenterologist and US medical director of nutrition company ZOE, told Business Insider.

Addressing the following habits may help, he told Business Insider, but if you're worried about your gut health, speak to your doctor.

Relying on supplements

In 1994, there were around 4,000 dietary supplement products available to buy in the US, according to official figures. Now, there are as many as 100,000 — from the classic vitamin C pills and fish oil capsules to fiber supplements such as psyllium husk and trendy pre and probiotics.

"Supplements are beneficial, but not in competition with food. So don't try to out-supplement a bad diet," Bulsiewicz said. "Have your healthy food, with lots of fiber and a diversity of plants, and then compliment that with supplements."

He added: "You can't go from a C-minus gut to an A-plus with supplements alone — diet has to come first."

BI previously reported that Bulsiewicz no longer prescribes probiotic supplements regularly, preferring instead to recommend fermented foods such as kefir and yogurt to his patients.

This chimes with the "food-first" approach that many dietitians advise their patients take — by getting nutrients from food and then supplementing for things their body is deficient in or that their diet doesn't provide enough of.

Following restrictive diets

Bulsiewicz said restrictive fad diets are a "major reason" people struggle with gut issues. Cutting out food groups means a smaller variety of foods enter the gut, and the microbes that populate our digestive system — known as the gut microbiome — "suffer the consequences," he said.

There are thousands of different types of microbes in the gut, all fuelled by different foods. Bulsiewicz thinks of them as little people with food preferences and "cliques" of other microbes that they function alongside.

"If we want all of our microbes to do their jobs, they all need to be fed. In order to feed all the microbes you need to create basically a varied buffet for them," he said. "So a gut-healthy diet is a diet of abundance and variety."

He previously shared his method for getting as many gut-healthy foods into his diet as possible with BI.

Misinterpreting bloating

Many people misinterpret bloating as their bodies rejecting certain foods. But that isn't necessarily true — you could have eaten more of that food than your gut could handle, or most likely, it's because you don't have a healthy gut microbiome, Bulsiewicz said.

If you don't eat a certain food often, the gut microbiome might not be used to it, which could cause bloating as the body struggles to digest it.

"The healthy foods that cause those symptoms are, in fact, the foods that you probably need the most" to increase gut microbiome diversity, Bulsiewicz said.

Instead of eliminating healthy foods that cause bloating, start by eating smaller amounts and slowly work up to larger portions to incorporate them into your diet.

"It's like going to the gym for your gut — except you're doing it with a fork," he said.

Bulsiewicz previously told BI you can "max out your diet" by increasing the fiber, fermented foods, and variety of plants you eat.