“But, more often than not, they don’t live up to the claims,” warns Gill, who is also a spokesperson for the British Dietetic Association. “Many brands contain lots of added ingredients to enhance the taste and texture.”

These include emulsifiers, flavourings and sugar, which may be labelled as golden or brown rice syrup or date or coconut sugar on the packaging. “Using other names for sugar disguises the fact they contain added sugars,” she notes.

Researchers are worried that these artificial ingredients can cause problems with our gut. Emulsifiers, in particular, have been linked to disruption in the gut, while animal studies have highlighted that they may play a role in the development of bowel cancer.

Swap for: Homemade oat bars

If a grab-and-go breakfast suits your morning, Gill says the healthiest option is to make your own breakfast bars ahead of time. They can be made by combining just three ingredients: oats, banana and peanut butter.

The big bowl of cereal

“Breakfast cereals can be confusing to navigate,” says Dr Gill. It’s how a quarter of people in the UK start the day but their ingredients list and the amount of sugar they contain vary drastically – meaning what you pour into your bowl can have implications for your health.

Sugar-coated cornflakes are, of course, high in sugar and low in fibre (often containing the equivalent of three sugar cubes and only 0.5g of fibre per 30g portion), which is a disaster for our gut, she says.

Research suggests that too much eliminates beneficial bacteria from our microbiome, while fibre is essential for the gut as it feeds the bacteria living in it.

However, some low-sugar cereal options also offer barely any fibre (such as plain puffed rice) while some sugary options, such as sugar-coated shredded wheat offer a decent fibre hit.

Swap for: Porridge

“I would always recommend choosing a plain, high-fibre option then adding your own toppings,” Gill says. Porridge, or if you’re in a rush plain wheat biscuits and shredded wheat, are all safe bets.

You can then add honey or fruit to sweeten these more bland options but, importantly, can control how much, she says. “You can add extra toppings such as seeds and nuts for extra fibre, protein and healthy unsaturated fats. One of my personal favourites is porridge with mashed up banana and peanut butter.”

The classic bacon sandwich

“A bacon sandwich is high in salt and low in fibre,” Gill notes.

If eaten too often, bacon can be toxic for our gut health. The World Health Organisation (WHO) has classified processed meat, which includes bacon, as carcinogenic – meaning there is strong evidence that it increases risk of cancer, most notably bowel cancer.

“The WHO found that eating 50g of processed meats a day increases the risk of developing colorectal cancer by 18% over a lifetime,” she notes.

Swap for: A wholegrain version with tomatoes

“Let’s be realistic – the advice is to limit, not totally avoid bacon, unless you want to,” Gill says. “Just be mindful of the amount you’re having and how often.”

If you enjoy a bacon sandwich, have it now and again instead of regularly, she says. There are also simple ways to improve the nutritional value of a classic bacon sandwich, as well as making it more gut-friendly, such as by using wholegrain or seedy bread instead of white, and adding some fresh tomatoes.

“You could even swap out the bacon for veggie sausages, chicken sausages, or smoked tofu,” she adds.

Shop-bought smoothies

“Shop-bought smoothies contain the liquid and solid parts of fruit – both the fruit juice and flesh blended-up,” Gill explains. While this sounds nutritious, the blending process reduces the amount of fibre the fruit has to offer and pushes up the sugar content.

While they still offer some fibre and compounds good for gut health, such as plant compounds called polyphenols, there are more gut-friendly ways to start the day.

Swap for: Homemade smoothie made with oats, nut butter and seeds

“Homemade smoothies are your best bet – simply because you can make it more nutritious by using all edible parts of the fruits and vegetables, including the juice, flesh, seeds and skins,” she says.

The skins are a concentrated source of fibre, polyphenols, vitamins and minerals. “For example, leaving the skins on can increase the fibre content by up to 50%,” Gill says.

“If you’re adding other ingredients such as cow’s milk, oats, nut butter or chia seeds, you’re adding extra fibre, protein, and healthy fats to your smoothie too.”

The wrong glass of juice

Fruit juices provide a concentrated source of sugar, mainly in the form fructose, which can trigger symptoms like bloating, flatulence and diarrhoea in people with a sensitive gut, Gill notes.

The drink is also full of free sugar, the type we’re told not to have too much of because it contributes to weight gain and tooth decay. Typical advice is to limit free sugars to 30g per day but a single 150ml glass (the recommended serving size) contains up to 18g.

However, this doesn’t mean that fruit juice can’t be part of a healthy diet. “In fact, studies have shown that drinking orange or apple juice is linked with lower levels of inflammation and improvements in cardiovascular health, such as cholesterol levels,” she says.

Swap for: 100% fruit juice or fruit tea

Instead of going for a “fruit juice drink” or “fruit-based drink”, which are more likely to have lots of sugar, always choose 100% fruit juice, Gill says.

“Juice drinks are not 100% fruit juice,” she explains. “They are bulked out with other ingredients such as sweeteners, colours and flavourings. To reduce the sugar load, you could mix fruit juice with 50% water, have fruit-infused water or fruit tea.”

A full English

“A full English breakfast has a reputation for being an unhealthy option, mainly because items are typically fried which increases the amount of fat and calories,” Gill notes.

Typically, an English breakfast wouldn’t be complete without two sausages and two rashers of bacon, which adds up to 130g of processed meat. The NHS recommends having no more than 490g of red or processed meat per week as the preservatives they contain can damage the cells that line the bowel, leading to bowel cancer.

“It’s not recommended to consume these types of meats on a regular basis,” Gill confirms. Eating too much processed meat has been linked with lower gut microbial diversity (which is thought to worsen overall health) as well as bowel cancer, she notes. They are also generally high in salt and fat.

Swap for: Chicken sausages, baked beans, wholegrain toast and grilled vegetables

“Another option is to try sausages made with chicken or turkey,” Gill says. “Typically, fewer ingredients on the nutrition label are better choices.”

Carefully selecting the components of a cooked breakfast can make it much more “gut healthy”, she adds. “Baked beans are a must – these are high in fibre, packing in around 8g per half can (a quarter of your daily recommended fibre intake).

“Add a couple of slices of wholegrain toast. Grill some mushrooms, tomatoes, and spinach – all of these plant-based foods are rich sources of fibre, plant chemicals, as well as vitamins and minerals, which all support gut health.

“Drizzle with extra virgin olive oil – known for its anti-inflammatory properties, it contains plant chemicals that are linked with supporting gut health and overall health.”

However, you can still enjoy a traditional full English as an occasional treat, Gill says. Even then, it can be made better for your gut and overall health by cutting visible fat off the bacon and grilling the meat, rather than frying it, she says.

A shop-bought flavoured yogurt

“Flavoured yogurts are typically higher in sugar and other additives such as emulsifiers, flavourings, thickeners and sweeteners,” Gill notes. This means that, not only are these yogurts ultra-processed foods, they can cause problems for our gut.

While yogurt contains naturally occurring sugar in the form of lactose, this only accounts for around 5g of sugar per 100g. “Anything above that will be added sugar,” Gill says. Popular yogurts contain up to 20g of sugar per 100g.

Swap for: Plain yogurt with nuts, seeds and fruit

Swapping to a plain yogurt and adding your own flavourings will do wonders for your gut, Gill says. Greek is higher in protein and lower in lactose (natural sugars) than regular yogurt, while “live” yogurts have more gut-friendly bacteria.

Two portions of yogurt per week can also help to protect against bowel cancer, possibly because the probiotics it contains encourages a wider array of beneficial bugs to live in our gut, which has a knock-on effect of less inflammation and fewer cancer-causing chemicals, scientists believe.

Gill suggests adding healthy toppings for flavour and extra gut health benefits, such as fruit, nuts, nut butter, seeds and dark chocolate chips.

A pastry

While flaky and delicious, pastries don’t contain any ingredients that will benefit your gut health and even contain a few that could harm it. “They are high in saturated fat and calories, and low in protein and fibre,” Gill says.

Research suggests that a diet with too much saturated fat reduces gut diversity and triggers inflammation.

Swap for: occasional pastry with fruit

Rather than banning them from your diet, Gill suggests enjoying pastries occasionally with a serving of plain yogurt and berries to give your gut some fuel.

Alternatively, you could make your own fruity croissant bake at home using filo pastry, which is lower in fat than puff or shortcrust, she suggests.

Add a side of berries, yogurt, or turn into a fruity croissant bake. Top some with fresh or tinned fruit and bake for 10 minutes.

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