How to reduce your bowel cancer risk through diet, according to experts

Bowel cancer diet, woman eating fruit and porridge in a bowel. (Supplied)
Slash your risk of bowel cancer with lifestyle changes. (Supplied)

With obesity and alcohol linked to driving up cases of bowel cancer among young people in the UK, experts have shared their top tips for helping to prevent the disease through diet.

Bowel cancer deaths in people aged 25-49 are expected to rise by 26% in men and 39% in women, partly due to unhealthy lifestyles, according to the study published in Annals of Oncology.

Here, experts explain why obesity, diet and alcohol can increase your likelihood of bowel cancer, and how you can help cut the risk through what you eat and drink.

Obesity, alcohol and bowel cancer in young people

"Obesity, poor diet and excessive alcohol consumption increase the risks of bowel cancer [found anywhere in the large bowel, which includes the colon and rectum] in individuals aged 25 to 49," says Dr Babak from Superdrug Online Doctor.

"Obesity is associated with chronic low-grade inflammation, which can contribute to the development of cancer through inflammation triggering changes in the cells of the colon and rectum. Alongside this, obesity is often linked to insulin resistance, leading to increased levels of insulin which may promote the growth of cancer cells.

"Alcohol, acting as a carcinogen, damages DNA and generates cancer-promoting acetaldehyde, fostering oxidative stress and inflammation."

"The surge in deaths among younger individuals may stem from delayed diagnosis, changing lifestyles, and knowledge gaps," he adds. "Modern society's sedentary habits, widespread availability of processed foods, and increased alcohol intake contribute to this trend. Mitigating these risks involves promoting healthier lifestyles, increasing awareness, and enhancing screening strategies for early detection and intervention."

Preventing bowel cancer through diet

1. Increase fibre intake

High Fiber Foods on white wooden background, Healthy balanced dieting concept. Top view, flat lay, copy space.
Are you getting enough fibre? (Getty Images)

"Consuming a diet rich in fibre from fruits, vegetables, and whole grains helps maintain bowel regularity and may protect against bowel cancer. Fibre adds bulk to stool, reducing the time that potentially harmful substances are in contact with the colon lining," Dr Babak explains.

Highlighting a 'British fibre gap', a new report conducted on behalf of General Mills, maker of FibreOne, found less than half (45%) of survey respondents thought they were falling short on fibre, while almost four in 10 (38%) thought they were eating the right amount. But this doesn't tally with national intake data which shows that fewer than one in 10 (9%) reaches the recommended daily target of 30 grams.

Seven in 10 also didn't know fibre can decrease the risk of bowel cancer (and it can also help with other areas of your health).

GP Dr Gill Jenkins, advisor to the General Mills campaign, says: "Fibre helps to manage our blood sugar and blood cholesterol levels. It feeds the good bacteria in our gut, it encourages pathogens and other toxins to move through the digestive system and out of the body, and it prevents overeating by helping us feel fuller after meals.

"Not getting enough fibre throughout adulthood has several major health consequences. Particular areas of concern – when it comes to our huge fibre fail – include having an increased risk of getting type 2 diabetes, cardiovascular disease, or bowel cancer."

Dietitian Dr Carrie Ruxton, another advisor to the campaign adds: "It’s staggering that around one in 10 deaths from bowel cancer or heart disease globally are simply due to a lack of fibre – something that could easily be fixed. Increasing fibre by just 10g a day – the equivalent of three servings of fruit – has been shown to reduce the risk of heart disease by 15% and the risk of bowel cancer by 13%."

2. Reduce red meat intake

Man Frying Bacon in Frying Pan on Stove, Unhealthy Diet, Breakfast Food, Paleo Diet, Greasy Bacon, Greasy Food. Conceptual image for overeating and dieting.
Red meats like bacon have been linked to a higher risk of bowel cancer. (Getty Images)

"Processed and red meats, such as bacon, sausage, and beef, have been associated with an increased risk of bowel cancer. Limiting the intake of these meats can help reduce exposure to substances that may promote inflammation and DNA damage," explains Dr Babak.

The Department of Health advises people who eat more than 90g (cooked weight) of red and processed meat a day should cut down to 70g, to help reduce their bowel cancer risk.

3. Limit sugary and processed foods

Macro closeup of light yellow iced cupcakes in box
While not all processed foods are bad, some may contain high levels of salt, sugar and fat. (Getty Images)

"Diets high in sugar and processed foods have been associated with an increased risk of various cancers, including bowel cancer. Opting for whole, nutrient-dense foods can contribute to a healthier digestive system," adds Dr Babak.

The government recommends that free sugars (added to food or drinks, and sugars found naturally in honey, syrups, and unsweetened fruit and vegetable juices, smoothies and purées) should not make up more than 5% of the energy (calories) you get from food and drink each day.

Processed foods with ingredients like salt, sugar and fat added (such as salt in bread or sugar in cakes) are what to be mindful of.

4. Moderate alcohol consumption

Shot of two happy women sitting on the floor talking and drinking wine. Smiling friends toasting with white wine at home. Two female friends relaxing at home with glass of wine. Focus is on the wine glasses.
Too much alcohol has been linked to bowel cancer. (Getty Images)

"Limiting alcohol intake or abstaining altogether can reduce the risk of bowel cancer. Alcohol is a known carcinogen that can directly damage DNA and contribute to inflammation in the digestive tract," says Dr Babak.

It's recommended to drink no more than 14 units of alcohol a week, spread across three days or more according to the NHS. That's around six medium (175ml) glasses of wine, or six pints of 4% beer.

5. Stay hydrated with water

Man doing outdoor sports to stay healthy
As always, hydration is key. (Getty Images)

"Drinking an adequate amount of water is essential for overall health, including digestive health. Staying hydrated helps maintain bowel regularity and ensures the smooth passage of waste through the colon," explains Dr Babak.

The Eatwell Guide recommends aiming to drink six to eight cups or glasses of fluid a day.

Regular exercise can also help to lower the risk of developing bowel cancer, along with maintaining a healthy weight for you, and stopping smoking (if you do). It's recommended adults exercise for at least 150 minutes (two hours and 30 minutes) of moderate-intensity aerobic activity, such as cycling or fast walking, every week.

While screening can't prevent you from getting bowel cancer, it's crucial in detecting the condition at an earlier stage when it is easier to treat. Researchers from the Annals of Oncology study have called on governments to consider the extension of screening for bowel cancer to younger ages, starting at 45.

NHS bowel cancer screenings that check if you have bowel cancer are available to everyone aged 60 to 74 years. The programme is currently gradually expanding to make it available to everyone aged 50 to 59. Visit the NHS website for more information on bowel cancer screening.

See a GP if you have any symptoms of bowel cancer for three weeks or more, and ask for an urgent appointment if your poo is black or dark red or you have bloody diarrhoea.

Watch: George Alagiah: BBC colleague Jeremy Bowen urges people to check their poo for bowel cancer symptoms after death of newsreader