Nutrition and cancer: What to eat to reduce your risk

When it comes to cancer prevention, you're probably across the basics. Don't smoke. Reduce your exposure to the sun. Check in with your doctor if you notice worrying symptoms.

But did you know your nutrition is also linked to cancer?

While there's no one specific food or drink that's going to stop you from getting cancer, there are things you can prioritise and limit in your diet to reduce your risk.

Let's look at a few of them.

The World Health Organization classes red and processed meats as carcinogenic, which can increase your risk of cancer.¹

Red meat, which includes beef, pork and lamb, is considered a Group 2A carcinogen, and may increase your risk of bowel cancer (with some evidence also pointing to pancreatic and prostate cancer).

And, as a Group 1 carcinogen, processed meats (think hot dogs and deli meats) present an even greater risk for bowel cancer.

If you're a meat eater, it's recommended that you eat a maximum of 455g of lean, cooked red meat each week and avoid processed meats altogether in order to reduce your risk of cancer.²

High salt intake is linked to an increased risk of stomach cancer, and it's recommended that you consume no more than one teaspoon (or around 5g) of sodium each day.³

As well as limiting salt at the table, you should also be checking labels and limiting or avoiding foods that are high in added salt, like packaged or takeaway foods, cured meats and pickled or preserved foods. Look for foods labelled 'no added salt' or 'low salt' at the supermarket.

While it's not a carcinogen, a diet that is high in added sugar can contribute to overweight and obesity, which itself may increase your risk bowel, kidney, pancreatic and breast cancer.³

In fact, it's thought that 3.6% of all new cancers around the world are attributable to excess body weight.⁴

As well as limiting sugar in your cooking, make sure you watch out for foods that contain added sugar (like lollies, biscuits and soft drinks) and keep your daily added sugar intake to no more than 6 teaspoons worth.⁵

When broken down in your body, alcohol (which is also a known carcinogen) can damage your cells. And alcohol consumption is known to increase your risk of certain cancers, including bowel, breast, throat, oesophagus and liver cancer.⁶

Australian guidelines recommend that healthy adults consume no more than 10 standard alcoholic drinks per week (including a limit of 4 drinks in any one day).⁷

Limiting your intake of the above is your best nutritional defence against cancer. But there are some foods that you can prioritise in your diet, too.

Essentially, the best 'cancer-fighting' foods are those aimed at preventing bowel cancer, Australia's 4th most common cancer.⁸

Here, fibre is key.

This comes down to a few things. Foods that are high in fibre bind to carcinogens in the stomach (which you then excrete when you go to the toilet). Dietary fibre also converts into short chain fatty acids, which are known to protect against cancer.

According to the Australian dietary guidelines, it's recommended that you get in at least 25 to 30g of fibre every day, which can be consumed across each meal.⁹

This may include a balanced mix of things like:

These include lentils and beans, which can be thrown into salads and swapped in for meat (they make a fantastic mince substitute for spaghetti bolognaise!).

A balanced diet should include fibre-rich foods like rolled oats, whole grain bread, whole grain pasta and quinoa.

Fruit and vegetables are packed full of fibre and are a core part of any well-balanced diet. They shouldn't be overlooked.

As well as fighting against bowel cancer, fruit and veg contain vitamins, minerals and antioxidants that may further decrease your risk of other cancers, including those affecting your oesophagus, lung, liver, stomach, mouth and throat.¹⁰

This might seem like a lot, but it's very achievable. One helpful trick is to spread out your fruit and veg intake across the day, so you're getting a serving with different meals and snacks.

For dinner, half your plate should contain non-starchy vegetables like leafy greens, carrots, broccoli or cauliflower, one quarter should contain a protein like poultry, fish, meat or lentils, and the remaining quarter should contain whole grain carbohydrate, like potato, rice or pasta.

When it comes to fruit and veg, you should also aim to keep the skin on, as it contains added fibre!