Reducing your cancer risk: 10 evidence-backed steps

Cancer Prevention Action Week is a yearly campaign led by the World Cancer Research Fund (WCRF) to raise awareness of what increases cancer risk, and what practical actions we can take.

Research from population and lab studies suggests that 4 in 10 cancer cases are preventable. The WCRF have turned the evidence around reducing cancer risk into 10 recommendations, designed to be a blueprint for individuals and society to reduce the incidence of cancer. So, let's look at what they are, and what that means for daily life.

1. Reach and maintain a healthy weight

This recommendation is about keeping your weight in the healthy range and trying to avoid weight gain in adult life.

What most of us don't realise is that body fat is an active tissue that behaves like an organ. It can send out signals that increase inflammation and cause levels of growth hormones to rise, which increases the risk of cancer developing.

The risk increases the more body fat you have, and the longer you carry excess weight. Checking your BMI is one way to measure whether you are a healthy weight, but BMI can't tell the difference between muscle and body fat, which can make it unsuitable for some people. So, an alternative is to calculate your waist to height ratio. You can try that here.

2. Be physically active

Being active on an ongoing basis reduces the risk of various cancers through its effects on hormones and immune function. Regular exercise can also help you reach and maintain a healthy bodyweight. But what does 'being active' mean?

• Aim for at least 150 minutes of moderate intensity activity a week (about half an hour a day) - this is anything that raises your heart rate and makes you breathe faster and feel warmer. Walking, cycling, carrying shopping, gardening - all count.
• Limit the time you spend sitting or lying down by taking walking or stretching breaks at work, taking the stairs, and including active hobbies or social activities in your free time.

3. Make wholegrains, vegetables, fruit and beans a big part of your diet

Here's how to build wholegrains (like oats, wholemeal bread and brown rice), fruits, vegetables and beans into your daily diet:

• Eat at least 5 servings of fruit and vegetables a day. One portion is equal to:
  • A large fruit like a banana or orange
  • Two small fruits like kiwis or satsumas
  • 3 tbsp of vegetables like peas or sweetcorn
  • A bowl of salad leaves or spinach
  • 7 cherry tomatoes

• Choose wholegrains with two of your daily meals
• Include beans and pulses regularly
• Choose nuts and seeds as snacks

These foods are rich in nutrients that help protect against cancer, and they're also a great source of fibre. Fibre helps keep us feeling fuller for longer, supporting a healthy bodyweight - and it can also help reduce the risk of bowel cancer.

Our standard sized meals contain two servings of vegetables, and almost all our meals contain beans, peas or lentils. You can find our highest fibre options here.

4. Limit 'fast foods'

Evidence shows that diets high in 'fast foods' and highly processed foods that are high in fat and sugar, and low in fibre, can lead to weight gain. This is partly because they are easy to overeat and not very filling. They also tend to be low in fibre and other beneficial nutrients that help to protect against cancer.

Try to make these foods (like crisps, biscuits, fried foods, cakes, sweets and pastries) the smallest part of your diet, and swap them for more fruits, vegetables, wholegrains, nuts and seeds.

5. Limit red and processed meat

There's strong evidence that processed meat can cause colorectal cancer, because it contains substances (some of which are created during cooking) that can harm the bowel. The advice is therefore to eat very little processed meat, if any. This includes:

• Ham
• Bacon
• Corned beef
• Some sausages, like chorizo and hot dogs
• Deli meats, like salami and pepperoni

Red meat includes any type of beef, pork, lamb or goat. The evidence for red meat being a cause of cancer isn't as strong as it is for processed meat, but it shows that red meat is probably a cause of cancer.

If you include red meat, the guideline is to limit how much you eat to no more than about three portions a week. This balances the benefits - it's a source of nutrients like protein, iron and vitamin B12 - with the risks. Three portions is equal to 350–500g (about 12–18oz) cooked weight, or 700–750g of raw meat. A portion looks like:

• A quarter of a 500g pack of mince
• A quarter-pound beef burger
• 3 thin slices of meat in your Sunday roast
• A sausage sandwich

6. Limit sugar sweetened drinks

Sugary drinks have been linked with weight gain - they're easy to consume and not very filling. For this reason, it's better to drink unsweetened drinks like water, or tea and coffee without sugar.

7. Limit alcohol consumption

Alcohol is part of many people's social lives, but there is strong evidence it can cause a range of cancers. Because there is no threshold at which the risk is zero, the WCRF's advice is not to drink alcohol at all for cancer prevention.

If you do include alcohol, stay within the UK guidelines for low-risk drinking:

• No more than 14 units a week (that's equal to 6 pints of 4% beer or 6 x 175ml glasses of 13% wine)
• Spread across three or more days
• With several drink-free days each week

8. Supplements aren't recommended for cancer prevention

There is no good evidence that supplements can reduce cancer risk. In fact, some high-dose supplements (such as beta carotene) have been found to increase it. So it's better to get your vitamins and minerals from food.

Supplements may be beneficial for specific groups - for example, people with iron deficiency, or older adults who need vitamin B12. If you want to take supplements, discuss this with a healthcare professional or your medical team.

9. For mothers: breastfeed your baby, if you can

Evidence shows that breastfeeding can protect against breast cancer in mothers, and support healthy growth in babies into childhood - though the WCRF recognises this isn't possible or right for everyone.

Experts think this is because breastfeeding changes hormone levels and alters cells in the breast in ways that may protect against cancerous changes.

10. After a cancer diagnosis, follow these recommendations, if you can

There is limited evidence around the impact of diet, nutrition, and physical activity in cancer survivors, with most of the research in those living with and beyond breast cancer. However, the WCRF's experts believe that the evidence that supports the Cancer Prevention Recommendations is relevant to cancer survivors too.

Following these guidelines can also help reduce the risk of other chronic conditions, including heart disease and type 2 diabetes, which can complicate cancer treatment and reduce survival.

And finally, it's worth remembering that not smoking and staying safe in the sun are also important factors in reducing your cancer risk.