Cancer Nutrition and Lifestyle Guidelines from WCRF

In this article we’re going to delve into the evidence-based recommendations provided by the World Cancer Research Fund and the American Institute for Cancer Research, and look at the recommendations, particularly for those living beyond breast cancer.

These cancer guidelines are constantly being updated as new research is published. It’s the only programme of its kind and its evidence is trusted by oncology experts worldwide. The aim of these recommendations is to give you the most up-to-date evidence so that you can make lifestyle choices that reduce the risk of cancer recurrence and improve overall health.

The impact of the recommendations for those with breast cancer

While there isn’t evidence to say that diet and exercise can alter the clinical course of breast cancer, there is evidence that what you eat, and levels of body fatness and physical activity can reliably predict important outcomes from breast cancer.

The WCRF recommends that all those living beyond cancer should receive nutritional care and physical activity guidance from trained professionals. After a diagnosis of cancer, you are advised to follow the cancer prevention recommendations as far as possible after your main treatment is finished.

The WCRF recommendations

1. Be a healthy weight

There is strong evidence that greater body fatness can cause many cancers, including breast cancer. Maintaining a healthy weight throughout life is one of the most important ways to protect against cancer and this applies to both before and after a diagnosis.

The WCRF recommends: Keep your weight as in line with the BMI healthy range as you can (18.5–24.9kg/m²) and avoid weight gain throughout adulthood.

2. Be physically active

There is strong evidence that physical activity protects against a range of cancers, including breast cancer. Regular exercise not only helps with weight management but also supports immune function, improves digestion and gut health, and reduces inflammation.

The WCRF recommends: Be at least moderately physically active and follow or exceed national guidelines. Limit sedentary habits.

3. Eat a diet rich in wholegrains, vegetables, fruits and beans

There is evidence that dietary patterns which include these are linked to a lower risk of cancer, as well as being helpful in weight management.

The WCRF recommends:

- 30g fibre per day from plant foods.

- Include wholegrains, non-starchy vegetables, fruit, and pulses (legumes), such as beans and lentils in most meals.

- Aim for at least 5 portions/servings (>400g) of non-starchy vegetables and fruit every day.

- - If you eat a diet based on starchy roots and tubers (cassava, sweet potatoes, yams, and taro), then aim to also eat some non-starchy vegetables, fruit, and legumes regularly if possible.

4. Limit consumption of ‘fast foods’, and other processed foods high in fats, starches or sugars

There is strong evidence that diets containing greater amounts of fast foods and other highly processed foods are causes of weight gain, being overweight, and obesity.

Fast foods include burgers, fried chicken, chips, and high-calorie drinks and shakes. Highly processed foods include processed meat products (e.g., sausages, hot dogs, and chicken nuggets), crisps, mass-produced bread, breakfast cereals, and sweetened yogurts. Foods in this category also include cakes, pastries, biscuits, cookies, confectionery, and energy drinks.

Highly processed foods tend to be appetizing, high in energy, affordable, easy to access, and convenient to store. We don’t need to exclude these foods totally from the diet, but because they are often lower in micronutrients and fiber, and usually have additives, stabilizers, preservatives, and sweeteners, they ideally shouldn’t be eaten daily in high amounts.

The WCRF recommends:

- Limit consumption of ‘fast foods’ and other processed foods high in fat, starches, or sugars.

5. Limit consumption of processed and red meat

It’s recommended that we avoid eating processed meats where possible. Processed meat includes foods like sausages, ham, bacon, and some other preserved and processed meats. There is strong evidence that processed meats are a cause of bowel cancer.

The WCRF also recommends reducing intake of red meats, as there is strong evidence that high intakes of red meat is a cause of bowel cancer. This doesn’t mean you need to cut red meat totally out of your diet, as there are plenty of nutritional benefits of including red meat in your diet if you like it. Meat can be a valuable source of protein, iron, zinc, and vitamin B12.

The WCRF recommends:

- If you eat red meat, limit consumption to no more than about three portions per week. This is equivalent to about 350-500g cooked weight. Consume very little, if any, processed meat.

6. Limit consumption of sugar-sweetened drinks

There is convincing evidence that consumption of sugar-sweetened drinks is a cause of weight gain, overweight, and obesity, especially when consumed in large portions. This in turn increases the risk of many cancers.

The WCRF recommends:

- Limit the consumption of sugar-sweetened beverages.

7. Limit alcohol consumption

The WCRF recommends, if possible, to not drink alcohol at all. There is strong evidence that consumption of alcoholic drinks is a cause of many types of cancers, including breast cancer.

The evidence shows that it doesn’t matter what type of alcohol it is; even small amounts can increase the risk of several cancers.

The WCRF recommends:

- For cancer prevention, it’s best not to drink alcohol.

8. Do not use supplements for cancer prevention

The WCRF recommends that we should aim to meet our nutritional needs through diet alone; that we do not need to use supplements for cancer prevention. For most people, the right food and drink is more likely to protect against cancer versus supplements.

The WCRF recommends:

- High-dose dietary supplements are not recommended for cancer prevention. Aim to meet nutritional needs through diet alone.

Every individual circumstance is different and so in different situations, a supplement or several may be clinically appropriate. Personalised advice from a dietitian is recommended, and supplements should always be discussed with a pharmacist, as herbal and dietary supplements may interfere with existing medications.

9. Breastfeed your baby, if you can

The WCRF recommendation is to breastfeed, where possible, any baby you have as there is strong evidence that breastfeeding protects against breast cancer in the mother and promotes healthy growth in the infant. The WCRF endorses the advice of the World Health Organisation, which recommends that, where possible, infants are exclusively breastfed for six months, and then for up to two years or beyond alongside appropriate complementary foods.

Putting it into practice - what does a healthy diet look like?

What does a diet look like considering the WCRF recommendations? What sort of proportions should we be aiming for in a meal or across a day? What does a healthy portion size look like? This article aims to answer these important questions.

In the UK, we have the Eatwell guide, and many people will be familiar with its recommendations and graphics. However, Perci’s expert dietitians prefer to refer to the Canadian food guide, which they feel more accurately describes the current global dietary recommendations.

For portion sizes, we prefer to use a hand as a guide rather than weighing out foods. The British Heart Foundation has a useful article and infographic to help you learn more about this.

Five principles of a healthy diet

A healthy diet is about balance and variety. It includes a wide array of nutrient-rich foods that provide our bodies with the essential macronutrients, vitamins, minerals, and antioxidants that we need to thrive. Here are some key principles to keep in mind:

1. Fill at least half of your plate with colourful fruits, vegetables, and salads, to provide fiber for digestive health as well as a range of micronutrients.

2. Choose wholegrains over refined white grains for sustained energy and gut health benefits. These should make up about a quarter of your plate.

3. Opt for lean proteins like fish, poultry, tofu, beans, chickpeas, and lentils. Aim for a quarter of your plate to be protein, which is important for building and repairing tissue, supporting muscle health, and keeping you feeling full and satisfied.

4. Include healthy fats from sources like oily fish, nuts, seeds, avocados, and olive oil. These are essential for brain function, hormone production, and overall health.

5. Cook with ingredients that are additive and preservative-free wherever possible, to minimise the number of processed foods you eat.

By aiming for a rainbow of colour and variety across your day and week, you can nourish your body, support your recovery, and enhance your overall quality of life.

You may also find it useful to look at the British Heart Foundation information on sugar, salt, and fat.

Ultimately, eating healthily is about balance. If you aim to make healthier choices 80% of the time, use the remaining 20% to have more food freedom to find a balance where you can enjoy all the foods that you love within your diet.