Healthy eating and cancer

Our diet, how active we are, and our weight can all affect our risk of cancer.

Scientists still do not completely understand the link between diet and the risk of developing cancer. Some foods may increase our risk of cancer, but others may protect us. For example, research suggests that eating more fibre may reduce the risk of certain cancers. Eating a lot or red and processed meat may increase the risk of bowel cancer. 

Research also shows that being overweight increases the risk of getting some types of cancer. Our weight depends on what we eat and how much physical activity we do.

Other things can also affect our weight, such as:

• medical conditions
• our genetic makeup
• our environment
• our mental well-being.

A healthy, balanced diet and regular exercise can help us keep to a healthy weight. This can help reduce the risk of some cancers and is also good for our general health. There is also evidence that drinking alcohol can increase the risk of getting some cancers. If you want to drink alcohol, follow the national guidelines. 

We have answers to some common questions about food and cancer.

In the video below, dietitian Jane Clarke talks about how eating healthily can help maintain your wellbeing and reduce the risk of some cancers. She also answers frequently asked questions about diet and cancer.

View the video without BSL interpreter on our YouTube Channel.

It is not healthy to be overweight or underweight.

Eating less food than your body needs can make you underweight. This can affect your health.

Eating more food that your body needs can make you overweight. Many people in the UK are heavier than the recommended weight for their height. Being overweight can lead to health problems such as:

• heart disease
• high blood pressure
• diabetes
• a higher risk of complications if you need surgery
• a higher risk of certain types of cancer including bowel, kidney, womb and gullet (oesophagus) cancer
• a higher risk of breast cancer, if you have been through menopause.

There are different reasons for gaining weight, including your diet and not doing enough physical activity. Some types of cancer treatment, such as hormonal therapy or steroids, can also lead to weight gain.

If you are overweight, having healthy eating habits and increasing your physical activity may help with weight loss and have health benefits. Losing 5% of your body weight can be one of the best ways to reduce your risk of cancer.

Reducing your weight may also help reduce the risk of some cancers coming back.

Body mass index (BMI) uses the measurement of your height and weight to help find out if you are a healthy weight. A healthy body weight is also dependent on your:

• sex
• age
• ethnicity
• muscular build.

BMI scores are different for older people, some ethnic groups and people who are very muscular. For example, a BMI result cannot tell if someone is carrying too much fat or a lot of muscle.

The NHS website has a BMI calculator. Your GP or nurse can also work out your BMI for you.

If you are concerned about your weight, ask your GP or a dietitian for advice and support. Dietitians can give you advice about healthier food choices that still make you feel full. Fruit and vegetables are better than high-fat or high-sugar snacks, such as biscuits and cake.

Losing weight is a process. It can take some time. It is important to eat a healthy, balanced diet to make sure you get all the nutrients you need to keep your body healthy. It is reasonable to aim to lose about 0.5 to 1kg (1 to 2 pounds) a week.

It is not advisable to follow a very low-calorie or restricted diet to lose weight. This can lead to rapid weight loss, but when you start to eat more normally again, evidence shows that you may gain the weight back.

For some people, losing weight can be difficult. In some situations, doctors may prescribe weight loss injections.

• The following tips may help you keep to a healthy weight:
• Choose healthy foods with lots of fruit and vegetables and less fat and sugar. 
• Check the food labels of packaged foods.
• Eat only as much food as you need. This depends on how active you are.
• Eat only when you are hungry. If you eat for comfort when you are not very hungry, try to distract yourself with another activity.
• Try to be physically active. It can help if you find a form of exercise you enjoy. If you are not normally very active, ask your GP for advice. Start off any exercising gently and build up gradually.

We have more information about what can help with weight gain. 

Resources

• We have some answers to common questions about physical activity and cancer.
• We have more information about making changes to your diet.
• You may find it helpful to use our food and activity planner.

People may worry that eating healthily can cost a lot of money. But healthy eating does not need to be expensive. You can still eat well on a small budget. 

• Choose good-value protein sources such as frozen chicken thighs, budget cuts of meat, tinned fish, baked beans, tinned beans, lentils, chickpeas and Quorn™ or soya products.
• Plan your meals and make a list before you go shopping – this will help you buy only what you need.
• Do not go shopping when you are hungry. This will help you be less likely to buy extra snacks. 
• Try  value brands. These are often as good as more expensive brands.
• Make sure ‘special offers’ really offer you good value. Compare the price per gram, which is usually listed on the shelf label. 
• Remember that loose fruit and vegetables may be cheaper than packaged items.
• Choose seasonal fruits and vegetables, as these are often less expensive. 
• Only buy foods you can store safely. If something is on offer and you can store it or freeze it safely, stock up on that item.
• If you can, shop towards the end of the day when fresh items may be reduced. 

The British Dietetic Association has recipes and more information to help you cook and eat healthily while saving money. The NHS has useful tips on how to eat well for less.