How a healthy diet can benefit you

What we eat influences our health. Up to 10% of cancers may be linked to diet. Research indicates that being overweight may contribute to 7 % of cancers in women. A lack of fruits and vegetables may also be responsible for 6% of cancers in men. Although a lot of research still needs to be done to understand which substances increase our risk of developing cancer, we know what types of foods can keep us healthy.

A balanced diet and physical activity have many health benefits. They can help reduce the risk of heart disease, strokes and diabetes. They can also help us maintain a healthy weight which can reduce the risk of developing certain types of cancer.

If you’re trying to lose weight, it’s important to make sure you still get all the nutrients you need. Your diet should include fruits and vegetables and you should try to limit fat and sugar. Keeping active will also help you manage your weight. Your GP or dietitian can advise you on your ideal weight and offer you support.

Why a healthy diet is important

Experts think that up to 1 in 10 (10%) cancers in the UK may be linked to diet. There’s a lot of research being done into which types of food may affect our risk of developing cancer.

One report showed that a lack of fruit and vegetables in the diet may contribute to about 6 out of 100 (6%) cancers in men. Being overweight may contribute to about 7 out of 100 (7%) cancers in women. There are many other reasons why people are overweight, but an unhealthy diet and lack of physical activity are often factors.

However, we still don’t understand exactly how diet influences the risk of developing cancer. There are many reasons for this, mainly because both cancer and diet are complex.

Eating habits are very different from person to person.

Our diets are made up of many types of foods, which in turn are made up of thousands of different substances. Some of these substances may increase our risk of cancer but others may protect us. And the influence on what we eat, and our risk of cancer, is likely to take many years, or even decades, to have an effect. So trying to find out how diet affects our risk of developing cancer is complicated.

For now, we do know which types of food help keep us healthy. And we know that a balanced diet and regular exercise helps us keep to a healthy weight, which can help reduce the risk of developing some cancers.

Many people find making this positive choice helps give them back a sense of control. It can also help you feel that you’re doing the best for your health. Thinking about what and how much you drink is part of this too.

Eating well and keeping to a healthy weight will help you maintain or regain your strength, have more energy, and have an increased sense of well-being. It can also help reduce the risk of new cancers, heart disease, strokes and diabetes.

After cancer treatment, some people have a higher risk of developing other health problems, such as diabetes, heart disease or osteoporosis (bone thinning). If you’ve been told that you may be at an increased risk of any of these conditions, it’s especially important to follow a healthy diet to help prevent them.

How diet can help reduce your risk of cancer

How diet can help reduce your risk of cancer

Macmillan Dietitian Keynes explains how we can help advise on what to eat during and after cancer treatment.

About our cancer information videos

How diet can help reduce your risk of cancer

Macmillan Dietitian Keynes explains how we can help advise on what to eat during and after cancer treatment.

About our cancer information videos


Keeping to a healthy weight

It's not good to be either underweight or overweight. Eating too much can make you overweight, which can lead to health problems such as heart disease, high blood pressure or diabetes. Not eating as much food as your body needs can also affect your health.

If you're underweight, or find it difficult to eat enough to maintain your weight, you can find helpful advice in our sections The building-up diet and Recipes.

Many people in the UK are heavier than the recommended weight for their height. And unfortunately, certain types of treatment for cancer, such as hormonal therapies or steroids, can cause weight gain. Losing weight can be difficult, but keeping a healthy body weight is one of the best ways to reduce your risk of developing cancer. There's more information and advice about managing your weight.

Being overweight increases the risk of many types of cancer, including cancers of the bowel, kidney, womb, oesophagus (gullet) and breast cancer in women who have been through the menopause.

There's also evidence that women who have breast cancer after the menopause may be able to reduce their risk of the cancer returning by keeping to a healthy body weight after treatment.

Try to keep your weight within the normal range for your height. Your GP can advise you on your ideal weight. If you're concerned about your weight, get in touch with your GP or a dietitian for advice and support.

Be patient with yourself. Losing weight is a gradual process. It’s important to eat a balanced diet to make sure you get all the nutrients you need to keep your body healthy. It’s reasonable to aim to lose about 0.5–1kg (1–2lbs) a week.

  • Only eat as much food as you need according to how active you are. You may need to discuss your calorie needs with a dietitian.
  • Eat a balanced diet, with lots of fruit and vegetables, and less fat and sugar.
  • Be more physically active.

You can read more about physical activity and cancer treatment, or order our Move more information to find out more about how to be more active and the benefits of doing so.


Back to Healthy eating

Healthy eating

A balanced diet will provide everything you need to keep your body healthy. It will contribute to your well-being.

How to maintain a healthy diet

Knowing about food types and limiting your alcohol intake can help you maintain a healthy diet.

How your body uses food

Our bodies need foods from different groups to keep us healthy.

Commonly asked questions about diet

You may have questions about diet and cancer. We have answered some of the most common ones.