Diet and cancer

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An unhealthy diet increases your risk of cancer

The food and drink that you consume regularly make up your diet. It is hard to study the effects of diet on cancer because your diet includes foods that may protect you against cancer and foods that may increase your risk of cancer. The genes you inherit can also affect the way your diet influences your cancer risk.

Researchers have to carry out very large studies to see which specific foods influence our risk of cancer. Many of these studies are ongoing and are starting to provide us with clearer answers.

Looking at current scientific evidence, it is reasonable to link parts of our diet with cancer of the bowel, breast, mouth, oesophagus (foodpipe) and stomach

Eat your way to good health

Your diet has a powerful effect on your health, including your chance of getting cancer. But we don’t blame you if you feel confused by all the different messages you hear about what to eat and what not to eat. When all is said and done, you can reduce your risk of cancer by eating a healthy, balanced diet. This means that your diet is:  

  • Rich in fruit and vegetables
  • High in fibre
  • Low in red and processed meat, saturated fat and salt

You can start to eat your way to good health at any time, from childhood to old age. No matter when you start, you will begin to be healthier. And eating your way to good health doesn’t just protect you against cancer and other diseases. It will also provide you with lots more energy and the key ingredients for looking and feeling great at any age.

The five fundamentals of healthy eating

The five fundamentals of healthy eating will set you on the right path to reducing your cancer risk and eating your way to good health. It is also important to remember that a healthy diet will help you to maintain a healthy body weight, which can itself reduce the risk of many cancers.

The five fundamentals of healthy eating are:

  1. Go bananas for fruit and veg
  2. Fill up on fibre
  3. Red alert on red and processed meat
  4. Think before you chew the fat
  5. Don’t take it with a pinch of salt

Click here for much more information on the five fundamentals of healthy eating

Keep a food diary

If you want to take a good look at your diet, try writing down what and how much you eat and drink for a week. We have prepared a daily healthy living diary (PDF, 320KB) to help you do this. If possible, update your diary after every meal and snack and don’t leave it until the end of the day.

At the end of the week, compare your food diary to the guidelines we set out in the 5 fundamentals of healthy eating and note where you can improve your diet. Keeping a food diary can also help you to control your weight and watch your portion size.

Download and print our sample food diary here (PDf, 320KB)

Look at the label

Be careful when reading claims on food packaging as they can be misleading. For example, ‘light’ or ‘reduced fat’ food may have less fat than a similar product but they can still be high in fat or sugar. Looking carefully at food labels can help you to make better choices. Safefood has produced this booklet of guidelines to help you (pdf, 233KB).

Dietary supplements and ‘superfoods’

The best source of nourishment is food and drink, not dietary supplements. You can get all the nutrients you need from a healthy, balanced diet. Unless your doctor or dietician suggests supplements, you do not need them.

Likewise, there are often stories in the media about specific foods or so-called ‘superfoods’ that are meant to be particularly good for us. But you should not rely on superfoods to reduce your risk of cancer. Nothing beats a healthy, balanced diet.

Healthy recipes

101 Square Meals

101 Square Meals is a low-cost, healthy-eating cookery book supported by MABS, Safefood and the HSE. You can:

Little Steps

For more delicious, healthy recipes, visit Little Steps. The Little Steps campaign has been developed by the Health Service Executive and Safefood in consultation with a wide range of obesity and health experts and stakeholders. 

Revised 2013, next revision 2015

Date Last Reviewed: 
Thursday, October 31, 2013
Date Last Revised: 
Wednesday, June 3, 2015