Diet and exercise are the key, says Cancer Research Fund

Published on Monday 11 May 2009 21:21

WHEN it comes to reducing your risk of cancer, most people know not to smoke and to cover up in the sun.

But when it comes to other parts of our lifestyle, it can be difficult to judge how strong the evidence is for each claim we read in the paper or on the TV.

At World Cancer Research Fund, this is what made us decide a report was needed to look at all the evidence on the links between diet and physical activity and cancer and condense it into something people can incorporate into a daily routine.

It took five years and involved an independent international panel of experts and teams of researchers, who sifted through 500,000 studies and analysed the 7,000 most relevant. The panel came up with ten recommendations we believe are the best advice in the world about how you can reduce your risk of cancer.

The main finding was that eating a healthy diet, being regularly physically active and maintaining a healthy weight were the three best strategies.

According to the panel, a healthy diet is based around fibre-rich plant foods with only modest amounts of alcohol, salt and red meat, and little if any processed meat. Plant-based means eating a variety of fruits, vegetables, pulses and wholegrains every day.

When it comes to fruits and vegetables there is no evidence for a "magic bullet" to protect you against cancer. Those stocking up on berries or other "superfoods" may be wasting their time and money.

The evidence suggests fruit and veg probably reduce risk of cancer, but eat a wide variety, to get as many different nutrients as possible. The panel recommends you not to take dietary supplements.

Scientists estimate about a third of the most common cancers could be prevented just by eating healthily, exercising and maintaining a healthy body weight. That means every year in the UK, thousands of people are diagnosed with a case of cancer that could have potentially been prevented. Following these recommendations will also help reduce risk of other diseases such as heart disease and diabetes.

The report found red and processed meat increase risk of bowel cancer, which is why the panel recommended limiting red meat intake to 500g (cooked weight – about 750g uncooked) a week and avoiding processed meat. Salt consumption should also be limited to 6g per day because it probably increases risk of stomach cancer.

We also recommend avoiding sugary drinks and limiting consumption of foods that are energy dense, which means they have a lot of calories for their weight. This is important for cancer prevention because one of the report's main messages is the evidence that being overweight increases risk of cancer is stronger now than ever before. In fact, scientists now say, after not smoking, maintaining a healthy weight is the most important thing you can do for cancer prevention.

For example, we estimate about 14 per cent of bowel cancer cases in men and 16 per cent of breast cancer cases could be prevented if all of us were within the healthy weight range, a body mass index (BMI) of between 18.5 and 25.

This is why we recommend people aim to be as lean as possible without becoming underweight.

Making sure we are physically active is another way to maintain a healthy weight. The good news about physical activity is not only that it helps keep you trim, it can also reduce your risk of cancer in its own right. This means it has a kind of double-whammy effect for cancer prevention.

We recommend people are active at a moderate level or more for at least half an hour a day. But being active doesn't necessarily mean working out in the gym and can include things like brisk walking, cycling and even housework.

Also, you do not have to do it all in one go, so if you are walking ten minutes to the shops, that counts towards your total. Incorporating activity into your existing daily routine is in fact the best way of sticking to it in the long term.

It is important to emphasise that, with all our recommendations, it is not a case of all or nothing. If you are not active at all and doing half an hour a day seems daunting, you will still be making a positive difference by doing just ten minutes. If you have a bacon sandwich every day and don't want to give them up completely, think about having one a couple of times a week.

The evidence shows that whether we want to make big changes or little ones, we can make choices today that can reduce our risk of developing cancer in the future.

&#149 Lisa Cooney is head of education for World Cancer Research Fund. Cancer Prevention Week runs until Sunday.