Building the research evidence base to inform policy action

The global burden of cancer

Cancer causes one in six deaths worldwide and has overtaken cardiovascular disease as the leading cause of death in many parts of the world. Additionally, more people are living with and surviving cancer than ever before, at least in part because of earlier detection and the increasing success rates of treatment for some cancers. In 2012, there were an estimated 32.6 million cancer survivors around the world.

Yet, despite the statistics, many cases of cancer are entirely preventable. Lifestyle factors such as diet and physical activity, play a key role in influencing cancer risk. A critical driver underpinning the increases in cancer rates globally is the astonishing increase in the numbers of people living as overweight or obese over the past 40 years or so.

There are many factors contributing to this, but we know that lifestyles featuring little exercise and diets high in processed foods containing fat, starches or sugars are fuelling overweight and obesity, resulting in the dramatic increases in cancer rates worldwide.  

It’s easy to forget that behind the statistics are people, with families and friends who love them. Cancer doesn’t just affect the person with the disease, its impact radiates out, affecting and changing lives forever.

Overweight and obesity as cancer risk factors

The central role of overweight and obesity in cancer is highlighted in the new WCRF/AICR Expert Report – Diet, Nutrition, Physical Activity and Cancer: a Global Perspective, which provides a comprehensive analysis of the worldwide body of evidence on preventing and surviving cancer through diet, nutrition and physical activity.

The report builds on the achievements of our First and Second Expert Reports, published in 1997 and 2007 respectively. Through its updated Cancer Prevention Recommendations, it provides strengthened evidence for a comprehensive package of behaviours that, when taken together, represent the most reliable guidance available for living healthily to reduce cancer risk.

Some of the main findings are that:

• Being overweight or obese is a cause of at least 12 cancers, five more than WCRF findings a decade ago.
• Regularly drinking sugar-sweetened drinks increases cancer risk, because it causes weight gain, overweight and obesity.
• Being physically active helps protect directly from three cancers, and also helps maintain a healthy weight, further reducing cancer risk.
• A healthy diet featuring whole grains, vegetables, fruit and legumes  and low in red and processed meat reduces cancer risk.
• Drinking alcohol is strongly linked to an increased risk of six cancers – this is one more than WCRF findings a decade ago.
• Breastfeeding protects mothers from breast cancer and their babies from becoming overweight and obese in later life.

A blueprint to beat cancer

The aim of our Cancer Prevention Recommendations is to help people make healthy choices in their daily lives to reduce their risk of cancer. They provide a blueprint to beat cancer that people can trust, because they are based on evidence that has now proved consistent for decades. Importantly, a growing number of large population studies have shown that the more closely people follow a dietary pattern close to the 2007 recommendations, the lower their risk of developing cancer and also other major non communicable diseases.

The importance of the research evidence base

Collectively, the three WCRF/AICR Expert Reports constitute a significant contribution to the research evidence base on cancer prevention. This evidence base is vital to help develop and inform policy on cancer prevention and control. The importance of research evidence was acknowledged and recognised in the landmark Cancer Resolution adopted at the 2017 World Health Assembly. WCRF International and the Union for International Cancer Control (UICC) worked together and independently to advocate for the Cancer Resolution. Its adoption by governments from across the world reaffirmed cancer control as a critical health and development priority, providing countries with guidance for change across a broad range of health promotion and risk factor reduction areas.

Now, a year on from the adoption of the Cancer Resolution, the Third Expert Report adds to the research evidence base. The report also features a policy and public health implications section, highlighting the critical role and responsibility of governments to develop and implement effective policies to create an environment that will enable people and communities to follow the recommendations as part of their daily lives.

The Third Expert Report and its Summary are freely available at dietandcancerreport.org. Join us in sharing the report and recommendations, and help change cancer statistics for the better.