Step 4: forming evidence-based guidance and recommendations

There’s a four-step method by which we arrive at new guidance and recommendations, within the CUP Global process. This page explains the 4th and final stage.

Cancer Prevention Recommendations

The Expert Panel uses the evidence judgements from step 3 to make recommendations (and sometimes guidance) for the public. Currently, our cancer prevention recommendations focus on cancer prevention, these were developed from the evidence judged for the Third Expert Report.

The Panel uses its judgements on the findings from the evidence reviews to make recommendations. The risk of other diseases, as well as cancer, is also modified by diet, nutrition and physical activity. This includes diseases related to nutritional deficiencies, cardiovascular diseases and other non-communicable diseases.

When making the cancer prevention recommendations, other recommendations on the prevention of these diseases made by authoritative international and national organisations from around the world were therefore taken into account.

Evidence which is judged as ‘strong’ (either ‘convincing’ or probable’) is normally strong enough to support a recommendation, while judgements of ‘limited suggestive’ are generally not. Each conclusion on the likely causal relationship between an exposure and an outcome forms part of the overall body of evidence that is considered during the process of making cancer prevention recommendations.

There are individual recommendations on weight and physical activity as well as particular aspects of diet and nutrition. The recommendations focus on foods and drinks rather than on nutrients or other bioactive constituents.

The recommendations are intended to work together and be adopted as a lifestyle package. Individual recommendations are likely to be less effective if followed in isolation but together they promote an overall way of life – a healthy pattern of diet and physical activity – that is conducive to the prevention of cancer, other non-communicable diseases and obesity.

In addition to our cancer prevention recommendations on diet, nutrition, physical activity and body weight, it is extremely important not to smoke and to avoid other exposure to tobacco, excess sun exposure and long-term infections that can case cancer.

Recommendations and guidance after a cancer diagnosis

The literature on how diet, nutrition, physical activity and body weight influence long-term health for people living with and beyond cancer is, despite growth in recent years, in its infancy compared with that for cancer incidence.

Researching the modifiable behaviours that might influence health-related outcomes among this population is also highly complex.

Unlike the evidence on cancer incidence, the Expert Panel judged the strength of much of the evidence in those living with and beyond cancer (to date reviews on colorectal cancer and breast cancer have been carried out) as ‘limited’ and this hampered them from being able to develop recommendations.

Despite the challenges, it is important that people living with and beyond cancer can access sound information. Therefore, along with recommendations for how future research can address these challenges, it is important to maximise how the currently available evidence is used.

We have done this through the development of guidance statements developed with input from experts (scientists, health professionals and patients). These differ from clinical guidelines and our recommendations – which are developed based around a strong evidence base.

Guidance is a way of providing information for healthcare professionals and patients in areas where the evidence is less strong based on the judgement criteria. However, it is noteworthy that a substantial body of evidence is reviewed by the Panel to be able to develop this guidance.

This process enables us to provide people living with and beyond cancer with information based on the best available evidence while taking into account its limitations.

Recommendations for future research

As well as developing public health recommendations and guidance for people living with and beyond cancer, a key activity is providing direction for future research based on the learnings from the evidence reviews and judgement process. This should support researchers to effectively address limitations in the evidence and move the field forward.

This is especially true for the cancer survivorship literature, where it was apparent that more of the same types of data or studies would be unlikely to strengthen our understanding of the influence of modifiable behaviours related to diet, nutrition, physical activity and body weight on outcomes for people living with and beyond cancer.

Improved research would allow for stronger evidence conclusions, which could then be turned into information for the public.

A visual explanation of how we develop our recommendations

At the World Cancer Congress 2024 in Geneva, our Senior Research Interpretation Officer, Sarah Kefyalew, gave a rapid-fire presentation, explaining the process to reach our recommendations.

> Download the poster that accompanied this presentation (PDF 204KB)

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