In this part of Meaty Misconceptions, I want to address two health concerns, which in addition to concerns about heart disease which I covered previously, are often given as reasons to remove meat from the diet – the risk of developing cancer and Type 2 diabetes. This may be in part driven by media headlines such as “Two slices of bacon a day increases diabetes threat by 50” and “50g of processed meat a day increases the risk of colorectal cancer by 18%”. So, I also want to highlight why we should be wary of attention-grabbing headlines when it comes to nutritional research highlighted in mainstream media. I want to encourage you to apply a critical eye to the content beneath the headline.
What’s behind the headlines?
A lot of the research which is cited to prove these links and the media headlines that ensue, like much of the nutrition research, it is based on what is known as epidemiological data. This is data gathered from large populations of people tracked over many years, which researchers then review to look for patterns. Whilst patterns can reveal associations, they do not prove causation, but the way in which the results are reported often leads people to infer that A causes B. Additionally, the data typically comes from inaccurate Food Frequency Questionnaires that require individuals to estimate their average food and drink intake over the last 12 months. The categories of meat also often include hamburgers, meat sandwiches and lasagna with no portion size. Consequently, what the researchers categorise as both processed and unprocessed red meat is confounded by the inclusion of carbohydrates in how the meat was consumed and the amount in any individual serving. All of this calls into question the accuracy of the data which is further emphasised by total calories figures at levels that are hard to believe.
Epidemiological studies also refer to the relative risk of developing a disease as opposed to the absolute risk because it sounds more impressive but can be misleading. As an example, to illustrate this the World Health Organisation (WHO) claimed that each 50g of processed meat eaten daily increases the risk of colorectal cancer by 18%. This sounds very significant, but this is a relative risk number. The incident rate of bowel cancer in the UK is around 47 people per 100,000 so an increased relative risk of 18% takes that to 55 people per 100,000. However, the absolute risk is still low because 55 per 100,000 represents a risk less than 1%. Similarly in the studies linking meat consumption and diabetes, the absolute risk was 0.42% so even though relative risk was reported as 62% it still represents a very small absolute risk. And that’s if these associations can be proved to translate into causation which it cannot through epidemiological research.
Do all scientists agree?
In 2015 a WHO working group completed an evaluation of the carcinogenic risk to humans of red and processed meat consumption. Despite the limited amount of robust evidence, the summary report claimed that ‘consumption of red meat is probably carcinogenic to humans’ and that the ‘consumption of processed red meat is carcinogenic to humans’. They also placed processed red meat in the same group of carcinogenic substances as tobacco and asbestos, making dramatic headlines across the world. Many medical professional and scientists critiqued the WHO findings, including those who were part of the working group (!), because of the inadequacy of the research on which it was based. In fact, 23 cancer experts from 8 countries had previously examined the same science and concluded that the data was inconsistent and underlying mechanisms linking meat to cancer were unclear.
Other large population studies in Europe and the US have found no association between unprocessed red meat and any cause of death, including CVD or cancer. Unlike many earlier studies, these studies explored health outcomes associated with unprocessed and processed meats separately. The authors concluded that the findings from these studies provide good support for recommending both unprocessed red and white meats as part of a healthy balanced diet. However, despite these opposing conclusions and the reviews of the WHO report published in highly reputable scientific journals that assert that ‘the current epidemiological and mechanistic data have not been able to demonstrate a consistent causal link between red meat intake and chronic diseases, such as cancer’ the misconception that eating red meat will give you cancer remains.
Who’s behind the research?
When it comes to nutritional research, we also want to examine who is behind the research to identify any biases that might be inadvertently skewing the approach taken, the statistical analysis applied and the way results are presented. For example, many the studies showing an association between meat consumption and cancer have been undertaken by the Harvard School of Public Health using the same population data.
This research has been carried out under the leadership of Professor Walter Willett, a well-known advocate for vegetarian diets since the 1990s. By contrast, a study published in 2025 using a similar approach to investigating the same data as the Harvard studies came to very different conclusions. They observed no differential associations between mortality risk from all causes, cancer, and cardiovascular disease and dietary proteins derived from plants and animals. In fact, their analysis found that animal protein intake was modestly associated with a lower cancer mortality risk, and they concluded that their findings, along with decades of clinical trial evidence, support the inclusion of animal protein as part of a healthy dietary pattern. Interestingly, the research was conducted by McMaster University but funded by The National Cattlemen’s Beef Association, although the authors reported that the sponsor had no role in its design, analysis, or interpretation.
What can we conclude?
It is easy to be confused by media reporting that make the results of studies appear more meaningful than they are. However, it is worth remembering that because most studies show extremely small risks based on weak evidence it is virtually impossible to say with any certainty that any particular food can cause a specific disease or indeed prevent it. Several scientists are now in agreement that underlying issues such as insulin resistance and inflammation are key drivers of a number of chronic illnesses such as cancer and Type 2 diabetes, as well as heart disease and dementia. Consequently, from a nutritional perspective, we need to eat an overall dietary pattern that minimises these drivers rather than including or excluding specific foods. We should place an emphasis on real food, including meat, that provides the vast array of nutrients we need, keeps our blood sugar stable, and supports gut health, and avoid being swayed by catchy headlines.
Finding our way through the myriad of conflicting information and health claims to make the right decisions about what to eat is, at best, tricky and, at worst, seemingly impossible. So, if you’re not sure of the right thing to do and are looking for more help, I’d love to support you to uncover the food and lifestyle choices that are right for you.
Please use the link below to book in for a complimentary 30-minute Health & Energy review