HOW can meat, a food that we’ve been eating for millennia, a food that made the human race what it is, one of the most nutrient-dense sources of sustenance available, be bad for us?

In evolutionary terms, this assumption defies reason, yet the European Commission is reviewing its funding of promotional campaigns for red meat and processed meat on the grounds that its consumption might be linked to cancer. What’s the evidence for this proposition?

Some epidemiological (observational) studies have posited an association between intake of red and processed meats and slightly increased incidence of colorectal cancer. But epidemiological research is the weakest standard of scientific evidence. Based on extrapolation of statistics, it is more prone to bias than robust randomised controlled trials or intervention studies.

Saying that meat is “associated” with cancer is quite different from stating that meat causes cancer.

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A person who eats meat three times a day might rarely exercise, suffer from stress, eat lots of ultra processed food, work at an unhealthy job, and munch on confectionery to get them through the day.

These “confounding factors” affect the results, even after statistical adjustment. This is known as “residual confounding”. In epidemiological diet studies, it’s too easy to blame meat for the health damage wreaked by the pappy bun, sweet sauces, chips fried in bad oil, and sweet drinks that are commonly consumed alongside it, particularly if that confirms or supports the researchers’ prior beliefs or values.

Epidemiological data is further compromised by what is known as “healthy user bias”. We are repeatedly told to avoid eating red and processed meat, and healthy middle class people may well have done so, while their less healthy working class equivalents may not. This doesn’t mean that meat per se is the culprit, as opposed to the person’s generally less healthy lifestyle.

Even the epidemiological case against meat is contradictory. In many countries, notably in Asia and Africa, meat consumption is associated with better, not worse health.

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The 2018 PURE study, which follows 218,000 participants, in 50 countries, on five continents concluded that, “our results show that dairy products and meat are beneficial for heart health and longevity”.

Other epidemiological studies have found that meat eating is protective against another sort of cancer, melanoma, and reported that the incidence of colorectal cancer in UK meat eaters and vegetarians is not significantly different.

This is why the World Health Organisation (WHO) and the International Agency for Research on Cancer (IARC) concludes that “consumption of red meat has not been established as a cause of cancer”.

Nevertheless, the WHO/IARC has classified the potential hazard red meat presents as Group 2A, a substance that is “probably carcinogenic to humans”. That sounds alarming, but let’s look at this rating system more closely.

Sunlight is considered to be a class 1, therefore more serious, hazard. Yet we know that sunlight is mostly beneficial for us. It makes life on earth possible. It is our most efficient way of building up vitamin D, a vitamin that is crucial for immunity, bone health, and much more.

Rather than attempting to build a shaky statistical case against red meat we should apply common sense. That very important figure in British nutrition, surgeon captain Thomas Latimer Cleave, whose 1966 book, the Saccharine Disease, first identified the negative health effects of consuming over-refined foods and sugar, put it best: “For a modern disease to be related to an old-fashioned food is one of the most ludicrous things I have ever heard in my life”.

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I give more credence to the idea that potential jeopardy attaches to consumption of industrial, ultra-processed meats because they contain modern, chemical food additives.

Bacon and ham is commonly cured with nitrates or nitrites, which have been pinpointed by some scientists as carcinogenic. But the same risk applies to many food additives, titanium dioxide, for instance, the colour that makes chewing gum and cake icing shiny white.

There’s a cool headed stance to adopt. Avoid, or at least limit foods that have been ultra-processed with chemical food additives (E numbers).

Where possible, choose meats that are simply cured with salt, air, and time, such as Parma ham. I wouldn’t eat nitrite-cured bacon daily but I’ll eat it now and then.

In toxicological terms, it is the dose that makes the poison, not the substance in itself.