There a new medical report that’s been in the news recently, published by BioMed Central:
In its conclusions it states that Processed meat consumption increases the chance of mortality and that 3.3% of premature deaths could have been prevented by a reduction in the consumption of processed meat.
To clarify, what they class as processed meat is anything that hasn’t been simply sliced off an animal and cooked. So this includes ham, bacon, sausage, pasties, pies, salami etc. (Interestingly, they classify red meat as “beef, pork, mutton/lamb, horse, goat” )
The report is based on information that has been gathered from almost half a million people spread across europe aged between 35 and 70 at the start of the 12 year sampling period. Various methods were used to gather, estimate and calculate various dietary intakes and lifestyles, and information about underlying cause of death was gathered from the 26,344 deaths that occurred during the time. However the data collection processes are not consistent between countries, and in some cases even seem to be very sparse, with follow ups to the original data gathering taking place years after the initial survey.
So the data is incomplete, incongruous and in many cases calculated, but one of the main things that concerns me about the quality of the conclusions are the associated datasets.
For instance, the report mentions that groups that consume more than 160g of processed meat a day are likely to be smokers and that groups that consume more than 160g of red meat a day are likely to be heavy drinkers. Whilst steps may have been taken to factor these things into the results, they will still taint the data as the associated lifestyle choices are also detrimental to health.
It’s like releasing a report that says people earning a certain amount for a salary are more likely to die in plane crashes, but then saying that pilots salaries fall within that band as well.
What is certain is that there is a correlation between the amount of processed meat consumed and mortality, what is uncertain are the factors that cause the correlation. For instance, consider what is classed as processed meat, Bacon, Sausages, Pork Pies, Pasties, Ham etc. Now consider how those items are prepared and served.
Bacon and Sausages are both quite often fried in their own fat and served in carbohydrate rich bread or part of a high cholesterol breakfast. Pork pies and pasties are both encased in carbohydrate and fat rich pastry. Even Ham is usually served in bread and how often will that be with butter or mayonnaise? How much of the correlation between processed meat consumption and mortality relies on the cooking and serving of the meats themselves?
This brings into question whether the correlation is more closely linked to a lifestyle rather than the product. Given that, according to the report, someone eating large quantities of processed meat will quite probably be a smoker, drinker and do little activity, is it any surprise that they are more likely to suffer ill-health because of their lifestyle than someone who eats very little processed meat, but leads an active lifestyle and doesn’t smoke?
What the report does not do is prove that 3.3% of premature deaths could have been prevented by reducing processed meat intake to 20g a day (a thin slice of bacon) it merely highlights that people whose lifestyle supports the consumption of large quantities of processed meat are more likely to die earlier.
What we should take from this is not that idea that processed meats are bad and we should immediately stop eating pork pies and bacon sandwiches (I just had a shudder go down my spine even thinking about that) but that this is another indicator that unhealthy lifestyles are more likely to be bad for your health, who’d have thought it?
As an aside part of me immediately classed the report as completely useless when I found it contained the comment:
We estimated that 3.3% (95% CI 1.5 to 5.0%) of deaths could be prevented if all participants had a processed meat consumption of less than 20 g/day.
What are they saying here? if everyone in the world limited themselves to only one rasher of bacon a day then 3.3% of the population would be immortal? You cannot prevent death, you can only postpone it, it is going to happen sometime regardless of how much bacon you eat.