A new study claims that red meat causes 1 in 10 early deaths. First off, an "early death" is defined as dying before age 75, so that's not exactly young. Rob Lyons analyzes the study and decides that not only is red meat pretty safe, but also that other major lifestyle decisions seem to have little impact on longevity.
The authors claim that 9.3 per cent of deaths in men and 7.6 per cent of deaths in women could be avoided by eating little or no red meat. To put that into some back-of-an-envelope statistical perspective: multiplying that 9.3 per cent by the 20 per cent who actually died shows that about 1.8 per cent of red-meat eaters would die by the time they were 75 because of their meat-eating habit. Even if that claim were absolutely accurate (and even the authors call it an estimate), would you really give up your favourite foods for decades on the slim possibility of an extra year or two of old age?
A serious problem with the present study is that while the researchers excluded anyone who had a heart problem or cancer at the time the study started, there were some pretty important differences between the groups examined. In both the male and female groups, at the start of the study the people who ate the most red meat were also about twice as likely to be diabetic and took much less exercise. The men in the high red-meat group were also three times as likely to be smokers and drank much more, too. (Women who like their red meat also liked booze and fags more than their burger-dodging sisters did, but the differences weren't as large.)
There was also a clear trend in total calories consumed per day for both men and women. The low red-meat group consumed far fewer calories each day (1,659 for men and 1,202 for women) then the highest red-meat group (2,396 for men and 2,030 for women). These are enormous differences.
It's pretty amazing that someone who eats so badly and exercises so little only has a 1.8 percentage point increase in his chance of dying before age 75. Does that make diet and exercise pretty much a waste of time?
Final thought: what's the most dangerous risk factor?
The thing most likely to determine whether you live or die - apart from old age, of course - is whether you are male or female. One way to illustrate this is to add up the total number of years that people in each group lived and divide it by the number of people who died. The group of women who ate the most processed meat suffered one death for every 124 person-years lived. The group of men who ate the least processed meat suffered one death for every 89 person-years lived. Being a man is much more dangerous than eating bacon, it would seem.