There might be some factors which the study is failing to control for, but from the link in the grandparent
Included in the analysis were 448,568 men and women without prevalent cancer, stroke, or myocardial infarction, and with complete information on diet, smoking, physical activity and body mass index
The study seems to control for the more obvious associated factors.
Also, the full text states that the consumption of red meat is associated with an increase in mortality when controlling for the confounders assessed in their study, with processed meat being associated with a greater increase, but poultry not being associated with an increase in mortality.
The problem is that the choice to eat differently itself is potentially a confounding factor (people who pick particular diets may not be like people who do not do so in very important ways), and any time you have to deal with, say, 10 factors, and try to smooth them out, you have to question whether any signal you find is even meaningful at all, especially when it is relatively small.
The study in particular notes:
[quote]Men and women in the top categories of red or processed meat intake in general consumed fewer fruits and vegetables than those with low i...
There's a lot of background mess in our mental pictures of the world. We try and be accurate on important issues, but a whole lot of the less important stuff we pick up from the media, the movies, and random impressions. And once these impressions are in our mental pictures, they just don't go away - until we find a fact that causes us to say "huh", and reassess.
Here are three facts that have caused that "huh" in me, recently, and completely rearranged minor parts of my mental map. I'm sharing them here, because that experience is a valuable one.