Is red and processed meat really bad for me?

For processed meat -- such as ham, sausage, bacon and salami -- the evidence is clear. People who eat a lot of it have a 13 to 21% higher chance of colon or rectal cancer than people who eat little of it. For every extra 50 grams per day, the risk of cardiovascular disease rises by 26% and the risk of type 2 diabetes by 32%. The World Health Organization has therefore classified processed meat as a proven human carcinogen.

For unprocessed red meat -- such as steak and minced meat -- the picture is more nuanced. Population studies also find elevated risks: a 10 to 22% higher chance of colorectal cancer and an 11% higher chance of cardiovascular disease per 100 grams extra per day. But the association is smaller and less consistent. An analysis in Nature Medicine (2022) showed that the uncertainty margins are wide: the 'optimal daily amount' ranged from 0 to 200 grams. The association with stroke was not significant in that analysis¹.

All of this research is observational: associations measured in large groups of people, not direct proof of causation^2,3,4,5,6,7. People who eat a lot of meat may also live less healthily in other ways. This does not make the findings for processed meat any less relevant, but for unprocessed red meat it is an additional reason not to weigh the evidence more heavily than it deserves. Associations have also been found with lung, liver and kidney cancer, but that evidence is more limited than for colorectal cancer.

Red meat also provides something that is difficult to replace: essential amino acids, vitamin B12, iron and zinc. Anyone who sharply restricts meat without good alternatives such as legumes, dairy, eggs or supplements may develop deficiencies. For older adults this matters even more, because adequate protein becomes increasingly important with age. Moreover, the large population studies were conducted largely in people under 70, so the advice may not apply without qualification to the very oldest.

The best-supported step is to limit processed meat as much as possible. For unprocessed red meat, moderation is sensible, but people who eat little of it have less reason for concern, based on current research, than with the processed variety. Preferably replace meat with plant-based protein sources or fish, and make sure you get enough nutrients through those alternatives.