A meta-analysis of data found that dietary patterns high in unprocessed red meat (beef, pork, lamb, and venison), and especially processed meat (like deli meats, bacon, ham, hotdogs, sausage, and jerky), are associated with higher risk of developing type 2 diabetes. The prospective study (which cannot prove cause and effect) included nearly 2 million participants from countries around the world.
Although higher red meat intake was associated with higher type 2 diabetes risk, replacing processed meat of any kind with unprocessed red meat or poultry was associated with lower risk.
This study does not prove that eating red or processed meat causes diabetes. For example, it may be that the foods used to replace the red or processed meat conferred the health benefit. But the association it found does suggest one more reason to avoid or limit processed meats and limit intake of red meat in favor of plant proteins like beans and tofu, fish/seafood, low-fat or fat-free dairy, and some eggs and poultry.