Numerous studies have suggested a link between the consumption of processed meat and an increased risk of certain types of cancer. The International Agency for Research on Cancer (IARC), which is part of the World Health Organization (WHO), has classified processed meat as a Group 1 carcinogen. This classification means that there is sufficient evidence to conclude that processed meat consumption can cause cancer in humans.
The main concern with processed meats is that they typically contain nitrates and nitrites, which are chemicals used in the curing process. When consumed, these compounds can form nitrosamines in the body, which are known carcinogens.
This is why there are so many "nitrate-free" options of bacon available for purchase today.