Comments found on Reddit:
Burnt/charred material on the outside of food is a chemically complex of compounds made in the process of "burning" something. Because of the nature of the process of cooking-where high energy and local dehydration occur, some compounds that form will be carcinogens. Carcinogens are chemicals that when eaten do some damage to DNA in the cells of your body.
Depending on the food and how burnt the food is, amount of carcinogen will vary.
Whether cancer results is probabilistic and depends on carcinogen load. Hypothetically eating more burnt food will increase your risk, but the amount by which your risk increases is much less well characterized than say exposure to X-rays or nuclear radiation.
Some people would consider it a negligible concern like a choice just the way some people consider smoking cigarettes to be a choice. Burnt food is probably less carcinogenic than cigarettes but would affect different tissues like the stomach/colon more than the lungs.
Just listed to Harald Hausen, who won a Nobel for linking HPV and cervical cancer, give a talk about this yesterday. While the compounds in burnt food have been shown to cause DNA damage, it isn't clear that eating burnt and barbecued foods actually increases colon cancer incidence. A few interesting points from his current research:
- Mongolia has one of the highest rates of red meat consumption in the world, and the meat is usually barbecued. They also have one of the lowest per capita colon cancer rates.
- Bolivia is a similar story, high red meat consumption, low cancer rate.
- Consumption of grilled or burnt fish/salmon/vegetables does not seem to be correlated with colon cancer, and in the case of fish may even play a protective role.
- Pork consumption is very high in China, but they have a middling rate of colon cancer. The evidence points toward specifically bovine meat consumption being correlated with cancer. So you should be ok with bacon.
More importantly, average life expectancy in Mongolia is less than 70 years, with nearly half the population under the age of 25. Since colorectal cancer is primarily seen in older adults, they're obviously going to have less of it. akula457