Does burning toast make it unhealthy?

Probably not, but nobody really knows since burned toast isn’t high on the research agenda.

Cooking muscle meats — beef, pork, fowl, and fish — above 400 degrees Fahrenheit creates chemicals that are not present in uncooked meats, according to the National Cancer Institute. Researchers found that people who ate meat medium-well or well-done had three times the risk of stomach cancer, compared to those who ate their beef rare or medium-rare.