The document discusses research showing that smoking may help prevent canker sores. It notes that smokers and those who use smokeless tobacco or nicotine tablets get canker sores less frequently than non-smokers. Some patients reported getting canker sores after quitting smoking but saw them reduce again when they restarted smoking. While taking up smoking is not recommended, the document wonders if nicotine itself may help control canker sores and what chemical property it has that impacts canker sore formation.