Cinnamon, renowned for its aromatic flavor, represents one of the most widely used spices worldwide. Cinnamon is also considered beneficial to human health with therapeutic potential for treating various diseases, ranging from diabetes and cancer to neurodegenerative diseases. However, the mechanisms underlying cinnamon's health benefits remain elusive. It is also unclear whether cinnamon has any role in aging. Using C. elegans as a model, here we show that feeding worms cinnamaldehyde (CA), the active ingredient in cinnamon oil, prolongs longevity. CA also promotes stress resistance and reduces β-Amyloid toxicity in a C. elegans model of Alzheimer's disease. Mechanistically, CA exerts its beneficial effects through mTORC1 and autophagy signaling. Interestingly, CA promotes longevity by inducing a dietary restriction-like state without affecting food intake, suggesting CA as a dietary restriction mimetic. In human cells, CA exerts a similar effect on mTORC1 and autophagy signaling, suggesting a conserved mechanism. Our results demonstrate that dietary cinnamon promotes both lifespan and healthspan and does so by regulating mTORC1 and autophagy signaling.