Recent research has shown that regular consumption of breakfast cereal is associated with lower stress levels and reports of better physical and mental health. The present study examined this issue using an objective indicator of stress, salivary cortisol. The results showed that stress was associated with higher cortisol levels and daily consumption of breakfast cereal was associated with lower cortisol levels. Although it was not possible to rule out all the alternative explanations of the association between breakfast cereal consumption and cortisol, analyses did show that the effect could not be accounted for by general health or nutritional status. The effects of breakfast cereal consumption and stress were also independent, which shows that the effects of breakfast found here cannot be due to stress buffering. Further research manipulating the nutrient content of the breakfast cereal is now required to provide further information about the mechanisms underlying this effect.