The World Health Organization describes stress as the ‘health epidemic of the 21st century’, but our understanding of it begins with the work of Hans Selye, the Hungarian–Canadian endocrinologist.

Later known as ‘the father of stress’, his early research involved injecting mice with extracts of various organs and observing atrophy of the lymphoid tissue, adrenal enlargement and peptic ulcers. He initially thought he had discovered a new hormone, but later realised that this was the uniform response to every irritating substance he injected. He subsequently coined the term ‘stress’. In a note to Nature in 1936, Selye described three stages of alarm, resistance and exhaustion: responses that are well known to those grappling with winter pressure demands or research and education deadlines!

The feature articles in this issue of The Endocrinologist delve into various aspects of stress, from mitochondria (described in Gabriele Saretzki’s piece on oxidative stress) to man (as Adnan Agha relates in his account of burnout in healthcare professionals).

In his transatlantic article, Bruce McEwen focuses on the biological impact of experiences throughout the life course, illustrating that hormones play a key role by acting on the brain as well as the rest of the body.

We explore the importance of circadian clocks for stress, sleep and well-being with David Ray. Chris John describes how he has used stress as a learning and teaching platform! Sirazum Choudhury, Tricia Tan and Bernard Khoo argue for the need to redefine the cortisol stress response.

Katherine White highlights emotional stress as a trigger factor for adrenal crisis. We gain an insight into how glucocorticoids can restore balance during stress, in an article by Giorgio Caratti, Pauline Pfänder and Laura Matthews. Finally, Mark Gurnell has written a brilliant piece on stress in the world of finance, and endocrine influences on financial markets.

I do hope that perusing the winter issue of The Endocrinologist will help alleviate some of the stress associated with this time of year!

With warmest wishes and season’s greetings

Amir Sam