If Mondays feel like a battle, science says you’re not imagining it — and your body might be paying the price.
A new study from the University of Hong Kong reveals that anxiety experienced specifically on Mondays is linked to a long-lasting spike in cortisol, the body’s primary stress hormone. The study, published in the Journal of Affective Disorders, tracked over 3,500 adults over 50 in England and found a striking 23% increase in cortisol levels in those who reported Monday anxiety, even one to two months later.
Why does this matter? Chronically elevated cortisol can wear down your immune system and increase the risk of serious health issues like heart disease, chronic anxiety, and fatigue.
“This isn’t just about one bad morning,” explains Stanford neuroscientist Robert Sapolsky. “The expectation of stress can trigger a stronger cortisol response than the stress itself.”
Interestingly, even retirees showed elevated cortisol levels, indicating that Monday stress is more about mental and biological patterns than just workplace dread.
“There’s something effortful about Mondays,” says Modupe Akinola, a professor at Columbia Business School. “You have to reboot—physically and mentally—and your body responds like it’s gearing up for battle.”
So, how can you combat the Monday effect? Akinola suggests creating a “stress inventory” on Sundays: list what’s bothering you and plan how to manage it. This intentional approach can turn background anxiety into something you can actually control.
Bottom line: That Sunday night dread may be more than just a mood. It could be silently spiking your stress hormones and impacting your health. Taking small steps to prepare mentally can make a big difference for both your mind and body.