We’ve all felt the Monday blues at some point. There’s a distinct feeling of sluggishness, unease, and creeping anxiety that hits. Much of that is in your mind; but your body feels it too. Now, a new study suggests that this feeling could have a significant impact on your health.

A large study of older adults in England has found that anxiety experienced specifically on Mondays leaves a lasting mark on the body’s stress system. Participants who reported feeling anxious on a Monday had significantly higher levels of cortisol (the body’s main stress hormone) up to two months later, compared to those who felt anxious on any other day of the week.

And here’s the kicker: it didn’t matter whether they were working or retired.

Ew, Mondays

The study was led by sociologist Tarani Chandola from the University of Hong Kong. It gathered data from 3,500 adults, all over the age of 50. They were asked how anxious they felt the day before and what that day had been.

But the researchers didn’t just rely on what people report. Instead, they took samples of hair to monitor cortisol levels.

Just like how trees hold clues to past climate in their tree rings, your hair holds a record of some chemicals and hormones in your body. Since it grows about a centimeter a month, a short strand can reveal accumulated stress hormone exposure over time. And at the highest levels (what scientists call the 90th percentile) the difference was stark: people who felt anxious on Mondays had 23% higher cortisol than those who didn’t find Mondays different from any other day.

The association held even after controlling for factors like age, sex, medications, and even whether people dyed their hair. And perhaps most tellingly, the effect was just as strong in retirees as it was in those still working.

In other words, the “Monday blues” can become biologically embedded, with chronic stress hormone dysregulation posing long-term cardiovascular risks.

“Mondays act as a cultural ‘stress amplifier,’” said Professor Chandola. “For some older adults, the week’s transition triggers a biological cascade that lingers for months. This isn’t about work — it’s about how deeply ingrained Mondays are in our stress physiology, even after careers end.

Not Just Minor Anxiety

The link between stress and disease is well established. If Monday anxiety happens regularly, it can easily descend into chronic stress, which can fuel a cascade of health problems: high blood pressure, diabetes, obesity, and weakened immunity to count just a few. Cortisol, the key stress hormone, plays a starring role in all of them.

This isn’t the first study to highlight Monday’s hidden toll on our bodies. Serious heart attacks are more common on Mondays. In fact, cortisol levels have been found to be consistently higher on Mondays (and Tuesdays) than the rest of the week. What makes the new “anxious Monday” research stand out is its precision: by analysing hair cortisol, it reveals that the stress impact of Monday lingers biologically for months

The fact that this effect doesn’t fade with retirement is all the more concerning.

This suggests that the health risks of Monday anxiety are more than just an occupational hazard. They might reflect a broader failure to adapt to the rhythms of modern life. For those particularly vulnerable, Monday could be the start of a weekly cycle of physiological wear and tear that adds up over decades.

So What Can You Do?

Science doesn’t offer a pill that can eliminate stress; at least not yet. Instead, the same advice that usually carries through the rest of the week (staying physically active, being mindful, having a healthy diet) are also useful in dealing with the Monday blues.

If Mondays hit you especially badly, you can try turning Sunday evenings into a ritual of calm, not chaos. Power down screens earlier and prep your clothes, meals, or to-do list, which helps you feel more in control of the day. Then do something that’s not about productivity: a walk, a bath, a book, music you actually listen to. Signal to your brain that the weekend doesn’t have to end in tension.

If you can, don’t schedule your hardest meetings first thing. Ease into the day with low-stakes tasks. Even a short walk outside or a few minutes of focused breathing can reset your nervous system. Think of it as buffering your biology. Try building habits you can follow week after week so that your mind knows what to expect.

Lastly, it’s usually a good idea to listen to your body. Chronic dread of Monday might be a sign your workload, workplace, or lifestyle needs rethinking. What your body’s telling you with hormones, your mind might already know: something’s out of sync.

Stress will probably never vanish entirely, but you shouldn’t accept it as background noise. If Mondays are leaving a mark on your health, maybe it’s time to start marking them differently.

The study was published in the Journal of Affective Disorders.