Afternoon energy crashes: why they can feel harder in your 40s
2:30 pm. Up to now, the day has been great. But now I feel tired, I have no energy, I can't focus — and I find myself in the kitchen in front of the coffee machine, pondering whether to get another coffee or just call it quits and go home. That's what often happened to me when I was still working in corporate.
If you know what I'm talking about — and if it has been getting worse over the past few years — it may be time to take a closer look. It's not a discipline or motivation problem, and you're not alone. The question is: is it just a normal dip, or is something making it worse?
A dip is normal — a severe crash is worth noticing
A dip in the afternoon is completely normal. Our bodies follow certain rhythms, and the afternoon dip is a normal part of our circadian rhythm. Lunch can contribute to it, but it happens even without eating anything for lunch. So a mild dip is something to expect. A complete crash — maybe even a daily one — that disrupts your work and other activities is different. There are different factors that can contribute to that crash, and they are worth looking into.
Could stress and your daily rhythm be involved?
Cortisol often gets a bad rap, but it's one of the hormones that get us going in the morning, waking us up and making us alert. The normal curve peaks in the morning, then gradually declines throughout the day. In the afternoon the curve is already lower — hence a dip is possible. If you have been under a lot of stress for a longer period of time, or have been sleeping badly, that curve can flatten so that it's already very low in the afternoon, turning the dip into a hole. Waking up tired, depending heavily on caffeine, feeling exhausted during the day but "tired but wired" at night can also be signs of a flattened cortisol curve. But keep in mind: these signs are not a diagnosis. They can also simply mean that you have been under a lot of stress, or that your sleep has not been very good. (If you're also waking up around 3am, those can be two sides of the same shifted rhythm — I wrote about that here.
Could lunch be amplifying the dip?
To begin with, lunch does not create the circadian dip in the afternoon — but it can contribute to it and make it more noticeable. Very large meals, meals made up of mostly refined carbohydrates, meals low in fiber or protein, or eating too quickly can all make the dip worse. And since we're all unique, we all have different glucose responses. Not all post-lunch dips are blood sugar crashes, but it definitely makes sense to take that into account. Do I repeatedly have a stronger afternoon dip after certain meals? Is it stronger after large lunches, or after a lot of refined carbs? Do I feel better in the afternoon after a lighter lunch? Try to notice how you feel after certain meals: jot down what you ate and how you feel a few hours later. It makes sense to start by noticing — not by eliminating things right away.
Could last night's sleep be the factor?
Even if you felt alert and awake in the morning, sleep could still be a factor. Morning light, caffeine and the natural momentum we have in the morning can mask poor sleep and carry you through — at least until the afternoon. If you don't sleep enough, or your sleep is fragmented — waking up again and again during the night — it can reduce your alertness during the day. So an afternoon dip can expose sleep deficits that have been accumulating. Signs to look out for: the crash changes from day to day, it's worse after short, restless or interrupted nights, and it feels much lighter after a night of genuinely restorative sleep.
Why it may feel harder in your 40s
In perimenopause, a lot of factors can affect your daytime energy. Hormones start to fluctuate, and that can lead to more fragmented sleep, night sweats and hot flashes, a fluctuating and changing cycle, mood changes, a gradual change in body composition and insulin sensitivity — just to name a few! These changes and symptoms are highly individual, but they can have strong effects on our bodies and our minds, and influence our energy levels. Routines or meals that used to work for us can now leave us feeling tired. Of course, hormones can be part of the picture — but they don't have to be.
Look for what makes the crash stronger
If you have noticed these crashes: rather than trying to change everything at once, it makes sense to start noticing. Start observing things like:
the exact time the crash begins
what and when you ate
sleep duration and sleep quality
caffeine timing
your stress levels
where you are in your cycle, if that's still relevant for you
You're looking for what the crash tracks — the clock, the plate, or the night. A week of noticing is a start, but two to three weeks can give you really good clues as to what is going on.
A guided way to do exactly that
If you would like some guidance for this kind of noticing experiment, you can try my free 7-Day Cortisol Experiment — a 10-page PDF guide with one simple daily focus around your morning, day and night. You jot down what you're tracking and how it affects your mood, energy and sleep. After just a week you get the first clues; after 2–3 weeks the patterns become even clearer.
If you'd rather have an app to help you, I built My Inner Balance for exactly that. Try it — it's free on the App Store.
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A gentle note: persistent, heavy exhaustion that doesn't respond to rest deserves a doctor's visit — especially if the fatigue is new or severe. Iron deficiency, anemia, thyroid problems, sleep disorders and problems with blood sugar regulation can all contribute to fatigue and are worth ruling out.
