Short answer: The afternoon slump, or "post-lunch dip", is partly built into your body clock. Sleepiness naturally rises in the early to mid-afternoon, even if you skip lunch, and a big carb-heavy lunch can make it worse. The best fixes are a lighter lunch, daylight and movement, a short nap if you can take one, and a small dose of caffeine early in the afternoon. Keep the dose small so it doesn't affect your sleep that night. One piece of Zuum Everyday Energy Gum has 30mg of caffeine.
It's 3pm. You've read the same email three times, your eyes are heavy, and the biscuit tin is calling. You're not lazy: the afternoon slump is one of the most predictable things your body does.
Why the afternoon slump happens
Sleep researcher Timothy Monk reviewed the evidence in The post-lunch dip in performance. He found:
- The dip is real, but not universal. It shows up in some measures of performance and in some people more than others.
- It's linked to rising sleepiness at that time of day, as part of your natural daily rhythm.
- It still happens if you skip lunch, and even when people don't know what time it is. So it's not just about food.
- A high-carbohydrate lunch makes it worse.
- Morning people may feel it more.
On top of that, most of us add our own extras: a short night's sleep, a long meeting in a warm room, and hours of sitting still.
Six ways to beat the slump
1. Eat a lighter lunch
A big bowl of pasta or a burger and chips is more likely to leave you sluggish. Aim for a balanced lunch with protein, vegetables and some carbs, rather than a huge carb-heavy meal.
2. Get outside
Daylight and a short walk are simple ways to wake yourself up. Even 10 minutes outside after lunch helps break up a long stretch of sitting.
3. Drink water
Mild dehydration can leave you feeling tired and flat. Keep a bottle on your desk. If you've been training or sweating, an electrolyte drink can help too: see our hydration and electrolytes guide.
4. Take a short nap (if you can)
A short nap of under 15-20 minutes can reduce sleepiness without leaving you groggy. Keep it short, as longer naps can leave you feeling worse when you wake up and affect your sleep that night.
5. Try a "caffeine nap"
This one sounds odd but it's backed by research. In a driving simulator study, sleepy people had 200mg of caffeine followed straight away by a short nap of under 15 minutes. The combination worked better than either on its own:
| Treatment | Driving incidents (vs placebo) |
|---|---|
| Placebo | 100% |
| Caffeine alone | 34% |
| Caffeine + short nap | 9% |
The idea is that caffeine takes a little while to kick in, so you nap while it's being absorbed and wake up as it starts working. Even people who only dozed lightly got the benefit.
6. Have a small dose of caffeine, early
If you don't have time for a nap, a small dose of caffeine is the next best thing. You don't need much: a study of low doses of caffeine found as little as 12.5mg improved attention and mood. Read more in low dose caffeine and focus.
Caffeine options for the afternoon
| Option | Caffeine | Things to know |
|---|---|---|
| 1 piece of Zuum Everyday Energy Gum | 30mg | No drink needed. Easy to keep the dose small |
| Cup of black tea | About 50mg | A gentle option |
| 2 pieces of Zuum Everyday Energy Gum | 60mg | For a bigger lift |
| 1 sachet of Zuum Everyday Energy Powder | 60mg | Also has 250mg sodium, 200mg potassium and 60mg magnesium |
| Energy drink (250ml) | About 80mg | Usually high in sugar |
| Espresso coffee | About 145mg | A big dose late in the day |
Watch the timing
The catch with afternoon caffeine is your sleep. In a study on caffeine and sleep, 400mg of caffeine taken 6 hours before bed still significantly disrupted sleep. A poor night means a worse slump tomorrow, and the cycle repeats.
So:
- Have your afternoon caffeine early, ideally before 2-3pm if you go to bed around 10pm.
- Keep the dose small. A 30mg piece of gum is a lot gentler on your sleep than a 145mg espresso.
- Count all your caffeine. Food Standards Australia New Zealand recommends adults have no more than 400mg a day and 200mg in a single serve. See how much caffeine is in coffee, tea and energy drinks.
Frequently asked questions
Why do I get tired at 3pm?
Sleepiness naturally rises in the early to mid-afternoon as part of your body clock. A big carb-heavy lunch, a short night's sleep and sitting still for a long time can all make it worse.
What is the post-lunch dip?
It's the drop in alertness many people feel in the early afternoon. Research shows it happens even if you skip lunch, so it's linked to your body clock rather than just food.
What is a caffeine nap?
It's having caffeine and then taking a short nap of under 15 minutes straight away. In a driving simulator study, the combination reduced sleepiness more than caffeine or a nap alone.
What is the best thing to have for the afternoon slump?
Start with daylight, movement and water. If you need caffeine, a small dose is usually enough. One piece of Zuum Everyday Energy Gum has 30mg of caffeine.
What time should I stop having caffeine?
Aim for at least 6 hours before bed. For most people that means no caffeine after mid-afternoon.
The bottom line
The afternoon slump is part of how your body works, but you don't have to give in to it. Eat a lighter lunch, get some daylight, drink water, take a short nap if you can, and keep any afternoon caffeine small and early. If you want a quick, measured lift without another coffee, try a piece of Zuum Everyday Energy Gum.
Read the study: Monk TH (2005), The post-lunch dip in performance, Clinics in Sports Medicine 24(2):e15-23. Abstract on PubMed.
Want to learn more about how Zuum works? Read the science behind Zuum, browse energy gum, or see our FAQs.
