It hits most afternoons around three: heavy eyes, foggy head, and a sudden interest in the biscuit tin. Another coffee or an energy drink gets you through, then you pay for it at bedtime.
There's a better routine. A cold, sharp raw kombucha instead of another sugar hit, with a gentle lift from the tea it's brewed with. And for the brain fog, creatine: best known in the gym, but now being studied for how it helps a tired brain keep going.
Part of it's your body clock, part of it's lunch, and part of it's sleep. Here's what the research says.
Your body clock has a natural lull in the early afternoon, which is why the slump turns up even on days you've slept well. A big, starchy lunch makes it feel worse.
Source: Monk, The post-lunch dip in performance, Clinics in Sports Medicine, 2005
A sugary snack or fizzy drink gives a quick lift that often ends in another slump. One can of full-sugar cola has 35g of sugar, more than the 30g UK adults are advised to have in a whole day.
Source: SACN, Carbohydrates and Health, 2015
Creatine helps cells recycle their energy, and your brain uses a lot of it. In a 2024 study, one high dose improved thinking speed and short-term memory in sleep-deprived adults, peaking around four hours later. A 2018 review found daily creatine may improve short-term memory in healthy people. Early days, but promising.
Sources: Gordji-Nejad et al., Scientific Reports, 2024; Avgerinos et al., Experimental Gerontology, 2018
Kombucha is brewed from tea, so it has a little caffeine, usually much less than a cup of coffee. Cold, sharp and fizzy, it's a proper reset that's less likely to keep you up than a third coffee.
Protein and veg first. Go easy on the white bread and pasta that make the dip feel deeper.
3 to 5g a day, any time, every day. It builds up in your body over a few weeks, so it's a habit, not a one-off hit.
Reach for a cold raw kombucha instead of the biscuit tin or a third coffee. The ginger ones have the most kick.
A quick walk round the block or a few flights of stairs gets you going faster than any drink.
The most researched supplement there is. Most people know it from the gym, but your brain runs on the same energy system as your muscles, which is why researchers are now studying creatine for focus and mental fatigue. Vegetarians and vegans tend to have lower levels, as it's mostly found in meat and fish.
Plain, unflavoured, one ingredient. It stirs into water, a smoothie or your kombucha.
How Kev takes it: 5g every morning in water or a smoothie. Every day, not just the bad ones.
A kick in the right direction.
Kev's own four.
Creatine and friends. They count towards the box deal.
Mix any 6 for 5% off, 12 for 10%, 24 for 15%. Kombucha and creatine both count.
It's not an energy drink, and we won't pretend it is. It has a little caffeine from the tea, and a cold, sharp drink is a proper reset. Swapping it for a sugary snack also skips the sugar dip that follows.
A little, from the tea, and it varies by maker. Usually much less than a cup of coffee. If you're sensitive, have it before mid-afternoon.
No. Your brain uses the same energy system as your muscles, which is why researchers are studying it for focus and mental fatigue. Vegetarians and vegans often have lower levels, because creatine is mostly found in meat and fish.
It's one of the most studied supplements there is. 3 to 5g a day is the usual amount. If you have kidney problems, are pregnant or take medication, check with your GP first.
This page is general information, not medical advice. Research into creatine for focus and mental fatigue is still early. If you're constantly exhausted, see your GP, as ongoing tiredness can have medical causes. If you have kidney problems, are pregnant or take medication, check with your GP before taking creatine.