Most brain fog clears when you fix sleep, hydration, lunch, movement and screen habits, in that order, for three weeks. If it doesn't, get a blood test and talk to your doctor about medication and mood. Supplements go last, if anywhere.
Where to start
If you've read our page on what causes brain fog, you know there's usually a reason. This page is the other half: what to actually do, in the order that gives you the biggest return first. Do these in sequence for three weeks before you spend money on anything.
Sleep, for real
Not "try to sleep more." A fixed wake time seven days a week, which anchors your body clock more than a fixed bedtime does. No screens in bed, because the light and the content both delay sleep. Caffeine finished by early afternoon; it has a half-life of five to six hours, so a 4pm coffee is still a quarter-coffee at 10pm. A cool, dark room. If you snore or wake unrefreshed, ask about sleep apnea. Two weeks of this clears more fog than everything else on this page combined.
Water and a lunch that doesn't crash you
A glass of water when you wake up and one with every meal gets most people out of the mild dehydration they live in. For lunch, protein and something with fiber, and less of the white carbohydrate that spikes blood sugar and drops you into the 3pm hole. It sounds trivial. It's not; the afternoon fog most office workers accept as normal is largely lunch and dehydration.
Move
A brisk twenty-minute walk raises blood flow to the brain immediately (more than any supplement does, including the ones sold on that basis) and improves mood and sleep on top. If you can't walk, anything that gets you slightly out of breath works. The best time is whenever you'll actually do it.
Reduce the load
Stress fog is real and it doesn't respond to willpower. What it responds to is fewer things demanding attention at once. Write the list down so it's not circling in your head. Say no to something. Take a proper break at lunch rather than eating at your desk. If you're carrying something heavy, talk to someone about it, because a mind that's processing a problem in the background has less left for the foreground.
Break the screen habit
Attention is a muscle and a phone is a machine for fatiguing it. Checking it every few minutes fragments concentration for hours afterward. Put it in another room while you work. Turn off every notification that isn't a person. Take a five-minute break every hour where you look at something far away and don't read anything. These feel like small things and they're not.
Check the medicine cabinet and the blood
If the fog started after a new medication, that's the first suspect and worth a five-minute conversation with your pharmacist. If none of the above has cleared it after three weeks, get a blood test for iron, B12, vitamin D and thyroid, and tell your doctor honestly about your mood, because depression presents as fog more often than people expect.
A routine, if you want one
Wake at the same time. Water. A short walk or some movement before work. Protein at breakfast. Phone in another room during focused work, breaks every hour. A proper lunch with protein and fiber. No caffeine after 2pm. A screen-free wind-down. Bed at roughly the same time. That's the whole anti-fog protocol and none of it is for sale.
Where supplements fit
At the end, if at all. A caffeine-free circulation capsule like Memocept won't fix sleep, stress, dehydration or a B12 deficiency, and those are what's causing most fog. If you've done the list above and want to try it as a low-risk extra, fine, with the usual caution about blood-pressure medication. But it goes last.