"Not everyone exposed to infectious diseases gets sick from them. Your vulnerability to illness often has to do with the strength of your immune system and your exposures, stress level, and habits." - Dr Daniel Amen, psychiatrist and author of Memory Rescue.

There’s something magical about summer. Long, bright evenings, the warmth of the sun on your skin, and the promise of holidays, picnics, and outdoor adventures. But while we’re busy enjoying ourselves, there’s a less welcome guest that sometimes slips into the party: the brain fog that can follow a viral or bacterial infection.

If you’ve ever found yourself struggling to remember simple things, losing your train of thought mid-sentence, or feeling like your brain is wading through treacle after being unwell, you’ve experienced it. Brain fog isn’t just “feeling a bit tired.” It can make it harder to concentrate, process information, or make decisions, and it can leave you feeling strangely disconnected from your usual self.

The trouble is, viruses and bacteria don’t just affect the parts of our body we expect - like our lungs, throat, or stomach. They can also trigger inflammation in the brain or disrupt the chemical messengers that help brain cells communicate, which is why your thinking can feel so fuzzy long after the fever has passed.

But, while we can’t put ourselves in a bubble to avoid every germ, we can take smart steps to reduce our risk of picking them up - especially over the summer holidays when we’re mixing more, travelling more, and exploring new places.

Here are some simple ways to keep the summer months healthy for yourself and your family:

1. Enjoy The Sun - But Not Too Much

One of the simplest brain-supporting steps you can take this summer is to make sure you’re getting enough vitamin D. This sunshine vitamin plays a key role in your immune system’s ability to fight off infection, which in turn protects your brain from the inflammatory effects that can trigger brain fog. Just 10-20 minutes a day of sun exposure to the skin, can help your body make its own supply - provided you catch the rays at safe times, ideally before 11 a.m. or after 3 p.m., when the sun is gentler.

It’s worth noting that while sunscreen is essential for protecting your skin from harmful UV rays, it also blocks the UVB light your body needs to make vitamin D. That doesn’t mean ditch it - it means finding a balance: enjoy short, safe bursts of sun before you apply sunscreen, then protect your skin for longer periods outdoors.

2. Cover Up On Countryside Walks

If you’re heading out for a country walk or camping in nature, especially in areas where deer roam, be mindful of ticks. These tiny creatures can carry bacteria that cause Lyme disease, which can bring on long-term symptoms, including brain fog, if untreated. Wear long sleeves and trousers when walking through tall grass or wooded areas, and check your skin (and your children’s) after your walk.

If you spot a tick, remove it promptly using a fine-tipped tweezer, pulling steadily without twisting, and wash the area well. Then see a doctor as soon as possible.

3. Stay Hydrated

On hot summer days, it’s easy to get caught up in activities and forget to drink enough water—but staying hydrated is one of the simplest ways to support your immune system and keep brain fog at bay. Your brain is around 80% water, and even mild dehydration can affect your focus, memory, and mood. It can also put extra strain on your body, making it harder for your immune defenses to do their job.

Aim to sip water regularly throughout the day rather than waiting until you feel thirsty, as thirst is a sign you’re already on your way to dehydration. If plain water feels boring, try infusing it with slices of lemon, cucumber, or fresh mint for a refreshing twist. Carrying a reusable water bottle when you’re out and about is a simple way to keep this habit going - whether you’re at the beach, hiking in the hills, or exploring a new city.

4. Take Time to De-Stress

It’s easy to think of the immune system as something separate from our mood, but in reality, the two are closely linked. Chronic stress can suppress immune function, making it harder for your body to fend off the viruses and bacteria that can cause brain fog. That’s why one of the best things you can do for your brain this summer is to give yourself permission to relax, laugh, and play.

Whether it’s joining in a silly game with your children, sharing a meal with friends who make you belly-laugh, or trying something new just for the fun of it, these joyful moments flood your body with feel-good chemicals. They lower stress hormones, boost immune activity, and strengthen the very defences that protect your brain. So this summer, treat laughter as essential medicine and make space for light-hearted moments. You’ll be building resilience in both mind and body.

Build Fun Memories

Summer should be a time for making special memories, not losing them in a haze of brain fog. By taking these small but intentional steps, you’re not only protecting your body - you’re protecting the incredible organ that allows you to think, create, and connect with the people you love most. And that’s a summer investment worth making.