Stress and Brain Fog: How Stress Affects Brain Function + Nutritionist Tips to Clear Your Mind

Have you ever noticed that when you're stressed, your mind feels slower, foggier, or just not quite “you”? There’s a biological reason for that. Stress doesn’t only affect your mood - it can actually alter your brain chemistry and reduce your ability to think clearly.

The good news is that your brain is incredibly adaptable. With the right nutrition and daily habits, you can support healthy brain function, boost mental clarity, and reduce stress-related brain fog.

This Stress Awareness Week, we’re exploring how stress affects the brain - and sharing practical nutritionist-approved tips to help you stay clear-headed, resilient, and mentally supported during challenging times.

The Science: How Stress Affects the Brain

Many women describe stress as “a heavy mental load” - worrying about family, work, health, and all the invisible responsibilities in between. But stress doesn’t just feel overwhelming - it changes how the brain works.

When we experience stress, the body releases cortisol, our primary stress hormone. Cortisol is helpful in short bursts - it sharpens reactions and helps us cope in moments of challenge. But when stress becomes chronic, cortisol remains elevated, and this is where problems begin, particularly with brain function.

Over time, continuously high cortisol levels can:

• Disrupt communication between brain cells
• Reduce activity in the prefrontal cortex, the region that supports planning, focus, and emotional regulation
• Shrink the hippocampus, the part of the brain responsible for memory and learning
• Increase inflammation, which further affects clarity and mood

This leads to the familiar symptoms many of us know too well:
Brain fog, forgetfulness, slow thinking, irritability, and mental fatigue.

This link between stress and brain fog is well-documented - and it explains why even simple tasks feel harder when life becomes overwhelming. The brain is functioning under pressure.

The encouraging news? The brain is resilient.
With the right inputs - food, movement, sleep, and targeted nutrients - healthy brain function can be restored and protected.

Nutritionist Tips to Reduce Stress-Related Brain Fog & Support Mental Wellbeing

Below, Efamol Nutritionist Victoria Malcolm shares practical, supportive ways to care for your mind - each grounded in both nutrition science and emotional wellbeing.

1. Move for Your Mind

Exercise is one of the most powerful natural stress relievers. It helps balance cortisol, boosts serotonin (the “feel-good” neurotransmitter), and improves sleep quality.

“Try to get outside every day - even a 20-minute brisk walk in the morning can help regulate your nervous system and circadian rhythm. Natural light exposure early in the day supports better mood and sleep later on.”

- Victoria Malcolm, Efamol Nutritionist

Regular movement also supports brain structure.

Research shows that regular exercise can actually increase the size of the hippocampus, improving memory and cognitive resilience - a major benefit if stress is clouding your thinking.

2. Prioritise Protein and Tryptophan

Tryptophan is an essential amino acid and the building block of serotonin, which influences mood, sleep, and emotional balance.

Good sources include:

• Turkey and chicken
• Eggs and fish
• Nuts and seeds
• Brown rice, oats, bananas

Pairing tryptophan-rich foods with complex carbohydrates helps it cross the blood-brain barrier more effectively - making it easier for your body to convert it into serotonin. This supports mental clarity, calmness and emotional stability - especially during periods of stress.

3. Support Your Nervous System With Key Nutrients

Stress increases the body’s demand for vitamins and minerals, particularly magnesium and B vitamins (B6 and B12) - nutrients that are essential for our nervous system function and energy levels.

Aim to include:

• Leafy greens (spinach, kale, chard)
• Nuts & seeds
• Whole grains

Magnesium helps relax both muscles and the nervous system, while B vitamins support stable energy levels and resilience to stress - reducing fatigue and helping the brain think more clearly.

4. Prioritise Restorative Sleep

Sleep is when the brain restores, resets and repairs. Too little sleep can intensify stress and significantly worsen brain fog.

Support deeper, more restorative sleep by:

• Dimming lights in the evening
• Avoiding screens 1–2 hours before bed
• Stretching or gentle yoga
• Keeping a consistent sleep schedule

Deep sleep allows the brain to clear metabolic waste and improves memory, mood, and concentration.

5. Prioritise Your Brain Health

The omega-3 fatty acid DHA is one of the most important structural fats in the brain, vital for the brain to function properly. It is found in oily fish, such as salmon, mackerel and sardines. 

"I recommend aiming for 1-2 portions of oily fish per week - this is the amount recommended by the NHS. If you struggle to include enough omega-3 in your diet, a quality omega-3 supplement such as Efamol Active Memory can help."

- Victoria Malcolm, Efamol Nutritionist

Efamol Active Memory contains a researched blend of omega-3 DHA, B vitamins, and Ginkgo Biloba - supporting memory, focus, and resilience to mental fatigue.

It’s a gentle, targeted way to support the brain during busy or stressful periods - especially for women who feel mentally “full” or foggy.

Final Thought

Stress is a part of life - but living with brain fog, forgetfulness, and mental fatigue doesn’t have to be. Small daily habits, nourishing foods, restorative rest, and supportive nutrients can help bring your brain back into balance.

This Stress Awareness Week, be kind to your mind.