Can’t think straight? Understanding brain fog and how to lift it
Written byLaura Harcourt
Reviewed byShaun Ward
From difficulty concentrating to feeling sluggish, brain fog is a feeling many of us recognise. But what causes it? We ask an expert how to get your thoughts back on track
Summary
1What does brain fog mean?
Brain fog is a non-medical term that’s often used to describe feeling sluggish, forgetful, unable to focus or think clearly.
2What can cause brain fog?
There are many things that can leave your brain in a fog, from being stressed out and anxious, not sleeping well or hormonal changes like menopause.
3How do you get rid of brain fog?
Focusing on your overall health and wellbeing, like managing stress and getting better sleep can be so beneficial for brain fog symptoms.
Finding it hard to focus, even after a full night’s sleep? If your thoughts are feeling slower or cloudy, you’re not alone. Many people experience this fuzzy-headed feeling, often called ‘brain fog’. While it’s not a medical diagnosis, it can make everyday tasks feel more difficult than they should. Our Senior Scientist, Shaun Ward, shares what may cause brain fog and the simple, practical steps that can help you feel clearer and more like yourself again.
What is brain fog?
Simply put, brain fog is a non-medical term used to describe feelings of mental sluggishness, forgetfulness, lack of focus or reduced clarity of thought.1,2 It’s not a formal medical diagnosis, but it’s a commonly reported symptom that can have a range of underlying causes.1
Shaun explains that, “brain fog is often described as a symptom reflecting underlying factors like sleep quality, mood, hormonal changes or nutritional status.”3
“Brain fog is a non-medical term used to describe feelings of mental sluggishness, forgetfulness, lack of focus or reduced clarity of thought”
What does brain fog feel like?
For some, brain fog can feel like they’re thinking through cotton wool, or like their thoughts are cloudy. For others, it can be forgetfulness or feeling slower than normal.2
Generally, brain fog symptoms can show up as:2,4
- difficulty concentrating
- forgetting words or appointments
- slower thinking
- feeling mentally “cloudy”
- struggling to multitask
However, Shaun says, “it’s important to remember that occasional lapses in focus are completely normal. Brain fog symptoms become more noticeable when they persist or start to interfere with day-to-day life like your performance at work, ability to make decisions or your relationships.”
What causes brain fog?
There isn’t one single cause of brain fog, instead, it’s often the result of a combination of factors. Here are six of the most common causes of brain fog:
- Not sleeping well
Ever had a restless night and then found yourself standing in the kitchen, staring at the kettle, unsure what you were about to make for breakfast? A good night’s sleep is important for many aspects of your health and wellness – Shaun tells us that “sleep plays a critical role in how your brain stores memories and how quickly it takes in and uses information. So, even a single night of poor rest can impair attention, reaction time and executive function – like planning and decision-making.”5,6 - Chronic stress
Too much stress can lead to an increase in your body’s main stress hormone, cortisol. Cortisol is an important hormone, but Shaun explains that “when it’s persistently elevated, it has been shown to affect your attention span, mental flexibility and working memory – which is your ability to hold and use information in the moment.”7 - Hormonal changes
Your hormones fluctuate over time, even over the course of the day. But some of these changes, like during perimenopause and menopause, have been linked with cognitive symptoms such as forgetfulness and difficulty concentrating.8 - Nutritional factors
There are some nutrients which are well-known to play important roles when it comes to brain health. “Nutrients like iron, iodine and DHA (an omega-3 fatty acid), work to help support our brain” Shaun says.9 Other key nutrients include zinc for normal cognitive function and to protect cells from oxidative stress, plus vitamin B12 and magnesium for normal psychological and nervous system function.9
“Eating a diet high in saturated fat and ultra-processed foods has been linked to increased inflammation,” says Shaun. “In some studies where people have been observed over time, more inflammation in the body has shown to negatively affect mental wellbeing and cognitive health.”10 Other nutritional factors, like dehydration, can also cause feelings of mental fatigue too.11 - Changes in blood sugar levels
Your blood sugar, also known as glucose, is the main sugar found in your bloodstream. It’s derived from food and acts as your body’s main energy source, but large swings in your blood glucose levels can affect your concentration and even your energy levels.12 - Being ill or taking medication
In some cases, brain fog can occur after you’ve been unwell, like after a viral infection, or as a side effect of certain medications.4,13 “If you feel persistently foggy or you’re experiencing severe cognitive symptoms, you should speak to your GP or a healthcare professional,” Shaun says. “They can then help you find out the cause and suggest appropriate treatment.”
Menopause brain fog
Menopause and brain fog can often go hand-in-hand –
in fact, some studies show that up to 62% of women report experiencing cognitive difficulties during perimenopause and the menopause, making it a really common symptom.14
Menopause brain fog is a term often used to describe symptoms like memory and attention difficulties that some women experience around the menopause transition.15
Many women report:1
- forgetting words mid-sentence
- walking into a room and forgetting why
- losing their train of thought
- feeling mentally slower or less focused
Shaun explains, “these symptoms often happen during menopause and perimenopause due to declining and fluctuating oestrogen levels which can affect neurotransmitters such as serotonin and acetylcholine, which are brain chemicals that help regulate memory and mood.”16
“Luckily, research suggests these symptoms are common and often temporary during the menopausal transition,” Shaun continues. “Importantly, menopause brain fog does not mean dementia –
for most women, cognitive function stabilises after the transition period.”15
How to get rid of brain fog
“There’s no one standout brain fog treatment,” Shaun explains. “Instead, for most people, supporting your overall health and wellbeing can help your brain feel clearer.” From getting better sleep to eating right, here are some ways to support your brain and clear feelings of fogginess:
- Prioritise sleep
Aiming for a consistent sleep pattern every night and making sure you get enough quality sleep (think between seven and nine hours) can help you feel more focused, improve your memory and help you think clearer.5 - Manage your stress
We all experience stress in our lives, and sometimes, managing that stress is easier said than done. Learning to manage your stress in a healthy way is key for keeping brain fog at bay. “Incorporating stress management techniques like mindfulness, doing some light exercise, spending time outside and practising breathwork can help regulate your stress responses,” Shaun explains.17,18,19 - Eat for steady energy
Instead of reaching for that high-sugar snack when the 3pm energy slump hits, try switching up your diet for more sustained energy throughout the day. Shaun tells us that “focusing on meals that include protein, fibre-rich wholegrains, colourful fruits and vegetables, healthy fats like olive oil or nuts and seeds are helpful for keeping you feeling more awake throughout the day.”12,20
“Relying on that quick sugary snack for an energy burst in the mid-afternoon can quickly lead to an energy crash,” Shaun explains. “Instead, making sure you eat balanced meals and stay hydrated, can help prevent an energy crash and the brain fog that can sometimes accompany it.”12 - Stay mentally active
“Engaging your brain by learning new skills, reading, interacting with people and doing regular exercise are all linked to keeping your brain resilient throughout your life,” says Shaun.21,22,23,24 So, instead of reaching for your phone or getting stuck in a doomscroll, why not read a book, do a puzzle or go for a walk - your brain will thank you. - Speak to your GP
If your symptoms persist or you have any concerns about your brain health, make sure to speak to your GP. They’ll be able to offer you tailored advice and further support like blood tests to measure key nutrients, if they feel it’s necessary.
FAQs
No, brain fog itself isn’t considered dangerous, but it can be a sign that something needs more TLC, whether that's stress, sleep or a nutrient deficiency.1,2 If your symptoms are persistent, worsening or affecting your daily life, it’s a good idea to speak to your GP to rule out any underlying causes.
How long brain fog lasts varies from person to person. For some, it’s short-term and linked to a specific trigger like a few nights of poor sleep, an illness or a stressful period.1 For others, it can linger for longer depending on the cause.
Yes, brain fog can be caused by anxiety. When you’re feeling anxious, your body is often in “fight or flight” mode, which can make it harder to focus, process information clearly or even remember things.7
The final say
We know that feeling foggy can be frustrating, especially when you can’t quite pinpoint why it’s happening. In many cases, it can be your body’s way of signalling that something needs a little extra attention –
whether that’s sleep, stress, hydration or a lack of nutrients. With the right support and a few lifestyle changes, that fuzzy, sluggish feeling doesn’t have to be your norm.
“Small, consistent changes can make a big difference,” Shaun emphasises. “Prioritising balanced meals, getting good sleep, managing stress and creating space for proper rest can all help you feel clearer and more focused over time. But if your symptoms persist or feel severe, it’s always best to speak to your GP.”
Looking for ways to combat stress and switch off at the end of a long day? Check out our easy stress management techniques or browse through our favourite relaxing products to help you relax, refresh and recharge.
Disclaimer:
This article provides informational advice and is not a substitute for medical care. Working with experts for accuracy, we take great care to ensure the information is up-to-date and relevant. However, you should always consult your GP or healthcare professional before using supplements or alternative products, particularly if you have medical conditions or are under supervision.
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