What is Brain Fog?
“Brain fog” isn’t a medical diagnosis, but it is a widely recognised experience. It includes a broad set of symptoms that may impact cognition[1]. People often describe it as feeling mentally cloudy, slow or forgetful. This means people may struggling to concentrate, recall words or stay focused on tasks. These cognitive symptoms may occur during perimenopause or menopause and are frequently reported during the late 30s, 40s and early 50s.
What are the Symptoms of Brain Fog?
According to research, brain fog can include[2]:
- Difficulty concentrating or multitasking
- Forgetfulness
- Difficulty making decisions
- Reduced mental stamina
- Feeling overwhelmed
While stress, workload and lifestyle all play a role, many people notice that hormone brain fog feels different, with it more persistent and less responsive to rest alone.
Why Brain Fog Spikes in Perimenopause
Oestrogen plays a vital role in brain health. It helps stimulate brain activity, supports the growth and connection of brain cells, and contributes to healthy nerve signalling[3]. Oestrogen also influences key neurotransmitters involved in memory, mood and attention, which is why changes in levels can affect mental clarity and focus.
Testosterone, which is also produced by the ovaries, supports cognitive sharpness, motivation and energy levels. In the brain, it helps strengthen nerve pathways and supports healthy blood flow by maintaining the arteries that supply oxygen and nutrients to brain tissue – both important for memory and overall cognitive performance.
During perimenopause, levels of oestrogen and testosterone often fluctuate rather than decline steadily. These hormonal ups and downs can leave the brain temporarily under-supported, contributing to forgetfulness, difficulty concentrating and the familiar experience of “brain fog”.
These hormonal shifts help explain why menopause brain fog can appear suddenly and inconsistently. According to the NHS, cognitive and psychological changes including forgetfulness and difficulty concentrating are common during this transition, with brain fog increasingly recognised as part of the menopausal experience[4].
Importantly, for most women, brain fog and cognitive changes around menopause are subtle and often improve with time and support.
To learn more about why brain fog occurs during menopause, as well as natural remedies to support brain clarity, read our blog here.
Sleep Disruption and Cognitive Performance
Sleep quality is a key foundation for mental clarity, focus and emotional balance. During perimenopause, hormonal fluctuations can disrupt sleep patterns, often showing up as night sweats, increased anxiety or shifts in circadian rhythm.
The NHS advises that most adults need between 7 and 9 hours of sleep each night to support optimal brain function[5]. Even short periods of disrupted or insufficient sleep can interfere with attention, memory consolidation and emotional regulation, which may make brain fog more noticeable.
Research has also identified a link between fragmented sleep and reduced working memory[6]. For this reason, supporting healthy sleep patterns is considered a vital step in managing cognitive symptoms like brain fog.
Nutritional Support
Nutrition provides the building blocks for brain health and energy production. While supplements are not a cure, targeted support may be helpful.
Key nutrients to consider:
1. B Vitamins
B vitamins are a group of essential nutrients that play an important role in psychological function, nervous system health and energy metabolism. Vitamins such as B6, B12 and folate contribute to normal cognitive processes by supporting neurotransmitter synthesis and helping the body convert food into usable energy. Together, these functions support mental clarity and everyday cognitive performance.
2. Magnesium
Magnesium is an essential mineral involved in hundreds of processes throughout the body, including energy metabolism, nerve signalling and muscle function. It plays an important role in supporting relaxation and normal sleep patterns, making it particularly relevant for maintaining balance within the nervous system and overall wellbeing.
To learn more about how magnesium supports the body, you can explore our guide on daily magnesium needs, as well as our blog discussing its role in sleep support and guidance on when to take it.
3. Omega-3 Fatty Acids
Omega-3 fatty acids are essential fats found primarily in oily fish. One of the most important omega-3s for brain health is DHA (docosahexaenoic acid), which is a key structural component of brain tissue and brain cell membranes. This structural role is important for maintaining normal communication between brain cells and supporting overall cognitive function.
Diets that provide adequate omega-3 intake are commonly associated with the maintenance of brain health across different stages of life.
To learn more about omega-3s, you can read our dedicated blog exploring their role in overall health.
Herbal Support
Herbal remedies have traditionally played a role in supporting both brain and hormone health, recognising the close connection between mood, stress response and hormonal rhythms. During periods of hormonal transition, such as perimenopause or menopause, gentle botanical support is often explored as part of a broader approach to wellbeing.
Note: Before considering any herbal remedies, we recommend speaking to a registered herbalist first. Napiers has been trusted for over 165 years, supporting generations with their health, naturally. Book a free 1:1 consultation with one of our herbalists, and we can recommend a collection of herbs tailored to your individual needs.
Adaptogenic herbs such as ashwagandha are traditionally used to help the body adapt to physical and emotional stress. Adaptogens work by supporting the body’s stress response systems, which may be particularly relevant during perimenopause, when fluctuating hormones can place additional strain on the nervous system. You can learn more about adaptogens and their role in stress resilience in our dedicated blog.
Some women also explored herbs that support balance under practitioner guidance during brain fog perimenopause. Herbs such as sage have a long history of traditional use for supporting menopausal comfort, while black cohosh has been studied for its potential role in easing menopausal symptoms. These herbs are not suitable for everyone and are typically recommended only after an individual assessment.
To explore more on black cohosh and how it can provide support during menopause, read our blog here.
Herbs such as wild yam are often incorporated into holistic wellbeing practices during life-stage transitions. Wild yam has a long history of traditional use and is commonly associated with supporting balance and everyday comfort. Much of its popularity is linked to diosgenin, a naturally occurring compound found in the root. Diosgenin is frequently discussed in wellness traditions for its similarity in structure to certain hormones, which has led to interest in its role within broader hormonal-support. Historically, wild yam has also been valued for promoting stamina and overall vitality. Read more in our guide to wild yam.
Herbs should be viewed as supportive tools rather than quick fixes, and suitability varies between individuals. The right herbs, used at the right time and in the right form, may offer gentle support alongside nutrition, lifestyle changes and stress management strategies.
Supplements, such as COQ10 ubiquinol, are also commonly used to support cellular energy and brain function. Certain nutrients play a role in supporting mitochondrial activity, which underpins cellular energy generation. This additional support may have a positive knock-on effect for cognitive function, focus and overall balance within the body. Learn more about the benefits of CoQ10 here.
Lifestyle interventions that actually help
Simple lifestyle changes can make a meaningful difference to brain health and mental clarity:
- Strength training – activities such as resistance exercises or lifting weights help support steady energy levels and overall brain health.
- Stress management – gentle practices like mindfulness, slow breathing and spending time outdoors can help calm the nervous system and reduce overwhelming feelings.
- Sleep hygiene – keeping regular bedtimes, limiting screen use in the evening and creating a cool, dark sleeping space can all support better quality sleep.
To learn more about why sleep matters and how to build a routine that supports rest and recovery, you can read our blog on sleep support.
These approaches work together with nutritional and herbal support to help strengthen mental resilience and support clearer thinking over time.
If you’re looking to support overall brain health, explore our blogs which delve into building brain wealth as well as 5 daily habits to support the brain long-term.
FAQs
How much sleep do adults need?
Most adults require 7–9 hours of quality sleep per night for optimal cognitive function and emotional regulation.
What herbs help support sleep?
Traditionally used herbs include valerian, passionflower and chamomile. Adaptogens such as ashwagandha may support stress-related sleep disruption.
Is menopause brain fog permanent?
No. For most women, cognitive symptoms of menopause are temporary and improve with time, sleep support and stress management.
Can diet improve brain fog during perimenopause?
A balanced diet rich in omega-3s, B vitamins, protein and whole foods can support brain health.
References
- Denno, P., Zhao, S., Husain, M. and Hampshire, A. (2025) ‘Defining brain fog across medical conditions’, Trends in Neurosciences, 48(5), pp. 330–348. Available at: Cell Press Journal.
-
Metcalf, C.A., Duffy, K.A., Page, C.E. and Novick, A.M. (2023) ‘Cognitive problems in perimenopause: A review of recent evidence, Current Psychiatry Reports, 25, pp. 501–511. Available at: Springer Nature
-
The Menopause Charity. (2022) Brain fog. Available at: The Menopause Charity.
-
NHS. (2022) Symptoms – Menopause. Available at: NHS.
- NHS. (n.d.) Sleep problems. Available at: NHS.
- Okuda, M., Noda, A., Mabuchi, S., Iwamoto, K., Banno, M., Miyata, S., Yasuma, F. and Ozaki, N. (2021) ‘Sleep fragmentation and working memory in healthy adults’, Sleep Science, 14(2), pp. 111–117. Available at: NCBI.
