Key takeaways
  • Brain fog is a significant symptom during perimenopause, often surpassing hot flushes
  • Brain fog in perimenopause includes memory and attention difficulties, but it's temporary and typically improves after menopause
  • Changing oestrogen levels and neurotransmitters play a role. Strategies for managing brain fog include dietary choices, nutritional supplements, herbs, exercise, rest, and stress management

The hallmark symptoms of perimenopause and menopause are hot flushes and night sweats. What’s less known and talked about are the mental and cognitive impacts of this time of life. In fact, some studies have shown that brain fog is the highest reported symptom of perimenopause – higher than hot flushes. In this article, I’ll share the signs and symptoms of brain fog and what to look for as well as some strategies you can implement to help you navigate this challenging transition.

First, let’s get clear about the terminology.

The perimenopausal journey

Perimenopause is the transitional phase leading to menopause. It’s when the levels of reproductive hormones in a woman’s body start to change and she can experience changes in her menstrual cycle. The perimenopausal phase can last for up to ten years and it’s during this time, a woman may also notice a change in her cognitive capabilities. 

Menopause refers to the final menstrual period and marks the end of a woman’s natural reproductive capacity. It’s defined as the point when a woman hasn’t had a period for 12 months. Typically, symptoms of brain fog are worse during perimenopause, and improve once menopause is reached.

Because perimenopausal hormonal changes can start in a woman’s early forties when she still has a regular cycle, she may not realise that the cognitive changes (including brain fog) she’s experiencing are due to perimenopause. This can lead to a lot of anxiety and misdiagnosis of what’s going on.

Recognising brain fog: signs and symptoms

Brain fog is a cluster of cognitive symptoms that most frequently manifest in memory and attention difficulties.  Symptoms of brain fog include:

  • Difficulty recalling words, names, stories and numbers
  • Difficulty maintaining a train of thought
  • Distractibility
  • Forgetting intentions (reasons for coming into a specific room)
  • Difficulty switching between tasks

The good news is that the experience of brain fog tends to be a temporary state and is often worse during the perimenopause years and better once a woman has reached menopause.

The science behind perimenopause and brain fog

What’s happening during perimenopause to affect brain health in this way? The answer largely is due to the changing and declining oestrogen levels. Oestrogen is often only thought of in terms of its effects on reproductive health, but the reality is we have oestrogen receptors all over our body, with a significant number of them in the brain. 

Oestrogen is heavily involved in brain energy metabolism and decreased oestrogen leads to decreased energy metabolism in the brain. 

Oestrogen is also neuroprotective. So the brain is coping with increased inflammation and reduced brain energy metabolism, along with other hormonal and neurotransmitter changes.

The neurotransmitter dopamine also plays a role. As a neurotransmitter, dopamine is involved in learning, cognition, attention and memory. Oestrogen increases dopamine synthesis and decreases its degradation. Less oestrogen, or fluctuating levels, will result in less dopamine. 

Other possible causes of brain fog

It’s important to rule out other possible diagnoses if you’re in midlife and have brain fog. Other possible causes include:

  • Insomnia (could be due to hot flushes)
  • Iron deficiency anaemia
  • Low thyroid function (hypothyroidism)
  • Chronic pain – affects the ability to think
  • Burnout

Evaluation and assessment of the above is critical so that symptoms of another condition aren’t mistakenly attributed to perimenopause.

Another thing to consider is the stage of life. Midlife can be a particularly challenging time for both men and women, so it’s possible that many of a woman’s cognitive symptoms could be due to life stressors and good stress management is the first thing to consider.

Functional medicine approach to perimenopausal brain fog

There is no single cure for perimenopausal brain fog, but there are several strategies you can employ to reduce it and lessen its impact on your life.

The role of diet

Of all the varying diets that exist today, the Mediterranean diet stands out as having the strongest body of evidence supporting its positive impact on various aspects of health. It’s an anti-inflammatory diet, meaning it can reduce the neural inflammation that is so common in perimenopause. A Mediterranean diet includes ample vegetables, fruit and three or more servings of fish per week.

Soy isoflavones - As part of a Mediterranean diet, include good quality organic soy products such as tofu and tempeh. Soy products can be very beneficial, due to the isoflavones that they contain. Isoflavones act as natural SERMS (Selective Estrogen Receptor Modulators) which act on the oestrogen receptors in the brain, helping to alleviate brain fog.

Nutritional support

The following nutrients can provide extra support and reduce brain fog:

  • Magnesium – high intake of magnesium can lead to healthy brain volume and improved cognition
  • Omega 3 fatty acids – these fatty acids are abundant in the cell membranes of brain cells and are vital for the maintenance of normal brain function

Herbal support

We have a range of herbs that have traditionally been used to support the menopause transition. They include the following and will depend on your individual presentation:


An exercise regimen of at least 150 minutes of moderate-intensity aerobic physical activity a week is recommended to maintain optimal cognitive health. Exercise becomes even more critical as we get older. There’s evidence that the effects of exercise are cumulative and that it’s never too late to start. Maintaining a healthy BMI and slowing mid-life weight gain is also beneficial. Physical activity improves sleep, is supportive of neuroplasticity and is neuroprotective. 


As well as making time for exercise, making time for rest is also important. Women at this time of life have so many demands on their time that it’s easy to live in a state of overwhelm. Consciously making time for restful activities such as yoga, meditation and time in nature is important to reduce stress and brain fog.

Brain fog is a real and sometimes distressing part of perimenopause. The good news is that it’s not linked to an increased risk of dementia and tends to decrease once menopause is reached. 

By implementing diet and lifestyle changes and using targeted herbal and nutritional supplementation, you can decrease the impact of brain fog on your life.

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Vicki van der Meer
Vicki offers exceptional, results-driven healthcare, expertly treating thyroid issues, menopause, stress, and gut health with extensive clinical experience.
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{ "datePublished": "Oct 13, 2023" }