If you have become more forgetful, lost your train of thought mid-sentence or found it harder to concentrate, it is understandable to worry. Many women in perimenopause and menopause start to fear something more serious is going on, especially if dementia runs in the family. The reassuring news is that brain fog is a very common hormone-related symptom, and for many women it improves significantly with the right treatment.

What is brain fog?

Brain fog is not a formal medical diagnosis, but it is a very real experience. It can feel as though your thinking is slower than usual, or that your brain is working harder for less result. You might struggle to find the right word, forget names, misplace everyday items, lose focus at work or walk into a room and forget why you went there. Reading, decision-making and multitasking can suddenly feel much harder than they used to.

If this sounds familiar, you are not imagining it and you are certainly not alone. In a Newson survey of almost 6,000 women, 90% said they were affected by brain fog. That makes it one of the most widely reported symptoms of perimenopause and menopause.

Why hormones affect your brain

Estradiol, progesterone and testosterone all support memory, focus, mental sharpness and communication between brain cells. When these hormone levels fluctuate and fall during perimenopause and menopause, many women notice changes in memory, concentration and clarity of thought.

This is a direct biological effect, not a consequence of stress or ageing. Too often, women are told the opposite – that forgetfulness is just what midlife looks like. It is not. Hormone changes can have a measurable effect on brain function and that means treatment can help.

How is brain fog different from dementia?

This is the question many women are too worried to ask and it deserves a clear answer. Brain fog and dementia can overlap in some ways as both can involve forgetfulness, difficulty finding words and reduced confidence in daily tasks. The differences are usually in the pattern.

Menopausal brain fog often fluctuates. It tends to be worse when you are tired, stressed or sleeping poorly, and it may come and go alongside other symptoms such as anxiety, night sweats or low mood. Most women remain very aware of these changes and find them frustrating rather than confusing.

Dementia is typically progressive. Symptoms worsen over time rather than fluctuating. There may also be more noticeable changes in personality, behaviour and social awareness.

There is no single test that neatly separates brain fog from dementia for every woman. What matters is looking at the full picture (including your age, your stage of perimenopause or menopause, your other symptoms, your medical history) and how things are changing over time.

What if dementia runs in your family?

We understand that family history can make any memory symptom feel more frightening. The average lifetime risk of developing dementia is around 10% to 12%, rising to approximately 15% to 25% in people related to someone with dementia. But this is only one part of the picture.

Future risk is also shaped by factors that can often be improved. These include blood pressure, cholesterol, cardiovascular health, weight, mood and sleep. That means there is a good deal within your own influence.

Evidence also suggests that the longer a woman lives with low hormone levels, the greater her future dementia risk may be. Women with premature ovarian insufficiency who do not take hormone treatment may be at higher risk. This is one reason why hormones matter beyond symptom control – they are part of protecting long-term brain health.

Can hormone treatment help?

For many women, yes. The right type and dose of hormone treatment, often including testosterone when appropriate, can improve brain fog and help you think more clearly. Many women also find that once their hormones are better supported, sleep improves, energy returns and motivation to exercise comes back, which all feed into better cognitive function.

If you are already on hormone treatment but are still struggling with brain fog, it may be that the dose, type or overall plan needs reviewing. This is not a sign of failure. Rather it shows the importance of a carefully considered individual care plan.

What to do next

If you are worried about memory changes, speak to a healthcare professional who understands hormones and brain health. Keep a symptom diary that includes sleep, mood and cognitive changes, not just the cognitive changes in isolation. That context can be really helpful. And trust yourself. If you feel different, there is a reason. Brain fog in perimenopause and menopause is common, real and treatable.