Expert outlines five differences between brain fog and Alzheimer’s disease
Alzheimer's Research UK adviser says transient forgetfulness differs from persistent memory loss; early diagnosis and GP review urged
A dementia expert has set out five behaviors that can help distinguish temporary "brain fog" from early stages of Alzheimer’s disease, stressing that persistent changes in memory or cognition merit medical review.
Emma Taylor, information services manager at Alzheimer’s Research UK, told The Sun that the principal distinction is duration and reversibility: brain fog is often temporary and linked to identifiable triggers, whereas Alzheimer’s-related decline tends to be progressive and persistent. She highlighted five everyday situations that people and clinicians can use to gauge whether forgetfulness is likely benign or a potential early sign of dementia.
Taylor said occasional lapses — walking into a room and briefly forgetting the reason, misplacing keys and then finding them, or struggling momentarily to find a word that later comes to mind — are more typical of brain fog. By contrast, she said, repeating such episodes routinely, putting important items in markedly inappropriate places and having no recollection of doing so, or using unrelated words for familiar objects can be warning signs that merit further assessment.
On appointments and conversations, Taylor distinguished temporary lapses from sustained impairment. Forgetting an appointment but recalling it after a prompt, or later remembering it unaided, aligns with brain fog, she said. If someone repeatedly forgets the same engagement even after reminders, or loses track of what people are saying and must have questions repeated often, that pattern may indicate Alzheimer’s disease.
Dr. Simon Wheeler, senior knowledge officer at the Alzheimer’s Society, told the same outlet that brain fog is not a disease but a symptom that can arise from many common conditions, including menopause, sleep disruption, chronic pain and chronic fatigue syndrome. He advised people who are worried about cognitive symptoms to consult diagnostic tools such as the Alzheimer’s Society symptom checklist and to see their general practitioner for evaluation.
Classic symptoms of dementia include difficulties with memory, slower thinking, impaired language and reduced judgment or mood changes. Researchers and clinicians have also reported less widely known early signs, including changes in sight, hearing, touch, balance and smell, and alterations in spatial awareness such as standing unusually close to others.
The distinction matters in clinical practice because an early diagnosis can enable treatments that address symptoms and, in some cases, slow progression. Alzheimer’s Research UK and the Alzheimer’s Society both advise that if someone is reluctant to seek help, family members can keep a diary of observed changes to share with clinicians and to guide conversations.
Dementia is a leading cause of death and disability in older populations. Alzheimer’s Research UK reported 74,261 deaths from dementia in the United Kingdom in 2022, up from 69,178 the previous year, and estimates that more than 944,000 people are living with dementia in the UK. Internationally, around seven million people in the United States are thought to live with the condition. Women account for a majority of dementia diagnoses in the UK; Alzheimer’s Research UK estimates about 62% of those diagnosed are female and links part of that disparity to hormonal changes associated with menopause and reductions in estrogen, which the organization says plays a role in protecting brain health.
The economic burden is substantial. Analysis by the Alzheimer’s Society estimated the annual cost of dementia in the UK at about £42 billion, including unpaid carer losses, and projected costs could rise to about £90 billion within 15 years as the population ages.
Taylor reiterated that many causes of brain fog are treatable or manageable with medical help and encouraged people to consult a GP if symptoms cause concern. Both Alzheimer’s Research UK and the Alzheimer’s Society provide resources and guidance for people worried about cognitive changes and for families navigating conversations about diagnosis and care.