Forgetfulness: what is normal, what causes it and when to get checked

Forgetfulness here means the everyday kind: a name that will not come, keys you cannot find. The Korean word for it, geonmangjeung, is used for everyday forgetting, while the standard Korean dictionary also gives it the medical sense of a memory disorder in which experiences or a period of time cannot be recalled (National Institute of Korean Language, n.d.). The World Health Organization’s ICD-11 has no diagnosis of everyday forgetfulness; it lists “age-associated cognitive decline” as a symptom code and mild neurocognitive disorder as a separate diagnosis (World Health Organization, 2026). This guide is about the everyday kind.

Forgetting comes in different forms. The psychologist Daniel Schacter counted fading over time, absent-minded lapses when attention was elsewhere, and blocking, when something you know will not come, as three types of forgetting among memory’s mistakes, and he saw such mistakes as by-products of a memory that otherwise works well (Schacter, 1999). The tip-of-the-tongue state is the feeling of being temporarily unable to retrieve something you know (Schwartz & Metcalfe, 2011). Occasionally misplacing things or forgetting to pay a bill is usually mild forgetfulness too (National Institute on Aging, 2023).

How common is it? Across 16 cohorts in 15 countries, about one in four of 39,387 cognitively unimpaired people over 60 (23.8% to 25.6%) felt their thinking had declined, but figures varied from 6.1% to 52.7% between studies (Röhr et al., 2020). A Korean analysis of the 2021 Community Health Survey found that 22.7% of men and 29.9% of women aged 40 or older reported subjective cognitive decline (weighted estimates; Lee & Seo, 2024). In a US government survey, 11.2% of adults aged 45 or older said their memory loss or confusion had become worse or more frequent over the past year, including 10.4% of those aged 45 to 54 (227,393 respondents; Taylor et al., 2018). Questions and definitions differ, so the figures cannot be compared directly.

mind.io has no memory or dementia test, and this guide is not a diagnosis. It sets out, from research and official sources, how memory changes with age, how forgetfulness differs from signs of dementia, common causes that are not dementia, what research says about “digital dementia”, what helps memory and what has weak evidence, and where to get checked.

With age, some abilities decline slowly and others hold steady. Abilities such as vocabulary are resilient and may even improve, while conceptual reasoning, memory and processing speed decline gradually; processing speed begins to decline in the third decade of life. Within memory, recalling without a cue, remembering where you learned something and remembering to do things later decline with age, while recognising something when given a cue and procedural memory, how to do things, stay the same. These changes are small and should not impair everyday functioning (Harada et al., 2013).

Tip-of-the-tongue moments became more frequent with age and took longer to resolve, but the share resolved was the same across age groups, and given enough time even the oldest participants resolved nearly all of them (a 4-week diary study of 30 people each aged 18 to 24, 60 to 74 and 80 to 92; Heine et al., 1999). The Alzheimer’s Association lists as typical age-related changes sometimes forgetting names or appointments but remembering them later, sometimes having trouble finding the right word, misplacing things from time to time and retracing steps to find them, and getting confused about the day of the week but figuring it out later (Alzheimer’s Association, n.d.).

Most of this does not get in the way of daily life. People with age-related memory changes occasionally forget things such as where they left their car keys, but their ability to do daily activities or to think is not impaired, and they usually remember, if later than is convenient (Freedman, 2025). Most adults over 65 will not develop dementia or mild cognitive impairment (Harada et al., 2013). That does not make dementia a normal part of ageing: forgetfulness can be a normal part of ageing, but dementia is not (National Institute on Aging, 2023).

Korea’s National Institute of Dementia explains the difference this way: everyday forgetting loses part of an event or experience, while dementia often loses the fact that it happened at all. In everyday forgetting, the missing part often comes back with a hint or with time, and other thinking abilities and daily life are unchanged. These differences alone cannot always tell the two apart, however (National Institute of Dementia, n.d.a). The Japanese government gives remembering that you had breakfast but not what you ate as an example of age-related forgetting, and describes dementia as forgetting the whole experience (Government of Japan Public Relations Office, 2025).

Some changes call for a check: memory loss that disrupts daily life, asking the same questions over and over, getting lost in places you used to know well, having trouble following recipes or directions, and becoming more confused about time, people and places (Alzheimer’s Association, n.d.; National Institute on Aging, 2023). Memory that keeps getting slightly worse, and accusing someone of stealing things you cannot find, are also signs (National Institute of Dementia, n.d.a), as is being told by people around you that you have not seemed yourself lately (Government of Japan Public Relations Office, 2025). Not all of these have to be present for it to be dementia, and dementia is possible without them, so if you are concerned, talk to a professional (National Institute of Dementia, n.d.a).

People who notice and worry about their own forgetting typically do not have early dementia (Freedman, 2025). But that alone settles nothing. People in the early stages of dementia often notice too (Government of Japan Public Relations Office, 2025), and in a meta-analysis only 42.8% of people with dementia and 38.2% of those with mild cognitive impairment reported memory complaints. In community settings, even people who agreed their memory had worsened had only about a 20% chance of dementia and a 30% chance of mild cognitive impairment (Mitchell, 2008). So changes that others notice matter as well as your own impression.

Subjective cognitive decline means feeling that your thinking has kept getting worse compared with before, while standard tests adjusted for age, sex and education show normal results. It is a research concept rather than a diagnosis, and it includes normal ageing (Jessen et al., 2014). Older people who felt their memory had worsened (28 studies of 29,723 people, 14,714 of them with memory complaints, average age 71.6) were about twice as likely to develop dementia as those who did not, but the actual rate of progression was about 2.33% a year, and 14.1% in studies that followed people for more than four years (Mitchell et al., 2014).

Mild cognitive impairment is a decline in memory, language, orientation and similar abilities large enough to show on objective tests, while the ability to carry out daily activities is preserved, so it is not dementia. In a 2023 Korean government survey, 28.42% of people aged 65 or older had mild cognitive impairment and 9.25% had dementia; it was a two-stage survey in which 11,673 people aged 60 or older took a cognitive screening test and 1,900 of them had diagnostic assessment, and the government says the rise in mild cognitive impairment from 22.25% in 2016 partly reflects finer diagnostic criteria and more early screening (Ministry of Health and Welfare, 2025). About 5% to 10% of people with mild cognitive impairment progress to dementia each year, most do not progress even after 10 years (41 cohorts; Mitchell & Shiri-Feshki, 2009), and about 18% return to normal (25 studies; Canevelli et al., 2016).

Memory problems have many common, treatable causes besides dementia. The US National Institute on Aging lists head injury, thyroid, kidney or liver problems, medication side effects, mental health conditions such as depression and anxiety, alcohol or drug misuse, sleep problems and low levels of nutrients such as vitamin B12 (National Institute on Aging, 2023). The NHS also names anxiety or depression, sleeping problems and stress as common, treatable causes (NHS, 2023a). Memory problems from negative emotions are usually temporary and improve as the stress and emotions fade (National Institute on Aging, 2023).

Sleep and stress have also been tested in experiments. In a meta-analysis of studies with a full night without sleep, missing sleep before learning reduced memory by a medium to large amount, and missing sleep after learning by a small to medium amount, although publication bias was likely and most studies had very low power (Newbury et al., 2021). An analysis of 61 sleep-restriction studies also found poorer attention and executive functioning, with only a small effect on long-term memory (Lowe et al., 2017). In the laboratory, stress shortly before or during the moment of learning or recalling generally impaired memory (113 studies, 6,216 people; Shields et al., 2017). Being preoccupied by worries, and so not paying attention, is part of the reason (Freedman, 2025).

Mood matters too. In the analysis of Korea’s 2021 Community Health Survey, the factor most strongly linked with subjective cognitive decline was depressive symptoms (Lee & Seo, 2024). A meta-analysis found moderate deficits in executive function, memory and attention in people with depression (Rock et al., 2014), and higher anxiety went with lower scores for working memory, the information you hold in mind for a moment (177 samples, 22,061 people; Moran, 2016). In a study of 125 young adults (average age 21), memory complaints were linked with depression rather than with actual test scores (Csábi et al., 2025). In older people, depression can look like dementia, which is called pseudodementia. People with it are usually aware of their memory loss and complain about it, rarely forget important events, and often have other symptoms such as intense sadness, sleeping problems or loss of appetite (Freedman, 2025; National Institute of Dementia, n.d.a). Yet across 15 follow-up studies about 38% later developed irreversible dementia while 48% did not (Brodaty & Connors, 2020), so it is worth having both mood and memory looked at.

Check your medicines too. Medicines with anticholinergic effects (including some antidepressants and many antihistamines used in sleep aids, cold remedies and allergy medicines), sedatives that help people sleep, opioids and alcohol can affect memory, and problems can follow a new medicine or a higher dose (Freedman, 2025). There is low-certainty evidence that older adults who take medicines with anticholinergic effects may be at increased risk of cognitive decline or dementia (25 studies, 968,428 people; Taylor-Rowan et al., 2021). People taking benzodiazepines showed poorer recent memory and working memory, among other things (19 studies; Crowe & Stranks, 2018), although benzodiazepines do not appear to cause dementia (Livingston et al., 2024). Do not stop a medicine on your own; talk to the doctor who prescribed it or a pharmacist.

Physical health and stage of life play a part as well. An underactive thyroid and vitamin B12 deficiency are reversible causes of memory loss that blood tests can detect (Freedman, 2025; NHS, 2023b). However, in a 2003 analysis of 39 studies, potentially reversible causes were found in 9% of people with dementia, and only 0.6% actually reversed, partly or fully (Clarfield, 2003). Around the menopause, people may have problems with memory or concentration, sometimes called brain fog, which can feel worse with poor sleep and tiredness (NHS, 2026). In a study following 2,362 US women for four years, learning performance that dipped during the menopause transition returned to its earlier level afterwards (Greendale et al., 2009). Long COVID can also bring memory and concentration problems (NHS, 2025a). If you have been easily distracted and forgetful and often lost things since childhood, it could be adult ADHD (NHS, 2025b). Poor eyesight or hearing loss can also make memory problems worse (Pour les personnes âgées, 2026).

“Digital dementia” is not a medical diagnosis. Korea’s Urimalsaem dictionary labels digital dementia (dijiteol chimae) a general social term for a state in which reliance on digital devices has greatly weakened memory or calculation, and the standard dictionary has no entry for it (National Institute of Korean Language, n.d.). Researchers have weighed the “digital dementia” hypothesis, that a lifetime of technology exposure worsens thinking, against a “technological reserve” hypothesis, that digital technology encourages behaviours that preserve cognition (Benge & Scullin, 2025).

The link between attention and memory has more support. In a study of 80 young adults (average age 21.7), moments when attention lapsed partly explained what they remembered or forgot, and heavier media multitasking went with a tendency to have attention lapses and forget (Madore et al., 2020). But a meta-analysis of 39 effect sizes found only a weak link between media multitasking and distractibility, which disappeared after correcting for small-study effects (Wiradhany & Nieuwenstein, 2017). An analysis of 22 studies on whether using a smartphone, or simply having one nearby, lowers performance found a small overall effect that was clear only for memory, with large differences between studies (Böttger et al., 2023). Museum visitors who photographed whole objects remembered fewer of them, but those who zoomed in on a detail did not remember less (Henkel, 2014).

Handing memory to devices has costs and benefits. In three experiments (172 people each), offloading to an external tool improved performance on the task but people remembered less of what they had offloaded. In one experiment the loss remained even when people knew a memory test was coming; in another, people who were made to offload as much as possible but knew about the test almost completely made up for it. The researchers stress having an explicit goal to remember when relying on tools (Grinschgl et al., 2021). Reminders are highly effective: in one experiment, people forgot about 45% of intended tasks when relying on their own memory but only about 5% with reminders. The authors consider fears of digital dementia overstated, because they assume long-term harm from short-term evidence (Gilbert et al., 2023).

Data on older adults point the other way. In a meta-analysis of 57 studies including 411,430 adults over 50, use of digital technology was associated with a lower risk of cognitive impairment and slower cognitive decline. But people with better thinking may simply use technology more, so causation still needs testing (Benge & Scullin, 2025). It makes sense to hand devices what they can hold, while deliberately setting out to remember what you really need to. If smartphone use itself is the problem, see smartphone overuse.

Some everyday methods can be used straight away: focusing on one thing at a time, making lists, keeping a calendar, establishing routines, linking a new person’s name to something you already know or repeating it several times, and keeping frequently used items in the same place (Freedman, 2025). Official advice also suggests putting your wallet or purse, keys, phone and glasses in the same place each day (National Institute on Aging, 2023). Plans that pair a situation with an action in advance, in the form “if this happens, then I will do that”, helped people remember to do things later in experiments (36 comparisons; Chen et al., 2015). In a trial of 40 people with mild cognitive impairment, those trained to use a calendar and notebook kept using them more and managed daily activities better than those who were only given them (Greenaway et al., 2013).

Sleep and exercise help too. People remembered more after sleep than after the same time awake (a meta-analysis of experiments reported in 177 articles; Berres & Erdfelder, 2021). The US National Institute on Aging advises getting enough sleep, generally seven to eight hours a night (National Institute on Aging, 2023). After cognitive behavioural therapy for insomnia, people’s own ratings of their thinking improved, but evidence for improvements on objective tests is still lacking (18 studies; Herbert et al., 2018). The World Health Organization strongly recommends physical activity for adults with normal cognition to reduce the risk of cognitive decline (moderate-quality evidence; World Health Organization, 2019). Still, the effect of exercise on adults’ memory is small (Singh et al., 2025), and a Cochrane review of aerobic exercise in healthy older people found no cognitive benefit (12 trials, 754 people; Young et al., 2015).

Look after mood, hearing, drinking and smoking. Depression needs treatment in its own right (World Health Organization, 2019), and older people should be offered hearing screening and hearing aids so that hearing loss is found and managed in time, although, as of these 2019 guidelines, the evidence that hearing aids lower the risk of cognitive decline or dementia was insufficient (World Health Organization, 2019). In a trial of 977 people aged 70 to 84 with untreated hearing loss, a hearing intervention did not reduce cognitive decline over three years overall, and decline was slower only in a group with more risk factors (Lin et al., 2023). Cutting down on harmful drinking and stopping smoking are also recommended to reduce the risk of cognitive decline (World Health Organization, 2019).

Some things have weak evidence. Brain-training games improve scores on the trained tasks, but there is little evidence that they improve everyday thinking (Simons et al., 2016). In a Cochrane review of healthy people aged 65 or older (8 trials, 1,183 people), computerised cognitive training may have had a slight effect at the end of training, but the evidence was low quality and there was no evidence that it lasted 12 months (Gates et al., 2020). The World Health Organization recommends against vitamins B and E, polyunsaturated fatty acids (such as omega-3) and multi-complex supplements to reduce the risk of cognitive decline or dementia (strong recommendation; World Health Organization, 2019). In 28 studies of healthy middle-aged and older people (more than 83,000 participants), no vitamin or mineral supplement showed a meaningful effect on cognitive decline (Rutjes et al., 2018), and in a trial that randomised 3,069 people aged 75 or older to ginkgo extract or placebo and followed them for a median of 6.1 years, ginkgo did not reduce dementia (DeKosky et al., 2008). Be cautious of pills, supplements and brain games that promise better memory; they may be unsafe, a waste of money, or both (National Institute on Aging, 2023).

Research on dementia prevention is worth knowing about. The 2024 Lancet Commission estimated that if 14 risk factors, including less education, hearing loss, high LDL cholesterol, depression, physical inactivity, smoking, excessive drinking, high blood pressure and diabetes, were all eliminated, about 45% of dementia could theoretically be prevented. This is a modelled estimate that assumes the risk factors are causes, and some links may be only partly causal (Livingston et al., 2024). It is better read as a direction for long-term brain health than as a fix for everyday forgetfulness.

Get checked if memory problems are affecting your day-to-day life (NHS, 2023a), seemed to come from stress or low mood but persist after a few weeks (National Institute on Aging, 2023) or keep getting slightly worse (National Institute of Dementia, n.d.a). Being worried about your memory is reason enough to see a doctor (NHS, 2023c). It helps to bring someone who can describe the problems with you, and do not try to self-diagnose the cause (NHS, 2023a). If memory problems come on suddenly together with a headache, seizures, facial paralysis or weakness in a limb, call emergency services straight away (Pour les personnes âgées, 2026).

In Korea, dementia relief centres at public health centres offer screening. Diagnosis proceeds through screening, diagnostic and differential tests, and if screening shows something abnormal, the diagnostic and differential tests are done at partner hospitals (National Institute of Dementia, n.d.b). Screening uses the Cognitive Impairment Screening Test (CIST), takes about 15 minutes as a one-to-one interview and is free (National Health Insurance Service, 2022; Gongju City Health Center, n.d.). It is usually for people aged 60 or older without a diagnosis of dementia or mild cognitive impairment, though some areas offer it to all residents without a diagnosis. Some centres ask people with a normal result to repeat the screening a year later, and costs of the diagnostic and differential tests are partly covered for people meeting conditions such as a household income at or below 120% of the standard median income, and the amounts vary by area (Gongju City Health Center, n.d.; Suwon City Health Center, n.d.). Because arrangements differ locally, check with your nearest centre first. Questions can be put to the dementia call centre on 1899-9988 (every day, 7 a.m. to 10 p.m.) (National Institute of Dementia, n.d.c).

In Korea’s national health check-up, people aged 66 or older fill in a cognitive impairment questionnaire (KDSQ-C) every two years and, depending on the result, are referred to neurology, psychiatry or a dementia relief centre (Ministry of Health and Welfare, 2026). If dementia is suspected, a specialist dementia clinic, usually run by psychiatry or neurology, can make a diagnosis (National Institute of Dementia, n.d.b). In Japan, people can turn to the community comprehensive support centre in every municipality, their regular doctor, a hospital’s memory outpatient clinic or a dementia medical centre (Ministry of Health, Labour and Welfare, n.d.). In the UK, start with a GP, who can refer you to a specialist or a memory clinic (NHS, 2023c). In France, the regular doctor (médecin traitant) is the first port of call, and there are about 600 accredited memory clinics (consultations mémoire) across the country (Pour les personnes âgées, 2026).

No single test diagnoses dementia. Screening tests cannot diagnose it but may show memory difficulties that need further investigation, and scores can be influenced by education. Blood tests may check thyroid function and vitamin B12 and folate levels (NHS, 2023d). mind.io has no memory or dementia test. If forgetfulness comes with low mood and trouble concentrating, you can look back over the past 2 weeks with the depression check-in (PHQ-9), but it looks at mood, not memory. For sleep problems, see insomnia: what helps; if you suspect depression, see depression symptoms; and for a first appointment, see Seeing a psychiatrist for the first time.

Q. I am in my 20s or 30s and very forgetful. Could it be dementia? A. Look at other reasons first. In young people, memory complaints were linked with depression and anxiety (Zapater-Fajarí et al., 2024), and one study found no link with actual test scores (Csábi et al., 2025). In experiments, a sleepless night or a stressful moment also lowered memory (Newbury et al., 2021; Shields et al., 2017). If you have been easily distracted and often lost things since childhood, look at adult ADHD symptoms too (NHS, 2025b).

Q. Does worsening forgetfulness turn into dementia? A. Mostly not. Older people who felt their memory had worsened were about twice as likely to develop dementia as those who did not, but the actual rate of progression was about 2.33% a year (Mitchell et al., 2014). If your memory keeps getting slightly worse, though, get checked (National Institute of Dementia, n.d.a).

Q. If I notice my own forgetting, does that mean it is not dementia? A. Usually, but that alone settles nothing (Freedman, 2025). People in the early stages of dementia often notice too (Government of Japan Public Relations Office, 2025), and only 42.8% of people with dementia reported memory complaints (Mitchell, 2008).

Q. What is pseudodementia? A. It is depression that looks like dementia (Freedman, 2025). It has been seen as largely reversible once the depression improves, but across 15 follow-up studies about 38% later developed dementia and 48% did not (Brodaty & Connors, 2020). So it is worth having mood and memory checked together.

Q. Is digital dementia real? A. It is not a diagnosis (National Institute of Korean Language, n.d.). In 57 studies of people over 50, use of digital technology was in fact linked with a lower risk of cognitive impairment, though causation is unclear (Benge & Scullin, 2025). Still, research shows that we remember less when our attention lapses (Madore et al., 2020).

Q. Do memory supplements or brain games help? A. The evidence is weak. The World Health Organization recommends against vitamins B and E, polyunsaturated fatty acids and multi-complex supplements for preventing cognitive decline (World Health Organization, 2019), and brain training raises scores on the trained tasks with little evidence of better everyday thinking (Simons et al., 2016). A vitamin B12 deficiency confirmed by tests is a different matter and is treated with a doctor (NHS, 2023b).

Q. Why does a word sit on the tip of my tongue and not come out? A. That is the tip-of-the-tongue state, a temporary inability to retrieve something you know (Schwartz & Metcalfe, 2011). It becomes more frequent with age and takes longer to resolve, but given enough time nearly all of these words come back (Heine et al., 1999).

Q. Can I take a memory or dementia test on mind.io? A. No. mind.io has no memory or dementia test. No single test diagnoses dementia (NHS, 2023d); in the UK, start with a GP (NHS, 2023c), and in Korea, people aged 60 or older can usually get a free screening at a dementia relief centre (National Institute of Dementia, n.d.b).

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