Normal ageing vs dementia

We explain the difference between normal ageing and dementia, including examples of potential symptoms for three common types of dementia - Alzheimer's disease, vascular dementia and mixed dementia.

How is dementia different from normal ageing?

Many of us get a little more forgetful as we get older. Most people will need a bit longer to remember things, get distracted more easily or struggle to multi-task as well as they once did. This may become noticeable particularly from middle age - usually taken as during our 40s, 50s and early 60s - onwards.

These changes are normal, but they can be a nuisance and at times frustrating. However, you may worry that these things are an early sign of dementia. It's important not to worry too much about this. For most people, these changes will be the result of normal ageing and won't be down to dementia.

What is dementia and what are the symptoms?

Dementia is the term for a group of symptoms that occur when the brain is damaged by diseases. This includes Alzheimer's disease or diseases of the blood vessels that can cause a stroke. These diseases can cause a significant decline in a person's mental abilities or 'cognitive function' - our capacity for things like memory, thinking and reasoning.

For a doctor to diagnose dementia, a person's symptoms must have become bad enough to significantly affect their daily life, not just be an occasional minor irritation. This means having new problems with everyday activities about the house, in the community or at work. For example, starting to have problems paying household bills, using the phone, managing medicines, driving safely or meeting up with friends.

If a person has symptoms that are worse than would normally be expected for a healthy person their age, but are not severe enough to significantly affect their daily life, a doctor may diagnose mild cognitive impairment (MCI). This is not a type of dementia, though some people who have MCI will go on to develop dementia.

The signs of normal ageing and dementia

The table below lists some of the possible changes due to both normal ageing and early dementia. However, it is important to remember that everyone is different and not everyone with dementia will have all of these changes.

Other conditions may also account for some of them. For example, a person with depression can have problems making decisions, get confused easily and appear withdrawn or irritable.

Comparing the signs

The table shows changes for the most common types of dementia: Alzheimer's disease, vascular dementia and mixed dementia (which is usually a combination of both of these). Less common types of dementia may lead to early changes that are not shown in the table. These changes could be visual hallucinations (seeing things that are not really there) or very disturbed sleep, in dementia with Lewy bodies. Or they could be early changes in personality or behaviour, in frontotemporal dementia.

Don't use the table to try to 'spot' dementia in yourself or someone else. If after reading it you are worried about yourself or someone close to you, visit the GP and talk about your concerns. Dementia can only be diagnosed by a qualified and experienced health professional.

Ability Possible changes due to normal ageing Possible changes due to dementia

'Short-term' memory and learning new information

Sometimes forgetting people's names or appointments, but remembering them later

Forgetting the names of close friends or family, or forgetting recent events - for example, visitors you had that day

Occasionally forgetting something you were told

Asking for the same information over and over - for example, 'where are my keys?'

Misplacing things from time to time - for example, your mobile phone, glasses or the TV remote - but retracing steps to find them

Putting objects in unusual places - for example, putting your house keys in the bathroom cabinet

Planning, problem-solving and decision-making

Being a bit slower to react or think things through

Getting very confused when planning or thinking things through

Getting less able to juggle multiple tasks, especially when distracted

Having a lot of difficulty concentrating

Making a bad decision once in a while

Frequently poor judgement when dealing with money or when assessing risks

Occasionally making a mistake when doing family finances

Having trouble keeping track of monthly bills


Having a bit of trouble finding the right word sometimes

Having frequent problems finding the right word or frequently referring to objects as 'that thing' 

Needing to concentrate harder to keep up with a conversation

Having trouble following or joining a conversation

Losing the thread if distracted or many people speaking at once

Regularly losing the thread of what someone is saying


Getting confused about the day or the week but figuring it out later

Losing track of the date, season and the passage of time

Going into a room and forgetting why you went there, but remembering again quite quickly

Getting lost or not knowing where you are in a familiar place

Visual perceptual skills

Vision changes related to cataracts or other changes in the eyes, such as misty or cloudy vision

Problems interpreting visual information. For example, having difficulty judging distances on stairs, or misinterpreting patterns, such as a carpet, or reflections

Mood and behaviour

Sometimes being weary of work, family and social obligations

Becoming withdrawn and losing interest in work, socialising or hobbies

Sometimes feeling a bit low or anxious

Getting unusually sad, anxious, frightened or low in self-confidence

Developing specific ways of doing things and becoming irritable when a routine is disrupted

Becoming irritable or easily upset at home, at work, with friends or in places comfortable or familiar places

Worried about your memory?

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