What is dementia?

Our brains control everything we think, feel, say and do. They also store our memories for us.

There are diseases that stop a person’s brain from working properly. When a person has one of these diseases, they may have problems remembering, thinking and speaking. They might say or do things that seem strange to others, and find it harder to do everyday things. They may not seem like the person they used to be.

Doctors use the word dementia to describe these different problems.

Why does it happen?

Dementia is not something that just happens to everyone as they get older. It is caused by different diseases.

Most people with dementia have Alzheimer’s disease or vascular dementia but there are other types too

These diseases affect different parts of the brain, so they affect people in different ways.

At the moment we don’t know why one person may get one of these diseases while another person may not. Doctors and scientists are working hard to find out more about dementia.

How does dementia affect someone?

Most of us forget things from time to time, like where we left our keys. This does not mean we have dementia. Symptoms of dementia slowly get worse until they get in the way of daily life.

When people start to get dementia, you might see some of these things happen:


Forgetting recent events, names and faces.


Asking the same questions often in a short space of time.


Putting things in the wrong place.


Finding it hard to pay attention or make simple decisions.


Not being sure about the date or time of day.


Getting lost, mostly in places that are new.


Finding it hard to use the right words or understand other people’s words.


Changes in how someone feels, like becoming sad or easily upset, or losing interest in things.

As dementia gets worse, people may have trouble speaking clearly or telling you what they need or how they feel. They may find it hard to eat and drink, wash and dress themselves, and go to the toilet without help.

Who is affected by dementia?

Dementia is very common.

Every day, almost 600 people
in the UK develop dementia.

In the UK there are
more women
with dementia than men.

People over 65 are much more likely to get dementia, but it can affect younger people too.

Some people may be more likely to develop dementia than others, like those who have had a stroke, or who have:

  • diabetes
  • high blood pressure
  • high cholesterol
  • depression.

Is there a cure?

At the moment there is no cure for dementia. Once a person has dementia, they will have it for the rest of their life.

There are some medicines that can help for a while, by making day-to-day life a little easier. There may also be group activities people can take part in to help them live better with their symptoms. Your doctor can tell you more about these.

Unfortunately there are no medicines at the moment that can stop these diseases so people will continue to get worse over time.

Can I stop myself getting dementia?

There is no sure way to stop yourself getting dementia, but there are things you can do that may make it less likely that you will.


Eat a balanced diet with plenty of fruit and vegetables.


Keep using your brain – through activities or social groups you enjoy.


Don’t smoke.


Keep your weight healthy.


Stay active and try not to spend too long sitting down.


If you have diabetes, keep to your doctor’s advice.


Ask your doctor to check your heart health, including blood pressure and cholesterol, and follow their advice if they are too high.


Drink no more than 14 units of alcohol per week.

This information was updated in November 2020 and is due for review in November 2022


Here are some other useful contacts

Admiral Nurses offer people with dementia and their families practical advice, support and tips.

0800 888 6678

Alzheimer’s Society provides information, help and local support groups. A translation service is available.
0333 150 3456

Alzheimer Scotland offers support services, information and advice to people in Scotland.
0808 808 3000


Dementia Research Infoline

Want to know more about dementia? Keen to get involved in research projects?

Contact the Dementia Research Infoline,

9am-5pm, Monday to Friday

0300 111 5 111


Where to go for help

If you think someone you know may have dementia, encourage them to go to see their doctor.

The doctor will check what might be causing their problems. Sometimes, the person might be sent to a second doctor who can tell them if they have dementia. You can go with your relative or friend if they ask you to.

If the doctor says anything you’re not sure about, speak up and ask them to explain.

ARUK - Clinic - 030

Caring for someone with dementia

Looking after someone with dementia can change your life in many ways. There is help for everyone affected by dementia, including family members. It’s important to remember you’re not alone.

Your doctor may be able to help you find support in your area. You can also contact your local Social Services office to see what help they can give you.