Video report by ITV News Correspondent Rebecca Barry
Dame Barbara Windsor has died aged 83 and while she will be remembered for many things, her final years were dominated by raising the awareness of Alzheimer's - the cruel brain disease that affects 850,000 people in the UK.
Alzheimer's disease is responsible for between 50-75% of all dementia cases in the UK and is not yet fully understood.
The pain of seeing a loved one slowly lose their memory has been felt by many across the country, with one in 14 people over the age of 65 suffering from the illness in the UK.
There has been considerable effort in recent years by the government and scientific communities to better understand dementia and Alzheimer's, but the research is still on-going.
What is Alzheimer's disease?
According to the Alzheimer's society, Alzheimer's is a physical disease that affects the brain.
The brain is made up of billions of nerve cells that connect to each other. One of their many functions is helping us recall memories.
People with Alzheimer's lose these connections over time because proteins build up and form abnormal structures called 'plaques' and 'tangles' which damage the nerve cells.
Plaques and tangles begin appearing when normal proteins begin building up in the brain to an abnormal level.
The reason why the proteins start building up above their normal level is not yet understood.
Alzheimer's often affects the hippocampus, a part of the brain that is vital in forming new memories.
The brain also is full of special chemicals that help send signals between cells.
People with Alzheimer's have less of these chemical messengers and so their signals are not passed on as well.
Alzheimer's is a progressive disease, meaning it will gradually get worse over time as more and more parts of the brain are lost, making the symptoms worse.
What are the symptoms and what are the early signs of Alzheimer's?
The NHS says the symptoms of Alzheimer's can be broken into three stages, early, middle and late.
The earliest symptoms of Alzheimer's are:
Forgetting recent conversations or events
Forgetting the names of places and objects
Having trouble thinking of the right word
Asking the same question repeatedly
Showing poor judgment or finding it harder to make decisions
Becoming less flexible and more hesitant to try new things
The NHS also says there are often signs of mood changes, anxiety, agitation or periods of confusion.
Middle-stage symptoms include all of the above but worse.
They may also begin getting lost, start exhibiting impulsive behaviour, become delusional, have mood swings and suffer from hallucinations.
In the later stages of Alzheimer's disease, the symptoms become increasingly severe and distressing to those around them.
By this time, much of the person's memory will be gone, delusions and hallucinations will become more frequent and they will start to lose basic cognitive abilities like being able to chew and swallow.
People with late-stage Alzheimer's need round the clock care.
What causes Alzheimer's?
While scientists do not know what causes the unusual build-up of proteins in the brain that is Alzheimer's disease, they have figured out what makes someone more likely to develop it.
The biggest risk factor is age. It mainly affects people over the age of 65 and risk increases as people get older - one in six people over the age of 80 have dementia.
According to the Alzheimer's society, gender is also a big factor, there are twice as many women with Alzheimer's than men.
Scientists have also identified it can be passed down through genetic inheritance but this only makes up for a small number of total Alzheimer's cases.
A person's health also plays a factor as fit and healthy people are less likely to develop Alzheimer's.
People who suffer from diabetes, a previous stroke or heart problems, high blood pressure or obesity are more likely to develop Alzheimer's.
Depression has also been heavily linked to Alzheimer's and is often a symptom of the disease.
Are there any treatments for Alzheimer's?
There is no cure for Alzheimer's.
There are drugs available that can slow down the process of the disease and helps brain cells communicate with each other.
Other drugs can be prescribed to help tackle some of the mental health issues caused by the disease.
There are also various therapies available aimed at improving brain function and restoring lost memories that can greatly improve the happiness of a person with Alzheimer's.
Because Alzheimer's often affects elderly people their children are usually the ones who take a main role in caring for them and it can be incredibly distressing for all involved.
The NHS and a wide range of charities offer support both for the people with Alzheimer's and the people caring for them.
If you need help for someone with Alzheimer's then you can visit the Alzheimer's Society webite.
You can also call the National Dementia Helpline on 0300 222 11 22.