People who are concerned about their memory have been encouraged to see a doctor.
Alison Cranage, spokeswoman for Alzheimer's Research UK, said that it is important to discuss matters with a doctor in order to determine the reason behind the memory loss.
It could be related to stress, depression or simply getting older, she explained.
Ms Cranage added: "Alzheimer's and other types of dementia are complex.
"It's becoming clear that they don't have one single cause. It is likely that a mixture of our age, genes, environment and lifestyle contribute to whether we develop dementia."
Earlier this month the Alzheimer's Society published a study suggesting that around half a million people will be living with the mental health condition by 2021 but without a diagnosis.
Ms Cranage advised people to take regular exercise, eat a healthy diet and keep an eye on their blood pressure to attempt to lower the chances of dementia.