Dementia rates are on the decline in Europe and the US thanks to a shift towards healthier lifestyles, new research claims.

According to a study of more than 60,000 people conducted by Harvard School of Public Health, the chance of developing dementia have fallen by 15 per cent every decade for the last 30 years.

Researchers conducting the study, which was presented at the Alzheimer’s Research UK conference in Harrogate, England on Wednesday, explained that the decline could be down to falling rates of smokers, with figures dropping to an all-time low in England in 2017.

Lead author Albert Hofman, chairman of the department of epidemiology at the Harvard School of Public Health, said: “Looking over three decades, the incidence rate of dementia in Europe and North America seems to be declining by around 15 per cent per decade.

“This finding is more pronounced in men than women and is likely to be driven by changes in cardiovascular risk factors and lifestyle.

Portraits of people living with dementia around the world Show all 8 1 /8 Portraits of people living with dementia around the world Portraits of people living with dementia around the world South Africa Heidedel Community Centre - A community centre dedicated to taking care of people displaced by mental illnesses and disabilities. It mostly houses people living with dementia. Many traditional healers tell family members that if they have dementia or other disorders they are cursed. These people do not have family to care for them, and this centre is one of the first centres that is privately funded in a township with limited government support Leah Beach Portraits of people living with dementia around the world Guatemala This is a family from Antigua in Guatemala. After undergoing surgery the father lost his ability to walk and also had amnesia, which developed into dementia. His wife who is a full time teacher had to make sacrifices to care for him. The daughter also left her job to care for him full time, while the mother works. They all adore him and would do anything and sacrifice anything for him Leah Beach Portraits of people living with dementia around the world South Africa Heidedel Community Centre - A community centre dedicated to taking care of people displaced by mental illnesses and disabilities. It mostly houses people living with dementia. Many traditional healers tell family members that if they have dementia or other disorders they are cursed. These people do not have family to care for them, and this centre is one of the first centres that is privately funded in a township with limited government support Leah Beach Portraits of people living with dementia around the world Guatemala ERMITA is an adult day-care centre located in the heart of Guatemala City. It is a privately funded organization that allows families to not only drop off loved ones for physical therapy and alternative therapeutic treatment methods, but also offers medications at a huge discount, and training classes for care partners. They have even established a dementia carers programme at the local university, as well as providing outreach in local homes Leah Beach Portraits of people living with dementia around the world South Africa Heidedel Community Centre - A community centre dedicated to taking care of people displaced by mental illnesses and disabilities. It mostly houses people living with dementia. Many traditional healers tell family members that if they have dementia or other disorders they are cursed. These people do not have family to care for them, and this centre is one of the first centres that is privately funded in a township with limited government support Leah Beach Portraits of people living with dementia around the world South Africa This woman is cared for by her son. The photograph captures the moment he brought out a pot that she had left on the stove which caught fire. As you can see in the photos she’s so embarrassed. He says he worries to leave her on her own and is so sad to see her lose her independence Leah Beach Portraits of people living with dementia around the world India This woman is a member of the Parsi community, a cultural group in India which has Persian ties. People with Persian heritage are considered to be a ‘race’ in India and there are often separate hospitals and community centres. This woman, who asked to remain anonymous, is an inhouse ‘patient’ in the ‘Parsi ward’ of a public hospital. She is living with dementia and her family hardly ever come to visit her. Most patients living in this ward are abandoned by their family, or have no family to look after them Leah Beach Portraits of people living with dementia around the world India Mrs Roop Chungani, 72 years old. Mrs Roop was a hairstylist in her youth and was known to be one of the most famous hairstylists in Mumbai, working with celebrities and high-profile stars of Bollywood. She worked in one of Bombay’s most famous beauty parlours. After her dementia diagnosis, she says that her husband was very hard on her because of the change in her behaviour Leah Beach

“We know that recent decades have seen a radical decline in smoking rates for men. While many people may have been persuaded to stop smoking due to an increased risk of cancer or heart disease, it is also a key risk factor for dementia.”

According to government figures, the number of smokers in England in 2017 stood at roughly 6.1 million, which is 1.6 million fewer than in 2011.

Hofman added that the decline may not continue, though, due to other factors that increase the risk of dementia, such as obesity and diabetes, being on the rise.

Dementia is a condition that affects the brain and is most common in people over the age of 65.

According to the NHS, it’s a syndrome associated with an ongoing decline of brain functioning that may lead to memory loss, reduced movement and difficulty carrying out daily activities.

Commenting on the research, Dr Carol Routledge, director at the charity Alzheimer’s Research UK, said: “While there is no drug to yet slow or stop diseases like Alzheimer’s, there is robust evidence that what’s good for the heart is also good for the brain.

"As well as maintaining a healthy blood pressure, the best current evidence suggests that not smoking, only drinking within the recommended limits, staying mentally and physically active, eating a balanced diet and keeping cholesterol levels in check can all help to keep our brains healthy as we age.”

While the preliminary findings from the study were presented at the conference, the full report is set to be published later this year.