Diet and exercise can prevent dementia

Nearly half of all dementia cases could be prevented if people adopted healthier lifestyles and took action to lower their cholesterol, a study has revealed.

In Australia there are an estimated 421,000 people living with all forms of the condition, according to Dementia Australia.

Nearly half of all dementia cases could be prevented if people adopted healthier lifestyles and took action to lower their cholesterol, a study has revealed.

The review by the Lancet Commission has unveiled 14 controllable risk factors, including obesity and too much alcohol, that are behind hundreds of thousands of cases in the UK.

It reveals for the first time that having high cholesterol, which affects six out of 10 adults, increases the risk of getting dementia by 30 per cent, and is responsible for 7 per cent of all dementia cases.

Experts said middle-aged people could ward off dementia by taking statins or doing more exercise to reduce “bad” LDL cholesterol, a fatty substance that builds up in the blood.

The paper was written by a team of 27 global dementia experts, led by University College London. It identified two new factors that contribute to dementia: high cholesterol and untreated sight loss in old age.

These were added to a list of 12 known risk factors including depression, smoking and loneliness, which were identified by the Lancet Commission in 2020 as causing dementia.

Between them, these 14 modifiable or treatable risk factors are responsible for 45 per cent of ­dementia cases.

In Australia there are an estimated 421,000 people living with all forms of the condition, according to Dementia Australia.

The authors said their findings demonstrated that dementia did not simply “hit people in a random way”, and confirmed that ­individuals have a lot of power to determine their fate.

They also called for radical public health policies, such as smoking bans and restrictions on junk food, to help prevent dementia, finding it would save as much as £4bn a year in England alone by reducing dementia-related costs to the NHS and social care.

The lead author, Gill Livingston from University College London, said: “When I first became a doctor, and for some time after, we thought that dementia was just one of these things that hit you in a sort of relatively random way and there was nothing that you could do. And if you were going to get it, you were going to get it.

“But now we know that’s not true, that even if you have genes which predispose you towards it, these lifestyle changes increase the number of years in good health, and it takes longer for you to get it.

“There are a lot of things that you could individually do to reduce the chance of you getting dementia and increase the number of years that you have a healthy life. I think that’s a remarkable bonus that we didn’t know about.”

Professor Livingston said one of the easiest ways to prevent dementia was to exercise every day.

“Give yourself a chance. What you do will not only decrease the chance of dementia, it will increase the quality of your life now,” she said.

Several of the risk factors, including high blood pressure, cholesterol and obesity, are linked to poor diet. Research shows that the longer people are exposed to these risks, the greater the effect. Therefore action in middle age to lose weight or stop smoking can dramatically cut dementia risk.

Much of the impact of lifestyle on dementia is due to the influence of blood circulation, which is linked to diet and exercise, on brain health.

There is also a growing understanding of the importance of education in early life at building up a bigger “cognitive reserve” which helps delay dementia in older age.

The new Lancet Commission, presented at the Alzheimer’s Association International Conference, made 13 recommendations for governments and individuals to help prevent dementia.

These include making hearing aids available for all those with hearing loss and reducing harmful noise exposure, and trying to detect and treat high cholesterol from the age of 40.

Writing in The Lancet Healthy Longevity, researchers from UCL also called for public health policies including sugar taxes, measures to tackle air pollution and alcohol pricing.

Dr Naaheed Mukadam, from UCL, added: “People can make changes to their lifestyles to reduce their own risk of developing dementia, but we particularly need policy-based approaches that do not place the burden on individuals. While these interventions cost money, they more than pay for themselves over time by reducing later health and social care costs.”

The Times