Almost anyone can reduce the risk of dementia, even if working in the family, living a healthy lifestyle.
A survey of nearly 200,000 people showed that risk fell by up to a third.
The team at Exeter University said the results were exciting, empowering, and showed that people are not doomed to dementia.
The findings were revealed at the Alzheimer's International Conference.
- Dementia: All you need to know about the greatest health challenge of our time
What is considered a healthy lifestyle?
Researchers gave people a healthy lifestyle based on a combination of exercise, diet, alcohol and smoking.
This is an example of a person who scored well:
- He does not smoke right now
- Cycles are normalized for two and a half hours a week
- Eats a balanced diet that includes more than three servings of fruit and vegetables a day, eating fish twice a week and rarely eating processed meat
- He drinks up to one liter of beer a day
- He smokes regularly
- Do not do regular exercise
- Eating a diet that includes less than three servings of fruit and vegetables a week and includes two or more servings of processed meat and red meat per week
- He drinks at least three beer mugs a day
How easy is it to be done?
Sue Taylor, 62, of Exeter has seen the impact of dementia on the family – mother and grandmother have had the disease.
She runs park exercises three times a week – even in winter – and has a 45-minute walk before work.
"It takes a lot of effort, you need to think about it and make her fit," she told me.
But she says she deserves, especially for her grandchildren.
"I just want to keep my brain as sharp as possible as long as possible." I do not want to miss grandparents, both physically and mentally, "she said.
How big is the difference in lifestyle?
The study traced 196,383 people at the age of 64 for about eight years.
It analyzes the DNA of humans to assess their genetic risk of developing the disease.
The study showed that there were 18 cases of dementia per 1,000 people if they were born with high-risk genes and then had an unhealthy lifestyle.
But it dropped to 11 per 1,000 people during the study if these high-risk people have a healthy lifestyle.
Does not that look like a big difference?
Figures may look small, but this is because your average 60s are relatively young in terms of dementia.
Researchers say that reducing the percentage of dementia by one third will have a profound effect on older groups where the disease is more common.
"That could amount to hundreds of thousands of people," said Dr. David Levelin.
Also, this type of research can not conclusively prove that lifestyle causes different risks of dementia. He just notes the patterns in the data.
The results, published in the journal of the American Medical Association, coincide with previous studies and advice from the World Health Organization.
Can I completely avoid dementia?
Unfortunately, you can live the life of a saint and still get the disease. Lifestyle just changes chances.
However, there are still no drugs to change the course of this disease.
Reducing chances is all that anyone can do.
Is that true for everyone?
The results may not apply to people with a very early onset of dementia, which begins when people are in their 40s and 50s, the researchers say.
But they believe that their results will apply to people in older age groups when dementia becomes more common.
Researchers argue that the study refers to dementia rather than specific forms of the disease, such as Alzheimer's or vascular dementia.
What is the main message?
"Even if you are worried about dementia, perhaps you have a family history yourself, what it shows us is that it does not matter," said Dr. David Lavlyn.
– You are still likely to reduce the risk of dementia if you go to a healthy lifestyle.
"It's really an empowerment.
Another researcher Dr Elizibeta Kuzma said that for the first time someone has shown that it can counteract the hereditary risk of dementia and the findings are "exciting".
What do the experts say?
Fiona Carragger, Alzheimer's Society, commented: "One person develops dementia every three minutes in the UK, knowing how to reduce the risk of dementia may not be more important.
– So, hit this salad bar, change cocktail cocktail and take your kit!
Dr. Carroll Rutledge of Alzheimer's Research UK said the findings were "important."
"This is another proof that there are things we can all do to reduce the risk of developing dementia, but research shows that only 34% of adults think this is possible.
"While we can not change the genes we inherit, this study shows that changing our way of life can still help build the chances in our favor."
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