According to a recent research from the University of Cambridge, one in three cases of Alzheimer’s disease worldwide is preventable.

The main risk factors for the disease are a lack of exercise, smoking, depression and poor education, it says.

Previous research from 2011 put the estimate at one in two cases, but this new study takes into account overlapping risk factors.

According to the study, published in The Lancet Neurology, the Cambridge team analyzed population-based data to work out the main seven risk factors for Alzheimer’s disease.

Alzheimer’s disease main risks are:

• Diabetes
• Mid-life hypertension
• Mid-life obesity
• Physical inactivity
• Depression
• Smoking
• Low educational attainment
  

  The main risk factors for Alzheimer’s disease are a lack of exercise, smoking, depression and poor education

The researchers worked out that a third of Alzheimer’s cases could be linked to lifestyle factors that could be modified, such as lack of exercise and smoking.

They then looked at how reducing these factors could affect the number of future Alzheimer’s cases.

They found that by reducing each risk factor by 10%, nearly nine million cases of the disease could be prevented by 2050.

Current estimates suggest that more than 106 million people worldwide will be living with Alzheimer’s by 2050 – more than three times the number affected in 2010.

Prof Carol Brayne, from the Institute of Public Health at the University of Cambridge, said: “Although there is no single way to treat dementia, we may be able to take steps to reduce our risk of developing dementia at older ages.

“We know what many of these factors are, and that they are often linked.

“Simply tackling physical inactivity, for example, will reduce levels of obesity, hypertension and diabetes, and prevent some people from developing dementia.

“As well as being healthier in old age in general, it’s a win-win situation.”

Of the seven risk factors, the largest proportion of cases of Alzheimer’s in the US, UK and the rest of Europe can be attributed to physical inactivity.

The study says about a third of the adult population in these countries are physically inactive.

Physical inactivity is also linked to increased risks of other health problems, such as cancers and cardiovascular diseases.