Can Dementia Be Prevented?

  • Dec 06, 2016
  • Medical Conditions

Young Man With Glasses Sitting On Couch And Taking Notes Studying

A report published in 2014 by Dementia UK showed that in 2013 there were 815,827 people living with dementia within the UK (approximately 1.3% of the total population), with 775,502 of these people being aged 65 years old or over. (1)

A study carried out over two decades by a group of universities (including the University of Cambridge) has estimated that the number of people living with dementia has dropped by almost 20% (2). 1990s’ studies have predicted that there would be around 250,000 new cases of dementia per year. This prediction was proven to be inaccurate and the actual number of new cases is in the region of 210,000 per year (2).

This has led many to question whether there are actions people can take to reduce the risk of developing the symptoms of dementia, including common types such as Alzheimer’s Disease. There is scientific evidence showing that our lifestyle choices could affect our risk of developing the disease and practicing a combination of healthy behaviours seems to work better than adopting one or two (3).


Mediterranean foods have widely been thought to be one of the healthier diets since they contain a lot of fruits and vegetables, alongside moderate amounts of fish and white meat, with most of the fat coming from olive oil but also from the seeds and nuts used in the diet (4).

Olive Oil

Mediterranean diet contains a good amount of olive oil. This contains polyphenols, naturally occurring compounds found also in vegetables, fruits and cereals. Studies have found that the long-term consumption of food rich in polyphenols could offer protection against:

  • Cancers
  • Cardiovascular diseases
  • Diabetes
  • Neurodegenerative diseases (5)

PLOS One scientific journal conducted an experiment to examine what effects olive oil polyphenols have on the cognitive performance on mice. They gave some mice an extract called oleuropein aglycone which is a polyphenol found in olive oil, and they found that the mice who had been given this extract had an improvement in their cognitive function as opposed to those who had not been given the extract (6).


Some fruits also contain these polyphenolic compounds, especially soft fruits such as blueberries and raspberries. A recent study found that older rats who had been given polyphenols commonly found in blackcurrants have demonstrated improvements in their short-term memory (7).

There is however a debate over using rats and mice as opposed to humans because the ageing process and its effects on memory are much faster for most animals than for humans. Therefore, further tests on humans are required to confirm these results(7).


According to the World Health Organisation (WHO), smokers are at a 45% higher risk of developing dementia as opposed to the people who have never smoked, and 14% of all worldwide Alzheimer cases could possibly be attributed to smoking (8).

Action on Smoking and Health (ASH), as part of Public Health England (PHE) reinforce this by claiming that there is strong evidence that smoking increases the risk of developing dementia (9). They state that smoking can lead to dementia by:

  • increasing the risk of cardiovascular disease, diabetes and stroke (all of which are underlying risk factors in regards to dementia)
  • speeding up the build-up of fatty substances, leading to the blood vessels being narrowed, which in turn can lead to a deprivation of oxygen to the heart and brain (another risk factor for dementia)


Certain aspects of an individual’s lifestyle such as their physical activity and fitness levels are other factors that can play a role in developing dementia.

PLOS One and researchers from Cardiff University conducted and published a report claiming that they have found five lifestyle aspects that encouraged a disease-free life (9). These are

  • Taking regular exercise
  • Not smoking
  • Not being overweight
  • A healthy diet
  • A low alcohol intake

The people who participated in their study and consistently followed four or all the above-mentioned behaviours, experienced a decline of 60% in dementia with exercise being the strongest mitigating factor.

NHS Choices recommends that, to stay healthy, adults need to be active daily and engage in two types of activities: at least 150 minutes of moderate aerobic activity (such as cycling or fast walking) per week, and strength exercises on two or more days a week (exercises that will work all the major muscles) (10).


There is no certain way to prevent all types of dementia but making a few changes to your lifestyle now could help you lower the risk of developing dementia when you are older and it could also help you prevent some other illnesses such as cardiovascular diseases (11).


1. Alzheimer’s Society: Demography. Available here
2. ITV News. Article on Dementia rates falling by 20%. Available here
3. Alzheimer's Society. Risk factors for Dementia. Available here
4. BBC Goodfood: Why are Mediterranean diets so healthy. Available here  
5. PubMed Center (PMC) Article on benefits of polyphenols in food and drink. Available here
6. Plos One. Investigation on mice into effects of olive oil polyphenols. Available here
7. Blackcurrant Foundation. Aging and Brain Function. Available here
8. Alzheimer’s Society: Smoking Increases the risk of dementia. Available here
9. Alzheimer's Society. Research findings article. Available here
10. NHS: Physical Activity Guidelines for Adults. Available here
11.  NHS Choices. Can dementia be prevented. Available here