Research has identified many risk factors associated with dementia. It's impossible to eliminate every single one; after all we can't avoid age, which is the most significant. However, there are things that could affect the risk of developing dementia that we may be able to change.
The factors below cover some of the things that affect brain health, in good or bad ways. They look at what the current evidence says in terms of how they may be related to the risk of developing dementia.
Keeping physically active is important for brain health as well as heart health, and should be adopted as part of a healthy lifestyle. Research shows that regular exercise in middle-aged or older adults can improve thinking and memory, and reduce the risk of developing dementia.
Try to be physically active for at least 30 minutes, five times a week, with a moderate-intensity activity such as brisk walking or cycling. You should be working hard enough to raise your heart rate and break a sweat.
High blood pressure in mid-life significantly increases the likelihood of developing dementia in later life. If you are over the age of 40 you should get your blood pressure checked regularly and follow medical advice to keep it under control.
There is a strong link between type 2 diabetes and the risk of developing dementia. There are things that you can do to reduce your risk of developing diabetes, such as staying at a healthy weight and eating a balanced diet that is low in sugar. If you already have diabetes, it's important to manage your condition well.
Smoking has an extremely harmful effect on the heart, lungs and blood vessels, including the blood vessels in the brain. Research shows that smokers have a 50 per cent greater chance of developing dementia than those who have never smoked, but this risk can be significantly reduced by quitting the habit.
If you want to stop smoking it is a good idea to visit your GP. They can provide help and advice about quitting, and can refer you to an NHS Stop Smoking Service. For more information about quitting, call the NHS Smoke Free Helpline on 0800 022 4332.
Diet can affect a person's risk of developing many types of illness, including dementia. A healthy balanced diet that enables a person to maintain a normal body weight is likely to reduce the chance of developing high blood pressure or heart disease, both of which put a person at greater risk of developing dementia.
Eating a Mediterranean-style diet – with a high proportion of oily fish, fruit, vegetables, unrefined cereals such as whole-grain bread and olive oil, and low levels of red meat and sweets - may help to reduce the risk of dementia.
Research suggests that people who take part in activities that stimulate the brain (such as reading, learning and doing puzzles) are less likely to develop dementia, compared with those who do not engage in these activities.
It is thought that mental activity increases the brain's ability to cope with, and compensate for, physical damage. This would mean a person who often takes part in these activities will be able to tolerate a greater level of damage before symptoms of dementia are detected. Taking up new hobbies or learning new skills are great ways to challenge your brain and keep it active.
People with depression are probably at a greater risk of developing dementia. If you are experiencing symptoms of depression, you should seek help from your GP early because it can be treated, either with drugs or talking therapies (or both).
Obesity increases someone's chances of developing risk factors for dementia, such as high blood pressure and diabetes. This means people who are obese, especially in mid-life, are at an increased risk of developing dementia.
Eating a healthy diet and exercising regularly will help people to avoid becoming obese and (in most cases) to lose weight.
Drinking more than the recommended levels of alcohol increases the risk of developing various forms of dementia, such as Alzheimer’s Disease and vascular dementia. However, research suggests that light-to-moderate amounts of alcohol may protect the brain against dementia and keep the heart and vascular system healthy.
NHS guidelines suggest that men should not regularly drink more than 3–4 units of alcohol a day, and women should not regularly drink more than 2–3 units a day. A pint of lower-strength lager and a standard 175ml glass of wine each contain around two units of alcohol.
Evidence shows that high cholesterol levels in mid-life can increase your risk of dementia later on. Cholesterol levels later in life do not seem to have the same effect.
People over the age of 40 should get their cholesterol levels checked to make sure they are within a healthy range. If your blood cholesterol is too high, your GP can give you advice on how to bring it down.