Dementia strikes one in 14 people in the UK over 65, and 47 million people worldwide. Yet scientists are still urgently trying to find why the disease affects some but not others.

In the below infographic, Imperial researcher Dr Ruth Peters explores the latest research into the risk factors for dementia.

Inforgraphic displaying the risk factors for dementia

Text-only version

Risk factors for dementia: dementia expert Dr Ruth Peters from Imperial College London explores the latest research. 

These may increase risk

  • Excess alcohol: regular drinking above the NHS recommended levels increases your risk. Advice: drink within current recommended guidelines.
  • Poor diet: unhealthy eating habits can affect your risk of developing dementia. Advice: eat a balanced diet.
  • Smoking: smokers have a higher risk of developing dementia than non-smokers. Advice: stop smoking or don't start. 
  • Unhealthy weight: being overweight or obese is likely to increase your risk. However, the evidence is less clear in the over-65 age group. Advice: maintain a healthy weight. 
  • High blood pressure: high blood pressure increases your risk. Advice: take prescribed medication and maintain a healthy weight. 
  • High cholesterol: high cholesterol is associated with an increased risk of dementia. However, the evidence is less clear in the over-65 age group. Advice: follow a healthy diet and adhere to any treatment recommended by your GP. 
  • Diabetes: Type 2 diabetes is associated with increased risk of dementia. Advice: follow a healthy diet and maintain a healthy weight. Adhere to any treatment recommended by your GP.
  • Stroke: stroke causes damage within the brain and increases dementia risk. Advice: follow a healthy diet and maintain a healthy weight. Adhere to any treatment recommended by your GP.
  • Air pollution: air pollution increases risk of having a stroke and may increase risk of dementia. However, scientists say more evidence is needed. 

These may decrease risk

  • Physical activity: physical activity and exercise might help reduce risk of dementia. Advice: carry out a mixture of activities, as recommended by health professionals. 
  • Caffeine: some researchers think moderate amounts of caffeine may help protect against dementia.
  • Social engagement: some researchers think keeping contact with friends and joining in activities may help protect against dementia. However, scientists say we need more studies in this area. 
  • Brain training: brain training may hold benefits. It can help with daily tasks, such as remembering shopping lists, and may also reduce dementia risk.