• Low educational attainment is considered a risk factor for dementia

• ‘Despite some inconsistency among cohort studies, there is quite convincing evidence from high-income countries that higher levels of education and occupational attainment are associated with a lower incidence of dementia.’ 

• ‘The strongest evidence for possible causal associations with dementia are those of low education in early life’. 
• ‘There is considerable potential for reduction in dementia incidence associated with global improvements in access to secondary and tertiary education.’ 
• ‘Overall there appears to be a protective effect of education against developing dementia later in life'

Early life events

• ‘Parental death in early life is associated with a higher risk of incident AD and dementia.’ 

Psychological & Psychosocial Factors

Depression

• Depression is a risk factor for dementia 

• ‘[…] depression may increase dementia risk’
• ‘While our analysis clarifies the strength of the association between depression and the subsequent onset of dementia, it still does not distinguish clearly between the two most plausible explanations for this association – that is, whether depression is a prodrome of dementia, or an independent causal risk factor.’

Anxiety disorders

• ‘There is currently too little evidence on the relationship between anxiety and incident dementia to conclude whether this may be an independent risk factor.’ 

Sleep disorders

• ‘Evidence suggests that the relationship between sleep disturbances and dementia may in fact be bidirectional. Impairment of the neural pathways involved in the sleep-wake cycle caused by dementia might result in sleep disorders; but the reverse is also possible, where sleep problems might also be a risk factor for cognitive decline.’ 

Social isolation

• Social isolation is considered a risk factor for dementia 

• Social connections as well as loneliness have been associated with a risk of developing dementia.

Physical (in)activity 

• ‘Studies show that people can reduce their risk of dementia by getting regular exercise’. 
• ‘Some compelling evidence suggests that dementia is associated with many risk factors, including […] physical activity’ 

• Underactivity is considered a modifiable risk factor for dementia. 

Diet/ Nutrition

• The risk of dementia can be reduced with a healthy diet. 

• ‘The evidence suggests a Mediterranean or Scandinavian diet might have value in preventing cognitive decline in people with intact cognition, particularly as one component of a healthy lifestyle, although how long the exposure has to be or during which ages is unclear.’ The consumption of additional additional vitamins, oils, or mixed dietary supplements as a means of preventing dementia is not recommended. 

• ‘There is currently insufficient evidence to confirm a relationship between the micro- and macronutrients described above (vitamin B6, vitamin B12, folate, vitamin C, vitamin E, flavonoids, omega-3, Mediterranean diet) and cognitive function.’ 

Tobacco use

• The risk of dementia can be reduced by not smoking. 
• ‘In short and longer latency incidence studies, smoking increases the risk for Alzheimer’s disease’
• Interventions for tobacco cessation should be offered to adults who use tobacco since they may reduce the risk of cognitive decline and dementia in addition to other health benefits.

• ‘There is persuasive evidence that the dementia risk for populations can be modified through reduction in tobacco use’. 
• ‘The strongest evidence for possible causal associations with dementia are those of […] smoking […] across the life course’. 

Alcohol consumption

• The risk of dementia can be reduced by avoiding a harmful consumption of alcohol.

Hypertension

• The risk of dementia can be reduced by maintaining a healthy blood pressure. 

• Mid-life hypertension is a risk factor for dementia. 

• ‘There is strong and consistent evidence for an association of midlife hypertension and the incidence of any dementia in late-life.’ 

Body weight 

• The risk of dementia can be reduced by weight control. 

• ‘Obesity in midlife may increase the risk of dementia and Alzheimer’s disease’

Cholesterol

• The risk of dementia can be reduced by maintaining healthy cholesterol levels. 

• ‘The evidence accumulated to date does not support the hypothesis that preventing or treating dyslipidaemia will help to prevent cognitive decline, AD or other forms of dementia.’
• ‘Dyslipidaemia in midlife (high total cholesterol) may increase the risk of dementia, particularly Alzheimer’s disease.’

Diabetes

• The risk of dementia can be reduced by maintaining healthy blood sugar levels. 

• ‘Evidence […] confirms a particularly strong and consistent association between diabetes in late-life and the subsequent onset of dementia.’ 
• ‘Diabetes in late-life (and probably in midlife) is associated with an increased risk of all forms of dementia, particularly vascular dementia’.