Previous research has shown that physical activity can slow down or prevent functional decline associated with aging and improve health in older individuals.^1,2 However, regarding Alzheimer disease (AD) or dementia, the relationship is less clear, with many studies reporting exercise being associated with lower rates of cognitive decline^1,3 or dementia^4-7 and others reporting no significant association.^8-10 Dietary habits also may play an important role but epidemiological data on diet and AD have been conflicting.¹¹ In this cohort, we previously found that higher adherence to a Mediterranean-type diet is associated with lower risk for AD^12,13 and mild cognitive impairment.¹⁴

The concept of cognitive reserve (CR) suggests that innate intelligence or aspects of life experience like educational or occupational attainments may supply reserve, in the form of a set of skills...

The concept of mild cognitive impairment (MCI) was developed to identify subjects who are in the transitional stage between normal aging and dementia or Alzheimer disease (AD). Because of the high conversion rates, subjects with MCI constitute a population suited for study of dementia-AD risk factor epidemiology and for investigation of possible behavioral or pharmacological preventive interventions. Among behavioral traits, diet may play an important role in the cause and prevention of AD. However, epidemiological data on diet and AD have been conflicting.^1,2 Moreover, there is a paucity of research on the effect of dietary factors on both rates of development of MCI and rates of MCI conversion to AD.

Epidemiological evidence linking diet, one of the most important modifiable environmental factors, and risk of AD is rapidly increasing. However, current literature regarding the impact of individual nutrients or food items on AD risk is inconsistent, partly because humans eat meals with complex combinations of nutrients or food items that are likely to be synergistic.¹ As an alternative approach, dietary pattern (DP) analysis has emerged in recent years.^1,2