Currently, there is an increase in the number of the world's aging population. This aging process is often connected with cognitive decline of some functions such as memory or speed processing loss. Since Alzheimer's disease cannot be cured yet, considerable efforts are being made to at least delay this cognitive decline among elderly in order to maintain and prolong the quality of their life. This can also be achieved by non-pharmacological approaches such as performing physical activities, cognitive training, or adhering to a Mediterranean Diet (MedDiet). One of the components of MedDiet - extra-virgin olive oil (EVOO) - has considerable health benefits. The purpose of this review is to examine the effect of EVOO intake on the delay of cognitive decline among the elderly. The methodology is based on a literature review of available sources found on the research topic in three acknowledged databases: Web of Science, Scopus, and PubMed. The results of in vitro and in vivo studies indicate that the regular intake of EVOO is associated with enhanced cognitive functions, which means that this oil may have a neuroprotective effect and could positively prevent the development of dementia, especially Alzheimer's dementia. It is believed that secoiridoid oleuropein is responsible for this effectiveness. Furthermore, there is also a need of more randomized controlled studies or longitudinal observational studies to be performed to confirm the efficacy of the beneficial health effect of EVOO on the delay of cognitive decline.

Biomedical Research Centre University Hospital Hradec Kralove Hradec Kralove Czech Republic

Department of Applied Linguistics University of Hradec Kralove Hradec Kralove 500 03 Czech Republic

Department of Chemistry Faculty of Science University of Hradec Kralove Hradec Kralove Czech Republic

Department of Neurology University Hospital Hradec Kralove Hradec Kralove 500 05 Czech Republic

Malaysia Japan International Institute of Technology Universiti Teknologi Malaysia Kuala Lumpur Jalan Sultan Yahya Petra Kuala Lumpur 54100 Malaysi

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