There is accumulating evidence suggesting that olive oil may have a positive impact on conditions involving cognitive deficits, such as MCI and AD. More specifically, these beneficial effects are mostly attributed to some phenolic compounds in olive oil, such as oleocanthal, oleuropein and ligstroside. Oleocanthal is deeper studied than the rest of olive oil phenol components and it shows promising results in neuroprotection against AD through various suggested mechanisms, such as the enhancement of amyloid-beta clearance in the brain and the inhibition of neurofibrillary tangles formation. For this reason, it would be interesting to study the effects of freshly-pressed extra virgin olive oil, as it is known that it contains oleocanthal in higher concentrations than the normal extra virgin olive oil. The aim of the study is to evaluate the beneficial effect of extra virgin olive oil in comparison to freshly-pressed extra virgin olive oil on patients diagnosed with mild cognitive impairment (MCI). Study Type: Interventional Study Design: Allocation: Randomized Intervention Model: Parallel Assignment Masking: Double Blind (Subject, Investigator) Primary Purpose: Prevention
Inclusion Criteria: * Memory Complaints * Abnormal memory function documented by scoring 1 SD below the age-adjusted mean on the Logical Memory II subscale, (Delayed Paragraph Recall) from the Wechsler Memory Scale-R. * MMSE 24-30 * CDR(sum of boxes) \>= 0,5 * Diagnosis: Mild Cognitive Impairment (amnestic plus multi-domain) * Geriatric Depression Scale (GDS) \<6 * Hachinski Modified Ischemic scale \<= 4 * Stability of Permitted Medications for 4 weeks * Years of education: \>= 5 * Proficient language fluency * Have a study partner with 10+ hr/wk contact (can be in person and telephone), accompanies to visits * Compliance Exclusion Criteria: * Visual and auditory acuity inadequate for neuropsychological testing * Enrollment in other trials or studies not compatible with MICOIL * History of significant neurological or psychiatric illnesses or presence of other diseases precluding enrollment. * Use of forbidden medications (listed below) * Ferromagnetic implants and devices (including implants or devices held in place by sutures, granulation or ingrowth of tissue, fixation devices, or by other means) not eligible for MRI scanning. Brain malformation or other conditions that may complicate lumbar puncture Medications across the study Excluded Medication: * Antidepressants with anti-cholinergic properties. * Regular use of narcotic analgesics (\>2 doses per week) within 4 weeks of screening. * Use of neuroleptics with anti-cholinergic properties (e.g., chlorpromazine, thioridazine) within 4 weeks of screening. * Chronic use of other medications with significant central nervous system anticholinergic activity within 4 weeks of screening (e.g., diphenhydramine). * Use of Anti-Parkinsonian medications (including Sinemet, amantadine, bromocriptine, pergolide, selegeline) within 4 weeks of screening. * Participation in any other investigational drug study within 4 weeks of screening (individuals may not participate in any drug study while participating in this protocol).