In a recent study published within the Journal of Alzheimer’s Disease, researchers investigated the mild cognitive impairment (MCI) outcomes of pomegranate seed oil (PSO) interventions. The study included 80 participants divided between cases (PSO + Mediterranean Food regimen [MeDi]) and controls (only MeDi), all subjected to an intensive set of neurological assessments following a yr of their respective interventions. Study findings revealed that participants consuming PSO display significantly higher global cognition, memory, information processing, and executive functions than their MeDi-only counterparts. These findings highlight the usage of PSO by individuals with MCI as a consequence of its safety, ease of availability, and cost-effectiveness in comparison with synthetic pharmaceutical interventions.

Study: The Effects of Pomegranate Seed Oil on Mild Cognitive Impairment. Image Credit: Tim UR / Shutterstock

Pomegranate – an understudied natural food with untapped modern medical potential

‘Pomegranate’ (Punica granatum) is the common name of a fruit-bearing deciduous shrub belonging to the family Lythraceae, subfamily Punicoideae. It’s wealthy in polyphenols and fatty acids with known anti-inflammatory and antioxidant properties and has been utilized in traditional medicine for hundreds of years. Unfortunately, modern research on the plant stays lacking, with only a handful of papers discussing its medical potential, all of which have researched the advantages of pomegranate juice.

Encouragingly, the limited clinical evidence of pomegranate’s effectiveness has been positive, especially within the neurological sphere, with studies finding that pomegranate juice consumed consistently for 12 months resulted in significantly improved verbal memory performance in comparison with abstaining from the juice. Cellular studies using murine models have further revealed that pomegranate juice can inhibit and even reverse neurotoxicity induced by aluminum chloride (AlCl3), leading to higher body weight, learning, spatial memory, and neurotransmitter outcomes. Surprisingly, these effects were noted even at low concentrations of pomegranate juice, attesting to its potent neuroprotective effects.

Mild cognitive impairment (MCI) refers to a period characterised by subtle memory loss and cognitive decline that doesn’t interfere with day by day functioning and is thus hard to detect without specialized clinical assessments. It precedes the rather more significant cognition loss related to dementia and Alzheimer’s Disease (AD) and forms a critical transition point during which period the onset of dementia and AD can either be delayed or hastened. Despite intensive recent research broadening our understanding of those neurological conditions, no cure for these conditions has hitherto been discovered, highlighting prevention as the very best means to combat these diseases.

Oxidative stress has been identified as crucial within the pathology of most neurological and cognitive conditions. An increased adherence to suboptimal health behaviors, particularly weight loss program (e.g., the Western Dietary Pattern), has hence been implicated within the rising global prevalence of AD. Science is increasingly turning to food and dietary patterns as potential prevention interventions against cognitive decline. The Mediterranean Dietary Pattern (MeDi) is one such intervention – characterised by a predominantly plant-based weight loss program wealthy in healthy fats and low in processed foods and red meats; it has been shown to enhance physical and cognitive parameters significantly in preclinical trials.

Elucidating the consequences of pomegranate seed oil (PSO), the a part of the plant richest in potentially helpful, antioxidant-containing nutraceuticals (conjugated fatty acids reminiscent of linolenic acid), would allow for yet one more preventive intervention to combat and delay the onset of those devastating diseases. Unfortunately, no studies have yet explored the advantages of PSO in human models.

In regards to the study

The current study goals to judge the potential impact of PSO on the age-associated cognitive outcomes of individuals with clinically diagnosed MCI. The study cohort initially comprised 100 Greek participants with neurologist-validated MCI as per the MCI definition of the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-V 2013). Unfortunately, 20 participants failed to finish the study during follow-up and were hence faraway from the analyses.

Data collection comprised demographic records (gender, age, education), blood collections, clinical examinations, neuropsychological assessments, and laboratory imaging procedures carried out by neurologists from the Greek Association of Alzheimer’s Disease and Related Disorders (GAADRD). Individuals with hearing deficits, visual impairments, and people currently prescribed antipsychotic medication were excluded from the study. The remaining participants were divided into case (five drops of PSO per day + MeDi) and control cohorts (only MeDi), each with 40 participants.

Extracted blood was used for blood marker discovery and included evaluations of Aβ, tau protein, and phospho-tau protein, known biomarkers for brain damage. Baseline neuropsychological assessments were presented in two 2-hour-long sessions, repeated after six and 12 months to check within- and between-group cognitive performance changes over these time durations. These assessments were chosen to judge attention, memory (working and episodic), visuospatial, executive, and functional performance and were computed using the Alzheimer’s Disease Assessment Scale-Cognitive Subscale (ADAS-cog), the Mini-Mental State Examination (MMSE), and the Montreal Cognitive Assessment (MoCA).

Memory, specifically, was estimated using the Rivermead Behavioral Verbal Learning Test (for episodic memory), the Rey Auditory Verbal Learning Test (RAVLT; for immediate and delayed recall), and the Rey-Osterrieth Complex Figure Test (for visuospatial memory and executive function).

“The Functional Cognitive Assessment Scale (FUCAS) was used to evaluate functionality in day by day living. Nevertheless, this test was used only to support that our patients had no problems in activities of day by day living.”

Study findings and conclusions

Demographic data revealed that the 80 participants included had a mean age of 69.53 years and were 60% female. Comparing demographic data between case and control cohorts showed no statistically significant difference, allowing for between-group comparisons.

Five drops of PSO consumed together with MeDi over a yr were found to guard against cognitive decline significantly and, in some cases, even improve cognitive performance within the case-cohort. In contrast, the control cohort (only MeDi) displayed either no change from baseline or cognitive reductions over the identical period, highlighting the neurological advantages of PSO.

PSO improved visuospatial abilities, executive function, processing speed, learning, verbal episodic memory, and, importantly, global cognition. ADAS-cog, TMT B, and RAVLT scores were all found to enhance statistically over baseline values within the case-cohort. Much more encouragingly – with MoCA presenting the only exception, all neurological parameters measured showed improvements over baseline, albeit these weren’t statistically significant. This highlights the role of PSO in each protecting against cognition loss and in improving some neurological parameters, thereby reversing MCI.

In contrast, with FUCAS being the only exception, all neurological parameters measured within the control cohort displayed declines in mean scores over the 12-month period. FUCAS results were consistent between each cohorts and remained indistinguishable from baseline measures. This, nonetheless, is predicted because MCI’s cognitive deficits don’t typically interfere with day-to-day activities.

“In conclusion, due to the absence of clinical trials regarding the consequences of PSO on cognition of patients with MCI or other cognitive disorders, the aim of the current study was to discover the potential advantages of PSO in MCI. After one yr of treatment, it’s proved that the PSO could be helpful for individuals with MCI improving different domains of cognition. So, the innovation of the current study is that these results can expand the research on this field and encourage the usage of PSO in holistic approaches that could be helpful even within the stage of MCI and result in prevention of dementia.”