Introduction

A balanced diet is key to maintaining a healthy lifestyle, but if you are looking to further improve your health, there are a whole host of benefits that natural, unprocessed foods can provide. An excellent example of one is pomegranates.

Pomegranates hold a whole host of beneficial properties aside from being a good source of fruit in your day-to-day life. What may be most surprising is the benefits pomegranates can potentially have on cognitive function, such as memory and neural protection. Cognitive health is vital to quality of life, daily living, and thriving in various environments. By incorporating pomegranates into your diet or meal plans, you could be improving both short-term and long-term health.

Key nutrients

Pomegranates are full of nutrients and vitamins, making them a superfood that can bring about many benefits. Pomegranates are high in:¹

• Vitamin C – Structural support in bones, cartilage, blood vessels, etc.  
• Vitamin E – An antioxidant
• Vitamin K – Blood clotting benefits
• Folate – Red blood cell production
• Potassium – Nerve, muscle (including heart) functionality and moving waste
• Magnesium – Controls blood pressure and glucose levels

Pomegranate also contains positive bioactive compounds known as polyphenols, which are potent antioxidants.² Antioxidant’s main role is the reduction of harmful free radicals in cellular environments. Free radicals are formed as a byproduct of energy production, producing unstable molecules. Antioxidants reduce these free radicals by pairing them with the extra electrons in the free radical’s orbit, causing them to become neutralised and non-damaging.³

These polyphenols also contain anti-inflammatory properties. Polyphenols have been observed to have inhibitory effects on inflammatory enzymes that produce harmful byproducts such as COX-1 and COX-2, also having a similar impact on IL-1β activity ², which is another inflammatory mediator. Polyphenols also inhibit the activation of pathways and processes, such as NFKB transcription and MAPK activity, which inhibit inflammation and prevent its effects.² These benefits are seen throughout the body and aren’t localised to any particular place, meaning the benefits pomegranates can potentially give can be widespread and beneficial.

Further details of what a pomegranate contains can be found at FoodData Central.

Cognitive Benefits

The anti-inflammatory effects found in polyphenols have been observed to have benefits regarding memory cognition in middle-aged and older adults.⁴

Memory loss as you age is a normal phenomenon influenced by oxidation as a result of normal metabolism and inflammation. While there are memory exercises that may prove useful, being able to potentially influence factors relating to memory loss is a huge advantage.

Pomegranate juice helps maintain age-induced memory loss, reducing impairment of visual memory performance. Pomegranate juice also appears to have a short-term effect on verbal memory.⁴ The effect on memory performance was relatively small, most effects on memory were either minor or non-significant improvements. But even minor effects reflected benefits, and considering the other nutritional benefits it provides, it is potentially a good addition to an ageing person’s diet.

The mechanism of action is not yet certain. However, a theory in this paper is that some gut bacteria convert polyphenols to a compound known as urolithins that can enter the brain and affect neural function.^2,4

Another benefit to brain function potentially granted through consuming pomegranate is increased blood flow. Reduced clogging of the arteries increases blood flow across the body, including the brain. Increased blood flow to the brain improves neuronal function and oxygen use within areas related to memory.⁵ Pomegranates, due to their anti-inflammatory effects, are also protective of brain inflammation that occurs due to injury or a decrease in brain function, further helping to improve cognitive function.^4,6

An fMRI study showed that consuming pomegranate juice resulted in significant improvements in memory performance and that the polyphenol metabolites increased only memory areas of the brain, showing direct correlation and specificity. The subjects used had lower memory performance than the norm and showed improvement after a month. These results are predicted to be due to increased antioxidant effects and blood flow into the brain.⁵

One major cognitive benefit that sparked a great amount of research is the benefits pomegranates had on Alzheimer’s disease.

Pomegranate juice has been found to reduce amyloid-beta levels (the hallmark of Alzheimer’s disease), and it helps with memory deficits due to Alzheimer’s, such as in spatial memory, one of the first targeted areas.⁶ It performs these tasks through activation of the PI3K-Akt-mTORC pathway, which opposes the formation of amyloid beta and helps with neuronal function. There is also inhibition of other key pathways associated with APP (amyloid precursor protein) pathologies.⁶

The onset of degenerative disorders like Alzheimer’s may be slowed due to pomegranate and its antioxidant and anti-inflammatory effects. These effects reduce oxidative stress, which is known to progress the disease and is a primary result. This antioxidant protection of cognitive decline helps slow the rate of memory function loss through the prevention of oxidative stress ⁶, a factor in Alzheimer’s disease tau pathology, a major factor in the dysfunction and loss of neurons and neuronal integrity.⁷

Anxiety and depressive disorders are examples of mental health problems that can potentially show improvement when consuming pomegranate. Pomegranate extract has been shown to improve depression and anxiety behaviours. The anti-inflammatory properties in the brain appear to offer potential benefits.⁸

In people with anxiety or depressive disorders, there is an impairment of oxidative stress and inflammatory defence, with increased stress and inflammation being a part of the pathology of either disorder. Pomegranate extracts potentially increase this defensive system through antioxidant enzyme action, thus decreasing pro-inflammatory cytokines.

In this study, there was also a marked increase of serotonin, a key neuromodulator in the brain with a major role in mood, and restoration of the Hypothalmic pituitary adrenal axis (HPA), reversing the depressive and anxiety-like symptoms.⁸

Magnesium deficits are known to cause depression. Restoring a healthy balance may help recovery, especially in the HPA. Pomegranate is high in magnesium. However, the magnesium extracts used were much higher than that of pomegranates.⁸

Future developments

The overall effects of Pomegranate are relatively minor due to the lack of purity, even with extracts. However, the knowledge of the targets involved in pomegranate juice leads to many avenues of research into more potent targets of the pathways that are deemed beneficial. Research into avenues determining characterisation of key chemicals and experimentation with synthetic models could prove incredibly effective in the future, and an increase in human trials determining long-term effects of various cognitive pathways, as well as other bodily functions, would provide a more in-depth description of the value of pomegranate.^2,5,8

Recommendations

Pomegranates are very high in natural sugars.¹ Since too much sugar is well known to have negative consequences, consumption should reflect a broader balanced diet. In the studies done to determine the beneficial effects of pomegranate, they frequently used ~240ml per day of pomegranate juice.^6,9

However, if you already have low blood pressure, it is best not to take them. The intended benefit of controlling blood pressure may result in a reduction, which is unsafe and too low.⁹

It is recommended that you speak to your medical professional beforehand to ensure that a regular intake will not harm you. You may also be unknowingly sensitive to some of the chemicals in pomegranate.

Conclusions

Pomegranates are considered to be a superfood. There are many nutritional benefits that can help improve overall health. However, pomegranate’s true benefits may be yet to be fully discovered and researched.

Already, it has been discovered that there are antioxidant and anti-inflammatory properties that potentially help with a whole host of conditions, from cancer to heart health.² Arguably, the most significant benefit is cognitive health. By taking a relatively small amount of pomegranate juice, it has been discovered that it may slow the rate of cognitive decline and memory loss that comes with ageing. It does this through the use of activating pathways that inhibit inflammation and through its antioxidant effects that limit the damage done by normal ageing metabolism. These effects are neuroprotective and can potentially help with memory both in the short and long term to a minor degree. Most importantly, though, it has been shown to have a potential effect on the development of Alzheimer’s disease and its pathology, leading to memory loss and cognitive decline. Homing in on pathways that are affected by Alzheimer’s disease, pomegranate is able to slow the progression of amyloid beta build-up and tau pathology. The knowledge of how pomegranate may affect pathways is left up to speculation, but with this knowledge, we are able to research potential benefits further, and, more importantly, into new ways to assist progressive disorders and memory deficits, perhaps in a more potent way than pomegranate.

These developments show how nutrition can be beneficial. Planning our diet and food intake can provide positive outcomes in the long term.