Cognitive Function Improvement With Oranges

  • Ka Yin Chan BSc Cognitive Neuroscience and Psychology, University of Manchester

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Cognitive functions are very important as we use our brains every day. I believe many of you have wondered what kind of food improves your cognitive functions like memory, attention, and processing speed. But have you ever thought if oranges can also benefit your cognitive function? 

Oranges are rich in nutritional content including vitamin C, flavonoids, and other antioxidants. These nutrients help improve your cognition in different ways. Other than memory improvement, studies have shown that drinking orange juice also improves psychomotor speed, attention, and alertness. 


Importance of cognitive function

Cognitive functions are vital for us as we utilise them every day. Cognitive function is a broad term that means the mental processes related to making decisions using our knowledge and the information available in our environment. There are different aspects of cognitive function, including memory, both short-term and long-term, attention, alertness, learning, decision-making, and language abilities. 

What affects your cognitive performance?

There are several factors affecting your cognitive performance where age is the major risk factor. Ageing of the brain means that there is a loss of brain volume and neurons leading to cognitive decline. Neurodegenerative diseases like Alzheimer’s disease and Parkinson’s disease also lead to cognitive decline. There are also other factors affecting your brain health as you age such as oxidative stress and neuroinflammation. 

Oxidative stress

Oxidative stress refers to the imbalance between oxidants and antioxidants. It has been suggested that there is a strong correlation between oxidative stress and cognitive impairments during ageing. Oxidative damage during ageing negatively affects learning and memory as it promotes neuronal degeneration which in turn increases the possibility of dementia. Studies have also found that markers for oxidative stress can be used as biomarkers in Alzheimer’s disease which means that high levels of oxidative stress can be predictive for Alzheimer’s disease. 


With the increase in age, the risk of neuroinflammation also increases. Neuroinflammation causes a range of reactions and leads to magnification of the central nervous system’s deterioration. This could accelerate cognitive impairment. Although inflammation can facilitate the healing process, damage to cells and tissues can be a result of prolonged inflammation. Studies have also discovered that there is an association between increased levels of inflammation, neurodegeneration, and impaired neurogenesis. This means that there would be neurons dying while the formation of new neurons is impaired hence worsening your cognitive functions. 

Oranges as a potential cognitive enhancer

Oranges are one of the citrus fruits that are rich in nutritional value. They have lots of potent antioxidants such as Vitamin C and flavonoids which are good for brain health and cognitive decline. Also, oranges are affordable and easily found in supermarkets. Consuming an orange every day can prevent cognitive decline and improve your cognitive functions in terms of memory, attention, and executive functions. 

Nutritional components of oranges

Vitamin C

Oranges are rich in vitamin C. Every 100 g of oranges provides 59 milligrams (mg) of vitamin C which means that a medium orange provides approximately 83 mg of vitamin C. The suggested daily intake of vitamin C for people 75mg and 90 mg respectively. As you can see, eating an orange every day is already sufficient for daily consumption of vitamin C. Now you may wonder how vitamin C improves cognitive functions. 

First of all, vitamin C plays a crucial role on a neuronal level. It modulates different systems and facilitates plenty of processes in the brain. Studies have shown that comparing healthy participants and cognitively impaired individuals, such as those with Alzheimer’s and dementia, healthy participants have higher concentrations of vitamin C than those with cognitive impairments. 

Moreover, vitamin C is also an antioxidant that protects your cells from free radical molecules. When there are too many free radical molecules, they damage the cells and tissues. Therefore, vitamin C is very important when it comes to neurons in the brain. 

Other than the antioxidant property of vitamin C, it also has several non-antioxidant functions. It helps reduce the amount of metals, for instance, iron and copper, in the brain. Although metals in the brain regulate neurotransmission and antioxidant response, when they are in excess, it can lead to metal toxicity which impairs different enzymatic reactions and hence disrupt normal brain functioning. Excessive metals in the brain also correlate with neurodegenerative diseases, for example, Parkinson’s disease, Huntington’s disease and Alzheimer’s disease. It has been reported that high levels of iron were found in the brains of patients with Alzheimer’s disease. 

Therefore, vitamin C not only facilitates neuronal communication in the brain, it also protects the brain from oxidative stress and metal toxicity. Hence, vitamin C is very beneficial to your cognitive function. 


As mentioned above about the antioxidant property of vitamin C, other than vitamin C, oranges have an array of antioxidants, such as flavonoids, carotenoids and many other phytochemicals. 


Firstly, there are over 60 flavonoids in one orange. In sweet oranges, the dominant flavonoids are hesperidin and narirutin and in sour oranges, the dominant flavonoids are neohesperidin and naringin. Flavonoids, just like vitamin C, are antioxidants. They help protect the brain from the damage of free radicals. Apart from this, they also have other properties, like anti-inflammatory, anticancer and antiviral.

Now you may ask how these properties relate to cognitive performance. Well, studies have shown that flavonoids are able to improve cognitive functions as they are neuroprotective. They enhance neuronal function and stimulate neurogenesis which means they facilitate the formation of new brain cells. 

Nevertheless, due to their anti-inflammatory property, it is also suggested that they can help reduce cognitive decline as they interact with the signalling pathways that are responsible for the mediation of neurodegeneration and neuroinflammation. 

In addition, experiments done in rat brains also revealed that flavonoids are able to cross the blood-brain barrier in areas related to learning and memory. In short, flavonoids are beneficial to your cognitive function by protecting the brain from cell damages and promoting the formation of new brain cells. 


Secondly, just like flavonoids, carotenoids are also antioxidants and anti-inflammatory. Studies have performed an analysis on whether carotenoids are related to cognitive performance improvements. They have found that with the consumption of carotenoids, participants had better cognitive performance. Due to their neuroprotective function, they also protect the brain from oxidative stress and facilitate synapses between neurons. 


Thirdly, phytochemicals are suggested to be beneficial in improving cognition such as alertness, attention, memory and executive function. Although their direct effects on cognitive performance are relatively weak, long-term consumption of phytochemicals can improve brain health and they also modulate cerebral blood flow. 

Incorporating oranges into your diet

Fresh oranges

Oranges are rich in vitamin C and antioxidant protection

Dietary fibre Dietary fibre decreases the chances of constipation and helps maintain bowel health.

Heart health and blood pressure Oranges contain potassium which can lower blood pressure and reduce the risk of cardiovascular diseases

Oranges contain vitamin C and folate which provide support to different immune cells which is helpful in modulating oxidative stress and inflammation.

Recommended daily intake

The recommended daily intake of fruit and vegetables is at least 5 portions of 80 g per day. 

Orange juice

Orange juice works just like fresh oranges which is a good source of vitamin C and antioxidants. What is more, is that it is more convenient than fresh oranges as it is readily available. However, orange juice is often high in sugar content. It also lacks the fibre found in fresh oranges as it has been processed. 

How to choose healthy orange juice options

When you are looking for orange juice, there are a few things you should pay attention to. You should look for orange juice that is 100% pure as this indicates that it does not contain any chemicals such as artificial flavours and preservatives. You should also check for the sugar content so that you do not consume too much sugar in your diet. You can also choose the ones that are pasteurised, which means it is heat-treated to kill bacteria, and fresh-squeezed, which is minimally processed and retains more minerals and vitamins. Lastly, it is entirely up to you to choose the one with pulps or no pulps. They both have their benefits pulps give you more dietary fibres whereas no pulps give you a smoother texture.

Additional tips for cognitive function improvement

 You must have a well-rounded diet for your brain health. For example, apart from consuming enough vitamin C and antioxidants, you should also stay hydrated. It is suggested to consume 6 to 8 glasses of fluids (water, sugar-free drinks, and low-fat milk) every day. Studies have shown that mild dehydration can also lead to impairment in cognitive performance. Physical exercise can also improve your cognitive performance and can be protective for neurodegeneration. 


It is important to take good care of your cognitive functions early on as ageing is the primary risk factor of cognitive decline. Oranges are extremely beneficial to your cognitive functions as vitamin C and antioxidants in oranges help protect your brain from neuronal degeneration and facilitate interactions between neurons. To incorporate oranges in your diet, you can either consume fresh oranges or drink orange juice. But bear in mind that you also need a healthy diet and lifestyle to protect your cognitive functions and prevent cognitive decline. 


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Ka Yin Chan

BSc Cognitive Neuroscience and Psychology, University of Manchester

She is a Neuroscience student with strong interest in clinical research and medical communications. She believes that the ever-growing field of scientific research is crucial for understanding health and hence improve it. presents all health information in line with our terms and conditions. It is essential to understand that the medical information available on our platform is not intended to substitute the relationship between a patient and their physician or doctor, as well as any medical guidance they offer. Always consult with a healthcare professional before making any decisions based on the information found on our website.
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