Introduction 

An exotic memory-boosting palm fruit or just another tropical myth? Salacca Zalacca, popularly known as the snake fruit or ‘salak’, has been traditionally associated with numerous health benefits including the improvement of immunity,¹ digestion,²  and heart health³ as well as the reduction of malnutrition⁴ and even a reduced risk of cancer.⁴ However, one of the most important benefits of the snake fruit is its ability to enhance cognitive function as a result of its rich and diverse nutritional composition, which includes nutrients such as flavonoids, iron, fibre, and vitamin A.⁴ Cognitive function, broadly defined, is our ability to think, learn and solve problems independently. Beyond boosting a healthy brain, salak has also been reported to elicit protective effects on the brain as it is a rich natural source of antioxidants, pectin, potassium, and vitamin C.^4,5

This article aims to comprehensively separate the facts from fiction and explore the impact of snake fruit on the brain while also outlining safe ways of incorporating it into everyday diet plans.

What is a snake fruit? 

With brown scaly skin, sweet, citrusy flesh, and a poignantly complex smell, the snake fruit has been gaining popularity for its health benefits in recent years. The perennially flowering snake fruit palms are indigenous to Southeast Asia, with the majority of their production originating from Thailand, Malaysia, Indonesia, and Central Java. ⁴ Growing in clusters similar to those seen in coconuts, the cultivation and export of ‘salak’ is no mean feat, as its rough, spiny skin makes it challenging to harvest. Once harvested, the snake fruit rapidly undergoes metabolic changes such as respiration⁶ which is a process by which the sugars in the fruit break down into carbon dioxide and water, leading to a reduction in its edible quality.

Nutritional composition of the snake fruit

The snake fruit is rich in flavonoids, macronutrients, and micronutrients. Flavonoids are a type of plant nutrient that has been extensively reported to help in the prevention of illnesses such as heart disease and dementia.⁷ Macronutrients are the class of nutrients that your body needs in large amounts to perform critical functions such as the production of energy in the form of calories with carbohydrates, fats and proteins being common examples. Micronutrients, as the name suggests, are a group of nutrients that your body only requires in smaller amounts in order to perform vital functions such as growth and development, with some common examples being vitamins and minerals. However, the snake fruit also contains potentially cancer-causing⁸ tannins which combine with important nutrients like carbohydrates and make them unavailable for our body to use.⁹ Both tannins and flavonoids represent two contrasting sides of a group of plant compounds called phenolic compounds.

The nutritional composition of one serving (100g) of snake fruit is as follows.⁴

Snake fruit and the brain

Being a complex and unique species, a multitude of genetic, environmental, and lifestyle factors influence our cognitive functioning.¹⁰ While many of these factors are beyond our control, it is important to note the rapidly emerging evidence for the significant influence of gut health on mood, mental health, and cognition.¹¹ Specifically, three kinds of compounds present in the snake fruit have been strongly associated with positively influencing the health and functioning of the human brain: antioxidants, potassium and pectin.  

Antioxidants and the brain

The human DNA is prone to being damaged through a mechanism known as oxidative stress leading to the eventual death of the cell. Oxidative stress has been identified as a key culprit in a number of brain-related degenerative diseases like Alzheimer’s Disease,¹² Parkinson’s disease,¹³ and Huntington’s Disease¹⁴ since the human brain innately has a high energy demand (which produces oxidative stress-inducing chemical species) and a poor ability to make antioxidants on its own. Therefore, antioxidants being incorporated into our diets help combat oxidative stress¹⁵ through intricate mechanisms that are still under rigorous investigation. 

Flavonoids, a type of antioxidant present in abundance within a single serving of the snake fruit, have specifically been used as a therapeutic agent for the treatment of early-stage degenerative brain disease.¹⁶ Therefore, incorporating the snake fruit into our everyday diet as a supplement could potentially have protective effects on these brain-related diseases even prior to their existence, although further research needs to be done to establish the existence and extent of this effect.

Pectin, potassium, and the brain

Pectin is a naturally occurring plant carbohydrate that is present in a substantial amount within a single serving of salak. Mice studies have indicated that dietary pectin not only has a significant effect on reducing depression but also indirectly causes the enhancement of memory formation by regulating the immune system of our body.¹⁷ Further,  increased potassium intake in mice has been reported to improve cognitive functioning as well as slow down the progression of Alzheimer’s Disease.18 However, it is to be noted that until a targeted and extensive investigation has been conducted on human subjects, the translatability of such results in human beings remains unclear.¹⁹

Does the snake fruit help boost memory or brain health?

Despite being at the forefront of neuroscientific inquiry for decades, the brain mechanisms that bring about the emergence and loss of animal memory are sparsely understood. Therefore, even though many isolated components within the snake fruit have been hypothesised to possess numerous health benefits as described above, it would be speculative at best and dangerous at worst to conclusively assume that snake fruit has any meaningful impact on boosting memory or protecting from dementia due to the immensely complex and dynamic nature of the biological mechanisms within both the human body and the snake fruit. However, one thing that can be conclusively said is that the consumption of snake fruit in moderation could definitely replenish the body with some essential nutrients it needs for healthy functioning. 

How do you eat snake fruit? 

Although the appearance of this serpentine scaly fruit may seem intimidating at first, you will have no trouble  treating yourself to the sweet delight of the snake fruit if you keep the following points in mind:

• Ensure the freshness of the salak before eating especially if it is consumed in warmer climates. An easy way to tell if the snake fruit has gone bad is to check for a sharp, fermented smell. It lasts at room temperature for a few days, but the shelf life can be increased to up to 2 weeks if refrigerated.
• How do you prepare the fruit?
  • Break through the top of the scaly exterior using a knife and start peeling away similar to an orange.
  • On removal of the skin, find and remove the brown seeds in each lobe of the snake fruit.
  • After the removal of the skin and seeds, get ready to enjoy the sweet and sour flesh of the snake fruit!

See this for a quick video tutorial on how to prepare and eat the snake fruit. 

Side effects and precautions 

Although incorporating snake fruit into the everyday diet is perfectly fine in moderation, there are some potential side effects and important precautions to be taken:

• The high fibre content present in the snake fruit could potentially cause digestive problems with constipation, bloating and flatulence being common indicators of its excessive consumption.
• It is crucial to peel and deseed the salak prior to consumption as the skin and seeds are toxic in nature. However, some synthetic products such as kombucha tea process the salak seeds to remove the natural toxins and produce a nutritious and refreshing drink!

Conclusion 

Snake fruit is a delicious tropical fruit that has potential general health benefits if incorporated into the everyday diet in moderation but there is sparse evidence at the moment to conclusively suggest that it can have a significant influence in improving human memory or protecting from neurodegenerative conditions such as Alzheimer’s Disease, Parkinson’s Disease or Huntington’s Disease. However, the investigation of the health benefits of culturally significant indigenous fruits like salak promises to be a domain of exciting and emerging neuroscience research.