Bitter kola, also known as bitter cola, or Garcinia kola is a tropical tree with many health benefits. The garcinia tree grows across subtropical and tropical moist regions of Africa. It was rumored that Coca-Cola used the extract of bitter kola in making Coca-Cola drinks during their early days. Although they no long used the extract, the name still retains coca cola, which was coined from the bitter cola flavor.
Bitter kola is beneficial for so many health conditions, and is a perennial herbal medicines. In recent times, there has been a surge in demand of bitter cola across Africa, which has led to a hike in the price of the nut. Most people believed that Chinese pharmaceutical companies use it for drug production.
As the name implies, bitter kola is bitter, but leaves a sweet taste when you have chewed and swallowed it. The fruit is usually pale green when it is still unripe but turns orange to red color when ripe. It tastes sour and can set the teeth on stage when you lick much of it.
Health benefits of bitter kola
Bitter kola has been used in traditional medicines to treat diarrhea, gastrointestinal disorders, tooth ache and oral infections, such as Candida, and osteoarthritis. It has been used as component of several nutraceuticals.
Bitter kola is good for preventing Asthma
Bitter kola uses several mechanisms to prevent the onset of asthma, and it has been shown to be effective in managing asthmatic responses. This effectiveness of bitter kola in asthma management is due to the flavonoids and xanthrone present in bitter kola.
The flavonoids and xanthrone present prevent asthma by inhibiting platelet-activating factor, phospholipase A2, and phosphodiesterase. Flavonoids also protect against allergies, inflammation, free radicals, and platelet aggregation. Xanthrones on its side have anti-asthmatic activity by dependently inhibiting the Ca2+ influx induced by either norepinephrine or high K+, suggesting that xanthrone might act as a blocker of both receptor– operated and voltage–dependent Ca2+ channels.
Another way bitter kola stops asthma is by increasing the level of intracellular cyclic adenosine 3’, 5’–monophosphate (cAMP) content through Xanthrone inhibitory effects on cAMP phosphodiesterase.
Garcinia kola is beneficial for managing hypertension
Bitter kola is good for treating heart related complications, including hypertension. This activity is probably due to its potential for reducing blood lipid levels, such as total cholesterol, low density lipoprotein and triglyceride levels.
High lipid levels are risk factor for cardiovascular disease and hypertension. The higher the concentration of low density lipoprotein, the higher the risk of atherosclerosis and subsequently the higher the chances of developing stroke and myocardial infarction. This hypolipidemic activity of bitter kola, and the vasodilation of the arterial vessels through the increased cAMP level is beneficial for reducing blood pressure.
Garcinia kola inhibits viral replication
In traditional medicines, bitter kola have been used to treat various viral diseases such as measles, polio, herpes simplex virus and ocular virus. A study conducted by Obi and colleagues confirmed this traditional claim, and proved that the extract can be used for polio and measles, as well as in treating herpes simplex virus.
During the Covid-19 period, there were speculations that bitter kola is potentially active against Corona viruses. However, this claim is yet to be clinically proven.
May improve glaucoma
Glaucoma remains the most common cause of permanent blindness across the globe. Of the different forms of glaucoma, open-angle glaucoma is the most common form. It is a chronic, progressive, and irreversible optical neuropathy that is characterized by progressive optic nerve degeneration, which affects more than 60 million people worldwide.
Open-angle glaucoma can be treated by lowering the intraocular pressure. Luckily, a topical application of water extract droplets of bitter kola has proved beneficial for lowering the intraocular pressure significantly. This findings has supported the traditional use of bitter kola to treat glaucoma, especially among the developing countries.
In another study, a combine oral administration of garcinia kola and ascorbic acid exhibited a higher intraocular pressure reduction. This shows that garcinia kola possess anti-glaucoma when taken orally and as an eye droplet. This also suggests that while applying bitter kola eye droplet topically, a patient should also eat the bitter kola along with vitamin C for a synergistic effect.
May improve gastritis and gastric ulcer
In recent time, there has been increase in gastritis and ulcer due to frequent exposure to nonsteroidal anti-inflammatory drugs, and the bacterium known as helicobacter pylori. These drugs increase acid secretion into the duodenum through proton pump.
The events that lead to ulcerogenesis are mediated at the parietal cells by the transmitter substances like histamines, gastrin and acetylcholine. These substances, through a common path that involves cyclic adenosine monophosphate (cAMP) and calcium ions, interact with the gastric proton pump (H+/K+ ATPase) which is ultimately responsible for secreting acids into the lumen of the stomach. Histamine appears to be necessary for the action of gastrin and acetylcholine and it is the critical regulator of gastric acid secretion.
The active compound, kolanone protects your stomach from ulceration and gastritis through the blockage of histamine H2-receptors or by inhibition of hydrogen, potassium adenosine triphosphatase (H+/K+-ATPase), or proton pump activity. Another study also demonstrated that garcinia kola, like okra water, possess bactericidal potential against helicobacter pylori, a bacterium responsible for gastric ulceration.
This study makes bitter kola beneficial for ulcer treatment and other gastrointestinal diseases, such as diarrhea and bloated stomach. Another herb with similar of more potent antiulcer activity is cabbage juice. The effectiveness of cabbage juice in treating ulcer have been largely reported by patients who used it to cure stomach ulcers.
Bitter kola is beneficial for treating malaria
Malaria is the prevalent cause of death among the tropical and subtropical African regions. It is caused by different species of plasmodium. Among these species, plasmodium falciparum is the most severe and widely infective specie. These single-celled parasite is transmitted into the body of the host through the bite of female anopheles mosquitos.
The sporozoites, during the plasmodium life cycle, usually moves from the liver to the red blood, attacking and feeding on the red blood cells. This, in a chronic condition may lead to anemia.
Bitter kola, like guava leaves, and monkey sugarcane has been used since olden days to treat malaria. It is usually administered alongside other herbs such as guava leaves, bitter leaf juice and monkey sugarcane.
Bitter cola protects the liver and kidney
Bitter kola is rich in antioxidants, which protect the liver and kidney from the attack of free radicals. Studies showed that Kolaviron, a compound extracted from bitter kola actively protected the liver from liver toxicity induced by antimalaria drugs and from CCl4 induced liver toxicity, making bitter kola of great benefits for protecting the liver from oxidative damage and from the numerous toxic substances which the liver encounters per day in the course of metabolism.
A study conducted by Anyasor and Ajagunna on the ethanolic extract of bitter kola stem bark showed that the plant extract elevated plasma, liver and kidney superoxide dismutase, glutathione peroxidase, and plasma glutathione, while the terpenoid extract of the plant sample modulated hematological markers.
Furthermore, they also showed the terpenoid extract substantially protected against sodium arsenite-induced hepatotoxicity while the ethanolic extract protected against sodium arsenite-induced nephrotoxicity. This studies confirmed the health benefits of bitter kola on the liver and kidney health.
Bitter kola is beneficial for wound healing
Another important health benefit of bitter kola is in wound healing. Bitter kola extract is added in shea butter of any other ointment and applied topically on the wounded surface. But that is not all, when administered orally, bitter kola also proved effective as a wound healing agent.
The active compound, Garcinia hydroxybiflavanonol (GB1) have exhibited strong healing properties in both diabetic and normal persons. According to a study conducted by Nwaehujor and his colleagues, topical application of GB1 caused a significant concentration-dependent reduction in wound diameter and epithelialization period of excision wounds.
According to the study, both the oral and topical application of bitter kola exhibited significant wound healing, which are comparable to Neomycin-bacitracin powder.
Adding garcinia kola seed powder in jute leaf juice may definitely, and synergistically improve wound healing, and reduce the healing time period. The powder and coral tree stem bark powder may also be added to watermelon seed oil, and applied topically on the wounded surface, as watermelon seed possess strong wound healing property.
Bitter kola is used in treating cough
As a home remedy for treating cough, catarrh, and sour throat, the dry seed powder of bitter kola is mixed with natural honey and taken orally. This method have gained wide application in most developing nations, and is relatively cheaper than most orthodox drugs. Also, you can chew the seed with pepper mints for effective cough prevention.
Effect of bitter kola on male fertility
There are believes that bitter kola increase male sexual desire, enhance penis erection and sperm quality. This belief however, is been contested by several studies. Some studies suggest that bitter enhances male libido, increases sperm count and testosterone level, enhances strong erection and boosts male fertility. This may ne a good news, but other studies concluded that ingestion of bitter kola for a long duration resulted in low sperm count, low libido and infertility in male whister rats, suggesting that long consumption of garcinia kola would have a negative impact on the fertility of men.
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