Cocos nucifera L.
Coconut grows in tropical regions and has a great importance in the islands of the Pacific Ocean. It provides all daily needs of the people including food, juice, oil, medicine, fiber, fuel, etc. In this region, it is called “heaven tree” or “life tree”. Origin of the coconut is the Southeast Asia and by it expanded to tropical regions. Entrance of the Europeans to the Pacific Ocean regions in 19th century led to commercialization of this plant and changed the coconut oil to the first vegetable oil in the global trade
1. Regulating Blood Glucose Levels
In 2015 a research with the purpose of investigating the effects of the coconut oil on the lipid profile of the patients with Coronary Artery disease (CAD) was performed in Brazil. In this research 116 male and female patients suffering from CAD with the average age of 62 consumed non-processed coconut oil for three months and after this time their waist and neck size and BMI were measured. The results showed that consumption of coconut oil caused a reduction in BMI and waist size and increased HDL (good cholesterol). Researchers believe that polyphenols and vitamin E of coconut are responsible for this reduction.
The results of another research which was performed to evaluate the effects of coconut oil on lipid profile of the Filipino women aged between 35 to 69 years in 2011 showed that consumption of coconut oil increased the amount of good cholesterol level (HDL). Average of total cholesterol level, LDL and triglyceride were in the desirable range announced by the World Health Organization (WHO) before consumption of coconut oil, but the low level of HDL demonstrated that they were exposed to cardiovascular disorders. The level of this type of cholesterol in these women increased after consumption of coconut oil.
2. Regulating Blood Pressure
In a research that its results were published in the Journal of Ethnopharmacology in 2011, the effect of ethanolic extract of the coconut fruit on controlling high blood pressure originated by DOCA salt (a substance which is used to induce high blood pressure in experiments) in rats was investigated and the results showed that consumption of coconut fruit caused a reduction in average systolic blood pressure in these rats. Researchers believe that the reason of this activity is due to Chlorogenic acid polyphenols, vanillic acid and frolic acid existing in this extract. The findings showed that the effect of coconut extract on loosening the veins and reducing blood pressure through production of nitric acid is due to direct activation of nitric acid/ Guanylate cycles pathways, stimulation of muscarinic receptors or Siclo-oxinage pathways.
In a research that was performed in 2016, the effect of a coconut juice on reduction of blood pressure of adult women ranged between 30 to 60 years that suffered from step 1 blood pressure was evaluated. According to the results this drink reduced systolic and diastolic blood pressure significantly. This is because of active biologic ingredients in coconut which have antioxidant effect.
3. Regulating Blood Glucose Levels
In 2013, the results of a research were published in European Journal of Integrative Medicine in which the effect of coconut juice on carbohydrate metabolism and pancreas pathology in rats which were diabetic by injection of alloxan was investigated. These rats received 4mg coconut juice per 100grams of body weight orally for 45 days. The effect of coconut juice on blood glucose level, a1c hemoglobin ( a1c hemoglobin test demonstrates the level of blood glucose along with blood hemoglobin and the average of patient’s blood glucose level in the past 2 to 3 months), liver glycogen, carbohydrate metabolisms and liver enzymes was investigated. The results showed that oral consumption of coconut juice in diabetic rats caused a significant reduction in blood glucose level and A1C hemoglobin and improved the level of insulin in plasma and increased the liver glycogen and activity of carbohydrate metabolism enzymes. Also, consumption of coconut juice, reduced liver damage caused by Alloxan and reconstructed beta cells in diabetic rats. In addition consumption of coconut juice caused a reduction in the activity of glucose-6- Phosphatase and Froktuz-1 and 6- base phosphatase enzymes that can be due to an increase in insulin concentration.
In diabetes induced by Alloxan, the level of ALP, SGOT and SGPT enzymes (Liver enzymes) in blood increases that are caused by liver damage due to free radicals originated by Aloxan. By consuming coconut oil, the activity of these enzymes in rats reduces that is the indicative of the repairing of toxic effects of Alloxan on liver.
Furthermore, Chemical analysis of coconut juice showed that this substance contains l-arginine, ascorbic acid, minerals and etc. that altogether play roles in balancing glucose metabolism and sensitivity to insulin. Recently, it has been reported that l-arginine is able to regenerate beta cells in pancreas and can reduce liver damage in rats. Also, magnesium and potassium that are minerals existing in coconut juice are effective in reducing blood glucose level.
4. Promoting Weight Loss
Most of the human studies that have been performed about consumption of coconut oil indicate the effect of this substance on improving lipid profile. In a research, the effect of coconut oil on abdominal obesity was investigated in 40 women who ranged between 20 to 40 years old and randomly received 30 ml coconut oil for 12 weeks and at the end of the trial, it was revealed that consumption of coconut oil causes an increase in HDL, a decrease in LDL, a reduction in BMI and a reduction in the waist size. In another experiment, a significant reduction in the waist size of 20 healthy people who received 30ml coconut oil daily (half an hour before meals) was observed. In this research, lipid profile didn’t change significantly but the amount of creatinine and alanine aminotransferase was reduced.
Most of coconut oil is comprised of medium- chain triglycerides (MCTs). Researches have shown that substituting calories with these triglycerides and without receiving additional calories can cause a low but significant increase in reduction of body fat. This effect is more obvious in overweight people. Also coconut oil can increase the metabolism in rats, the speed of fat breakdown and releasing fatty acids (lipolysis process) temporarily.
5. Improving Liver Function
Trimethoprim-sulfamethoxazole (TMP-SMX) is an antibiotic that is used frequently but its usage is along with bad effects. In a research that was performed to investigate the raw coconut oil on effects originated by TMP-SMX, 20 rats were divided in four groups (control, receptors of TMP-SMX, receptors of coconut oil and receptors of TMP-SMX and coconut oil). The results showed that TMP-SMX caused an increase in bilirubin, lactate dehydrogenase and alkaline phosphatase (ingredients which their increase in blood is harmful) in blood plasma. Consumption of coconut oil modified the effects induced by TMP-SMX through restoration of total level of bilirubin, alkaline phosphatase and lactate dehydrogenase. Researchers concluded that active ingredients of coconut oil have a protective effect against toxicity originated by using TMP-SMX particularly in the liver of the rats.
In another research, the protective effect of coconut juice on the liver of the female rats poisoned by ccl4 (carbon tetrachloride) was investigated. CCL4 caused an increase in glutamate oxaloacetate transaminase and glutamate pyruvate transaminase in serum and also liver necrosis and creating fatty liver, while in rats which received coconut juice, the reduction of these enzymes was observed.
6. Improving Cardiovascular System Function
In order to investigate the effect of coconut juice on cardiovascular function, a research was done in 2015, and its results were published in International Journal of Biochemistry Research & Review. In this trial, 25 adult Albino rats were divided in five groups. Except one group which was control group, the other groups received different doses of coconut juice (0.5, 1, 1.5 and 2 ml per kilogram of body weight). In this research, lipid profile was considered as an index for cardiovascular function. According to the findings, consumption of coconut juice caused an increase in SOD enzyme (an antioxidant) and a reduction in Malondialdehyed (MDA) (indicative of lipid peroxidation). Also this drink reduced the level of total cholesterol level, triglycerides and LDL, while the level of HDL increased. These effects were dose-dependent. In researchers’ opinion, reduction of MDA after consumption of coconut can be due to an increase in the activity of glutamine peroxidase and other antioxidant systems in the body.
Other researchers observed protective effect of coconut on cardiovascular system and related this effect to the presence of mineral ions in this fruit (particularly potassium). Also raw coconut oil contains a large amount of phenolic ingredients which are responsible for its antioxidant and anti-inflammatory effects and cause this oil have a high potential in prevention of lipid peroxidation. These effects of coconut oil altogether are protective factors of cardiovascular system and its function.
7. Improving Kidney Function
Disorder in kidney function is one of the problems that are probable in diabetic patients. Because of this reason, a research was performed to investigate the effect of raw coconut oil on kidney function in diabetic rats in 2014 and its results were published in Physiology Journal. In this research, Wistar Albino rats were diabetic by injecting Alloxan and the level of disorder in kidney function was measured through testing the level of their protein, and also creatinine, urine and blood urine nitrogen. The results showed that this oil (about 10% of the diet) compensated the reduction of blood nitrogen caused by diabetes. It caused a reduction in creatinine, urine and urine nitrogen in blood. Researchers attribute this effect to the antioxidant effect particularly lauric acid of this fruit. Findings show that consumption of raw coconut oil can improve destructive effects of diabetes on kidney.
Another research which its results were published in Journal of Gastrointestinal and Digestive System in 2012 showed that coconut juice had a protective effect on the kidney of diabetic Wistar rats. In this study, the effect of coconut juice on body weight and function of kidney was evaluated and the results showed that in rats which were diabetic by Alloxan, the level of urine, creatinine, potassium, sodium and bi- carbonate was increased, while through consumption of coconut juice, their level was reduced. These findings show that consumption of coconut juice can be helpful in kidney disorder in diabetic patients.
8. Alleviating Peptic Ulcer Disease
In order to investigate the effect of ethanolic extract of coconut on gastric ulcer induced by Aspirin in Wistar rats, a research was done in 2017 and its results were published in Journal of Gastrointestinal and Digestive System. In this trial, rats were treated by different doses of the extract for 14 days. The results showed that coconut extract could improve gastric ulcer (the best result was achieved in 400mg per kilogram body weight) and cause a reduction in oxidative stress. Since coconut contains large amounts of l-arginine and vitamin C, it can protect body organs against oxidative tension and by increasing antioxidant enzymes reduce the level of free radicals and lipid peroxidation. In this research, coconut extract caused a reduction in the number of inflamed cells and necrosis in stomach tissue and an increase in activity of SOD antioxidant enzyme. Researchers concluded that consumption of ethanolic extract of coconut can be a reliable and affordable method in treating gastric ulcers in patients who consume Aspirin.
The results of a research that was published in AJFAND Journal in 2010 showed that coconut extract had a positive effect on rats which suffered from gastric ulcers through consumption of Indomethacin. Gastric ulcers is created by stomach mucous covering damage and it can be due to high secretion of hydrochloric acid (which exists in stomach naturally), infection caused by helicobacter pylori, or high consumption of anti-inflammatory non- steroid drugs such as Indomethacin, Aspirin or Ibuprofen. In this research, the coconut extract to the level of 65/4% and 67/9% respectively caused a decrease in gastric ulcers but its density increased gastric ulcers. These findings show that coconut extract can be helpful in treating gastric ulcers only in low doses. In this study the effect of coconut extract in treating gastric ulcers was similar to the effect of Ranitidine medicine.
The largest amount of medium-chain fatty acid (MCFA) existing in coconut is related to lauric acid that includes about 50% of its fat content. MCFAs and their derivatives have lipid coverage and are effective in destruction of a wide range of bacteria and for example they can remove bacteria which cause gastric ulcers, sinusitis, tooth decay, food poisoning and urinary tract infection. Also coconut oil is effective in fighting against all types of viruses that have lipid coverage (e.g. Vysna, Leukemia, Pneumonia and Hepatitis c viruses). MCFA existing in coconut oil remove these organisms by destructing their membranes. Among fatty acids, laurik acid has a more antimicrobial property.
Anti-fungal property of coconut against Aspergilus, Penicilium, Koldosporium, Forazium and other species has been observed in researches. Researchers have reported two different anti-fungal effects that are as follows: inhibition of spore germination and inhibition of radial growth. Raw coconut oil has been used in treating candida fungal infection. Researchers investigated sensitivity of candida isolates against raw coconut oil and fluconazole and observed that candida Albinex at the minimum inhibition concentration (MIC) of 25% showed 100% sensitivity to coconut oil, while fluconazole showed 100% sensitivity in 64 mg /ml of MIC. Capric acid had the fastest and the most influential effect in removing species of Candida Albinex.
Results of a study which was published in Pharmaceutical Biology Journal, suggest that raw coconut oil has an anti-inflammatory and pain killer effect. This effect was observed in rats suffering from gastrointestinal inflammation originated by Ethyl Phenyl Pyropyvlat. The results showed that this oils have an inhibition effect on chronic inflammation which happened by reduction of forming granuloma (inflammatory mass in tissue) and activity of Alkalyn phosphatase in blood serum.
11. Relieving Arthritis Pain
In 2014, the results of a study were published in International Immunopharmacology Journal in which the effect of raw coconut oil on prevention of Arthritis (joint inflammation) through antioxidant and anti-inflammatory effects in rats was investigated. Coconut oil in dose of 80 mg /kg showed a high percentage of edema prevention in 21st day. Consumption of coconut oil caused a reduction in expression of inflammatory genes such as COX-2, TNF-α and IL-6, density of “reactive or Thiobarbituric acid substances” and an increase in antioxidant enzymes. Inhibition activity of coconut oil can be due to its ability in neutralizing oxidative damages originated by nitric acid.
Also lipid peroxidation is one of the important mechanisms in Rheumatoid. Analysis of “reactant or thiobarbituric acid substance” (TBARS) is a usual method for investigating lipid peroxidation in tissue. In this trial, increase of TBARS was observed in rats with Rheumatoid, which decreased significantly after treatment by coconut oil. Coconut oil reduced the level of inflammation through prevention of formation of free radicals. These results show that occurrence of rheumatoid arthritis can be due to lipid peroxidation and coconut oil has a therapeutic effect on this disease since it prevents lipid peroxidation.
12. Increasing Fertility
In 2014, the results of investigating the effect of coconut juice on serum density of some sex hormones (testosterone and FSH) in rats were published in JKIMSU Journal. In this research, 20 Wistar Albino rats were randomly divided in two groups. The first group was control group and the second group received 3ml coconut juice daily for 28 days. The findings showed that consumption of coconut juice caused an increase in testosterone hormone, FSH and LH and a reduction in prolactin. Increase of the mentioned hormones after consumption of coconut oil is due to stimulation of making and releasing them in ovary / pituitary gland because of ingredients in coconut juice. These results show that consumption of coconut juice can improve reproductive function and boost fertility.
13. Strengthening Bones and Joints
In a research which was done in 2012 and its results were published in Evidence-Based Complementary and Alternative Journal consumption of raw coconut oil prevented bone loss in rats suffering from osteoporosis after menopause. In this experiment three months female rats which received 8% more coconut oil in their diet for 6 months had more bone mass and trabecula number bone strings in comparison to the control group. Coconut oil was effective in maintaining bone structure and preventing of bone loss in rats with lack of estrogen.
The effect of this oil on bone structure was better than treating with calcium, since calcium just prevents the reduction of Trabecula interval but it can’t increase bone mass and Trabecula number. Also coconut oil contains a large amount of saturated fat in the format of medium- chain triglycerides (MCT) that are important for absorbing calcium from intestine. Positive effect of raw coconut oil on bone density can be due to existence of phenol ingredients and direct antioxidant activity and balancing osteoblasts (a group of bone cells that are responsible for making bones) function.
Alkaloids, Glycosides, Saponins, Resin, Steroids, Terpenoids, Vitamins, Minerals, Phenolic compounds such as Catechins, Epithecines, Tannins and Flavonoids; Fatty acids such as Caprylic acid, Lauric acid, Palmitic acid, Stearic acid, Oleic acid, Linoleic acid and Myristic acid.
According to the Iranian traditional medicine coconut meat is warm and dry and coconut milk is slightly warm and humid. Traditionally coconut was used to treat liver, bladder, bloody diarrhea, kidney stone, gastric and intestinal worms, fever and etc. Also it is helpful in digestive system enhancement.
In Brazil, the extract of fiber of coconut skin is used to treat diarrhea. In Fuji, coconut oil is used to prevent hair loss and coconut juice is used to treat kidney diseases. In Guatemala the extract of fiber of coconut skin is used to reduce kidney inflammation and its ointment is used to treat skin wounds and aging. In Jamaica, the extract of fiber of coconut skin is used for treating diabetes. In Mozambique men use coconut fruit to enhance sexual power. In villages of Malaysia, boiled coconut meat is used to treat fever and malaria.