Coconut Oil Controversy: Updates in Research By Ginger Hultin, MS, RDN, CSO Suggested CDR Learning Codes: 2010, 2020, 3100; Level 2 Suggested CDR Performance Indicators: 8.1.2, 8.3.6 Clients are increasingly interested in the potential health benefits of coconut dietary products. They want to know if these foods are safe to include in their diets and whether they will aid in weight loss or detoxification. Adding to the confusion is the fact that conclusions from research on coconut oil, medium-chain triglycerides (MCTs), and medium-chain fatty acids (MCFAs)—all different products—are often grouped together incorrectly. Conclusions from research on dietary fats has changed through time, raising the question of whether plant saturated fats can be compared fairly with animal saturated fats in regard to health.1,2 With a controversial and complex topic such as coconut, it’s necessary to turn to current human research to separate fact from fiction and speak to clients about coconut with confidence. This continuing education course discusses the different forms of dietary coconut and their unique biochemical composition and digestion. It also addresses health claims for coconut products based on recent human studies so RDNs can help their clients decide whether these products are appropriate to add to the diet. Of the palm or Arecaceae family, coconut (Cocos nucifera) and its edible oils were traditionally used in Asian cultures where these plants grow naturally in tropical environments, namely the Philippines, Indonesia, and India.3 There is also ethnomedicinal evidence that indigenous communities in Mexico used coconut to treat a variety of ailments.4 Coconut products are a staple of Ayurvedic medicine and Indian folk medicine and are used to treat hair loss, burns, and cardiovascular issues. The healing use of coconut was recorded in Sanskrit 4,000 years ago.3,5 Dietary coconut became popular in the United States in the 1950s as medical treatment for malabsorption issues, cystic fibrosis, postsurgical liquid diets, renal disease, and epilepsy.6-

8 It gained popularity in the 1970s and beyond in the American diet as an additive in foods.7 Some tout coconut oil as a miraculous product that heals many ailments and detoxifies the system; cardiothoracic surgeon and television personality Dr. Mehmet Oz, alternative medicine proponent and Web entrepreneur Joseph Mercola, and others claim coconut oil is a cure-all.9,10 This type of attention to coconut products has piqued the interest of consumers who want to know if it can benefit their health. Coconut oil contains 92% saturated fat, a higher percentage than that in beef or butter. It also contains more MCTs compared with other types of dietary fats. For example, soybean oil is composed of 100% long-chain triclycerides (LCTs) while coconut oil in comparison is 60% to 70% MCTs and 30% to 40% LCTs. MCTs are also found naturally in breast milk and in small amounts in full-fat dairy products. Fatty acid lauric acid represents a large portion of the fat content in coconut oil and has been shown in some studies to exhibit antimicrobial properties

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as it destroys lipid-coated bacteria through disintegration of their cell membranes.3 MCTs are digested and absorbed differently than LCTs. The unique properties of coconut oil set it apart from other types of dietary fats. Coconut Product Terminology Copra/Copra Oil Coconut meat is referred to as copra, or kernel. Dried copra holds about 60% to 65% of the oil in a coconut. Copra can undergo a variety of processing methods to extract oil, include refining, bleaching, and deodorizing, to produce a pure, white product. A variety of grades are created, including refined, deodorized, white oil, and industrial, which is not edible without further processing.11,12 Coconut Oil Obtained through processing coconut copra (dry coconut meat) or milk, coconut oil does not contain the fiber compounds found in coconut meat. It’s composed of roughly 90% saturated fatty acids, 60% to 70% of which are made of MCFAs. Coconut oil is refined when made from copra, unrefined when extracted from wet coconut or coconut milk, or refined by solvent extraction.5,11,12 Coconut Water The liquid endosperm, or tissue surrounding the seed to provide nutrition, is a source of B vitamins; vitamin C; enzymes; electrolytes including potassium, sodium, calcium, magnesium, and phosphorus; and sugars and sugar alcohols.3 MCTs MCTs are dietary fats containing solely MCFAs. MCTs are a class of lipids composed of three saturated fats bound to a glycerol backbone but are six to 12 carbons in length rather than the 12 to 22 in LCTs. During digestion, MCTs are rapidly broken down into MCFAs.7,13 MCFAs MCFAs are the products of digestion after the glycerol backbone of MCT has been separated. MCFAs include lauric, caproic, caprylic, and capric acids which are rapidly oxidized in the liver.14 MCFAs are found in small amounts in cow and human breast milk at 1% to 3% total fatty acid composition.7,12,13 MCT Oil Though coconut products contain MCTs, pure MCT oil is extracted from coconut oil to create a product devoid of LCTs. In order to extract pure MCT oil, coconut and palm kernel oils are broken down to remove fatty acids from their glycerol backbone through separation of compounds at high temperatures. The oil is deodorized to create the odorless, colorless, flavorless oil you will find bottled in stores.12 Because of this processing, MCT oil has a low smoke point at 284° F.7

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Virgin Coconut Oil Virgin coconut oil (VCO) can be processed from fresh coconut meat, coconut milk, or coconut milk residue through mechanical or natural means and is done without high heat processing. Studies have shown a higher phenolic content in VCO than through heat processed or refined coconut oil.11,15,16 Mixed tocopherols have also been observed in VCO.16 Studies have also shown VCO to contain among the highest levels of MCFA content at 85% or more, the predominant being lauric acid at roughly 47% of the total content.16,17 For the purpose of this article, the term coconut oil will be used when referring to either wet or dry processing including VCO unless otherwise noted. Coconut oil contains a mixture of MCTs and LCTs. Some studies mention MCFAs or MCT oil specifically which will be noted clearly in the text. Nutrition Composition and Digestion Coconut oil has a unique fatty acid composition with approximately 90% saturated fat in the form of triglycerides, 60% to 70% of which are made of MCFAs. At 46% to 49% lauric acid, coconut oil is nature’s richest source of this fatty acid. Other fats contained include myristic acid, caprylic acid, palmitic acid, capric acid, oleic acid, stearic acid, and linoleic acid.12,18 Culinary uses for coconut oil abound because of its stability, long shelf life, and melting point at 76° F. A nondairy product, it is often used in place of butter for cooking or baked goods because of these unique qualities. LCTs make up the majority of dietary fats, about 95% of the dietary fat we consume.12 During digestion of LCTs, fatty acid chains are separated from their glycerol backbone via the lipase enzyme. The fatty acids are absorbed into lipid molecules called micelles with the assistance of bile salts and phospholipids that transport monoglycerides and fatty acids to the surface of intestinal cells, where they can be absorbed. Inside the intestinal cell, monoglycerides and fatty acids are resynthesized into triacylglycerides, which are packaged into chylomicrons, the transporters of dietary lipids, for liberation from the intestines so they can travel through the lymphatic system and into the bloodstream. Chylomicrons enter the lymphatic system through lacteals, or lypmphatic capillaries, where they eventually enter general circulation in large chest veins. LCT must be transported into the mitochondria of cells via the carnitine shuttle, the gateway through the inner mitochondrial membrane, to gain access to the enzymes of ß-oxidation, a process that provides more than 9 kcal/g.12,17,18 In comparison, up to 30% of MCTs are hydrolyzed to fatty acids and glycerol directly by pancreatic lipase and absorbed directly through the intestinal barrier. These fatty acids are then sent to the liver through the portal vein and attached to albumin for rapid metabolism.2 Even in times of reduced pancreatic secretion, MCFAs can be absorbed and digested, making them an ideal source of fat calories for those with pancreatic insufficiency.7 MCTs do not participate in the biosynthesis and transportation of cholesterol as do LCTs and they are metabolized without the use of the carnitine transport system to cross the mitochondrial membrane of hepatocytes. Rather, MCFAs enter the mitochondria directly and undergo ß-oxidation to ketones. Oxidized MCTs provide fewer calories than LCTs at just over 8 kcal/g.3,6,7,12

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Health Claims and Update on Research Human studies on the potential benefits of coconut oil continue to shed light on the way this uniquely metabolized fat plays a role in health, from obesity and cardiovascular disease (CVD) to neurovascular effects and even detoxification, though studies remain mixed. Obesity Coconut oil is touted as a functional food due to its many health-related properties and nutritional value. There’s much interest in the role of coconut oil and MCTs in weight management and reduction of obesity. Researchers state that LCTs are well established as being lipogenic while MCTs are considered a neutral energy source because MCFAs are easily oxidized and not stored in adipose tissue as long-chain fatty acids are.17,18,19 Studies have suggested that oxygen consumption of humans and animals fed MCTs is higher than that of those fed LCTs, indicating postprandial thermogenesis, which may contribute to the weight reduction effects of coconut oils.13,20 Research suggests that the unique metabolism of MCTs with absorption directly through the portal vein contributes to increased diet-induced thermogenesis as the liver generates up to 30% of the basal metabolic rate.7,8,20,21 Diet-induced thermogenesis with coconut oil consumption has been demonstrated in many small human studies. For example, a small, double-blind, placebo-controlled, crossover study found that although resting energy expenditure was similar before ingestion of either a liquid meal containing 10 g of MCT oil, 5 g of MCT oil plus 5 g of LCT oil, or 10 g of LCT oil, after the six-hour measurement period increases in oxygen consumption were greater in both groups containing MCTs than in those with only LCTs.21 Diet-induced thermogenesis was also observed in a 2007 study in which a single dose of 5 g to 10 g of MCTs increased energy consumption more effectively than did LCT intake.8 This study suggests that even the low dose of 2 g of MCFAs may be suggested daily for improving lipid metabolism in people with a BMI greater than 23.8 Another small, double-blind crossover study found that a liquid meal including 14 g of MCTs plus LCTs yielded a 2.7% increased energy expenditure in proportion to energy intake compared with the same amount of pure LCTs, suggesting that ingesting MCTs likely accelerates energy production and perhaps contributes to a lesser accumulation of body fat in humans.21 Research has shown reductions in BMI, waist and hip circumferences, total fat area, body fat mass, and subcutaneous fat in studies comparing coconut oil with LCT-based dietary fats.2,6,22,23 Authors of a 2014 meta-analysis on both animal and human studies through November 2013 state, “Consumption of food rich in MCFA reduces the level of body fat and the CVD/coronary heart disease risk.”2 A 2015 meta-analysis presented in the Journal of the Academy of Nutrition and Dietetics found that the MCT intervention groups in 12 human studies favored a small but statistically significant weight loss of 0.51 kg.18 These authors also saw beneficial changes in waist and hip circumference and reduced body fat when MCTs, rather than LCTs, were used, often in conjunction with a weight-reduction plan including caloric restriction.18 Two similar 2009 double-blind clinical trials by Liu et al and Xue et al both performed on 112 subjects separated into two groups for eight weeks taking 25 g to 30 g/day of either MCT or LCT oils. Researchers found that participants in the MCT group experienced significant decreases in BMI, waist circumference, hip circumference, waist to hip ratio, body fat weight, body fat percentage, total fat area, and subcutaneous fat.6,24 A small open-label

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pilot study conducted in 2011 by Liau et al on VCO specifically found that the ingestion of 30 mL per day in three divided doses significantly reduced waist circumference after one month (p=0.02).17 Other researchers suggest that supplementation with coconut oil does not cause dyslipidemia and may in fact promote reductions in abdominal obesity in women.25 The effect of weight loss and insulin sensitivity in overweight diabetic subjects has also been assessed in relation to coconut oil consumption. A small 2007 study by Han et al found that 18 g/day of MCTs resulted in the largest reduction in body weight in those with a BMI over 25, with lesser results for subjects with a lower BMI. During this study, the MCT intervention group saw statistically significantly lower body weight and waist circumference (p<0.05). Although there was a trend toward lower fasting insulin levels, it was not statistically significant, though decreased insulin resistance insulin markers HOMA-IR and C-peptide were in the MCT intervention group (p<0.05). Total cholesterol and LDL cholesterol (LDL-C) were significantly reduced by day 90 of the study (p<0.05), while subjects taking LCT oil experienced no change.2,22 It should be noted that many of the studies on the effect of coconut oil on cardiovascular risk and obesity in humans are relatively small, with fewer than 100 participants. Firm conclusions are difficult given the variability in research and many of these studies are at high risk of commercial bias and influence.18

Cardiovascular and Lipid Profile Benefits Research on fat and CVD has changed in recent years. A review of studies that included 347,747 subjects with a follow-up period ranging from five to 23 years suggests that dietary saturated fat intake may not be associated with coronary heart disease, stroke, or CVD as it was once thought to be.26 A 2013 review by Lawrence states, “Mechanisms for adverse health effects [of dietary fat] are lacking.”1 Coconut oil is a saturated fat mostly composed of MCTs and has been the subject of much controversy in relation to cardiovascular health and lipid profile. In some studies assessing the effects of dietary fatty acids in blood lipid profiles of human subjects, consumption of MCTs and coconut oil has shown improvements in serum triglycerides, LDL-C, HDL cholesterol (HDL-C), and apolipoproteins (apo) B, C2, C3, and E.6,19,23,27 Other studies, which show no significant benefit from MCT consumption rather than LCTs, also do not identify negative effects. A 2015 meta-analysis concluded that studies show MCTs did not affect cholesterol, LDL, HDL, or triglycerides.18

Studies of varying designs have continually found small but positive blood lipid associations with ingestion of MCTs. An eight-week study with a two-week washout period in which volunteers’ diets were supplemented with soy milk or coconut milk found a significant decrease in LDL-C (p=0.02) and significant increase in HDL-C (p<0.01) in the coconut group.19 The 2009 clinical trial by Liu et al also found that males in the MCT group experienced significant decreases in levels of serum triglycerides, LDL-C, apo B, apo C2, apo C3, and apo E when compared with the LCT group.6 Individuals who participated in a 2003 study testing 14 g of MCFAs in the diet for 12 weeks experienced significant decreases in total cholesterol and LDL when compared with an LCT intervention group.23 A 2009 randomized, double-blind, clinical trial using 25-30 g daily oil comprised of medium and long chain combined triacylglycerols or pure LCTs found that subjects consuming oil with MCTs experienced significantly lower blood levels of CVD markers triglycerides, apo B, apo A2, apo C2 and apo C3 at week eight (P<0.05).24 A small study testing 10 g of MCTs vs LCTs in a pilaf dish found that

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concentrations of serum triglycerides, chylomicrons, chylomicron-triglyceride, remnantlike particle cholesterol, very LDL (VLDL) cholesterol, VLDL triglyceride (all of the above p<0.001), concentrations of serum insulin (p<0.01), and total ketone bodies (p<0.01) were significantly lower in the MCT group than in the LCT group.27 Many studies note the fact that VCO in particular contains antioxidant phenolic compounds that can reduce lipid peroxidation content, provide anti-inflammatory effects, and even aid in preventing CVD through reduction of atherosclerosis.2,5,11,15,16 Researchers who performed a study with diabetic rats hypothesized that the antioxidant capacity likely had a role in regulating cholesterol synthesis by regulating 3-hydroxy-3-methylglutaryl coenzyme A reductase activity because lipid peroxidation in blood was brought down in the intervention groups. This study revealed antidiabetic effects of VCO, including reduction of blood glucose and lipid levels.28 Other promising studies have also indicated that coconut oil consumption decreases circulating plasminogen activator antigen and lipoprotein-a compared with other saturated or unsaturated fats.29 Epidemiologic studies have shown a connection between reduced fibrinolysis and an increased risk of CVD or myocardial infarction when plasma levels are reduced. Further, studies have suggested that lipoprotein may be an independent risk factor for developing coronary artery disease.29 A small crossover study of college women found that coconut oil-based diets decrease postprandial tissue plasminogen activation antigen, favorably affecting plasminogen activation when compared with an unsaturated fat-based diet.29 In this study, fasting serum lipoprotein a concentration was lower in those who consumed the coconut oil diet than in those on the unsaturated fats diet (p<0.0001).29 MCFAs have also shown promise for the prevention and treatment of metabolic syndrome (abdominal obesity, hypertriglyceridemia, low HDL, hypertension, and elevated fasting glucose levels), though these studies almost always replace LCT dietary fats with MCT sources. The replacement rather than the addition appears to be a significant factor.14,18 Neurodegenerative Diseases Previously, a low-fat or Mediterranean diet has been suggested to reduce risk factors for Alzheimer’s disease, including atherosclerosis, elevated blood pressure, and accumulation of fat storage.5,30 Chronic intake of diets high in fat, particularly saturated fat, have been linked to declines in cognitive function including those brought about by Alzheimer’s disease and dementia in both older adult and animal studies, while intake of polyunsaturated and omega-3 fatty acids are associated with decreased risk.31 However, because of the unique composition of saturated fat from coconut including MCT content and antioxidants, research indicates that coconut oil may have potential for preventing cognitive decline and Alzheimer’s disease. Several studies have suggested that coconut oil and coconut milk have potential cognitive benefits.5,11,12 Studies have shown low glucose utilization in Alzheimer’s patients, suggesting that ketone bodies may benefit the brain through enhanced adenosine triphosphate output in the mitochondria.5 Because MCTs are converted into ketones after being metabolized by the liver, dietary coconut has shown some promise for the prevention and treatment of Alzheimer’s disease. MCTs can act as a noncarbohydrate fuel source for the brain by forming ketone bodies. MCT ketogenic diets contain less overall fat than do traditional ketogenic diets, and

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some studies have reported them as being more healthful as they contain more fruits and vegetables.5 The phenolic compounds and hormones including cytokinins are thought to

prevent the aggregation of amyloid-β peptide.5

Considering genetic variants including high-risk APOE4, studies have not shown significant improvement with treatments for mild to moderate Alzheimer’s disease, although a ketogenic diet has shown some promise. Clinical trials have showed that 20 g/day of a product containing MCTs did not significantly improve cognitive function in these patients when compared with the placebo group after 90 days. The study did show that that a subgroup of these patients with the APOE4 gene variant did benefit significantly in cognitive scores compared with those who received a placebo.32 Another preliminary clinical study shows that a single dose of the product containing MCTs improves measures of cognitive function in patients with the APOE4 gene variant, but not in patients without the gene variant.33 The Alzheimer’s Association also states, “Some people with Alzheimer’s and their caregivers have turned to coconut oil as a less expensive, over-the-counter source of caprylic acid. A few people have reported that coconut oil helped the person with Alzheimer’s, but there’s never been any clinical testing of coconut oil for Alzheimer’s, and there’s no scientific evidence that it helps.”34

Research on the benefit of coconut oil or MCT oil in the prevention and treatment of cognitive decline is yet inconclusive though it appears that consuming these types of fats in a well-rounded diet may not be harmful and may offer future potential for cognitive benefit. Malabsorption Before coconut oil was studied for weight management, for cognitive benefit, or to improve lipid profiles, it was used in the 1950s in the United States in clinical nutrition for the management of malabsorption syndromes. Coconut oil was valuable to patients in this population because it is rapidly absorbed and soluble. MCTs are hydrolyzed, absorbed, and utilized by the body in a different way than are LCTs.27 MCTs are used as adjunctive therapy and in parenteral nutrition for diarrhea, steatorrhea, postgastrectomy, lymphatic abnormalities, celiac disease, hepatic disease, and intestinal resection or short bowel syndrome.7,35 The rapid absorption and solubility of MCTs make them an ideal energy source postsurgery or for those who may have difficulty digesting and assimilating LCTs in dietary fat sources. Antibacterial, Antiviral, Antimicrobial Properties Because of the predominant lauric acid content of coconut oil at 45% to 50% MCTs, it has antimicrobial effects and can disrupt the lipid membrane of bacteria and viruses.3,36,37 A 2013 study on Clostridium difficile in the hospital setting found that the lauric, capric, and caprylic acids in VCO inhibited C diff growth (p<0.001). In this study VCO itself was not used; rather lipolyzed coconut oil was used, which caused changes in the bacterial cell membrane.38 A 2010 study on the antimicrobial properties of coconut oil applied to the skin found that coconut oil creams exhibited antibacterial and antifungal properties.36 This study cites an older study from the 1990s that found coconut oil killed the HIV, herpes, and gonococci viruses within one minute of direct application. There is evidence of coconut oil’s use in folk medicine, particularly as a skin antiseptic that supports wound healing from cultures around the world.4

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Detox Oil pulling has become a popular method of systemic detoxification. An Ayurvedic practice, swishing oil in the mouth and then spitting it out has been used in traditional Indian folk medicine to prevent a variety of oral diseases and was also said to cure systemic problems such as diabetes.39 Traditionally, unsaturated fats such as sesame or sunflower oil were used. Despite this practice’s growing popularity, there is limited scientific evidence of these claims. There have been small studies done on this topic, mainly including people with significant oral disease such as gingivitis. In one 2009 study, adolescent boys who oil pulled for 10 days with either sesame oil or the antiseptic chlorhexidine had equal reduction of plaque and gingival index (p<0.001).40 A study done on school-aged children with gingivitis found that coconut oil pulling for 30 days significantly decreased plaque and gingival incidence after day seven.37 It is hypothesized that oil pulling works either through mechanical force and emulsification of plaque or by forming a film on the surface of teeth that reduces plaque adhesion and bacterial aggregation in the area.37 Because of lauric acid’s antibacterial effects, coconut oil may be especially helpful for periodontal disease. For individuals suffering from gingivitis or other oral disease, swishing a variety of oils, including sesame or coconut or an antiseptic, may be useful as an adjuvant treatment.37 More research is needed to understand if oil pulling can help detoxification on a more systemic level. Other Considerations Coconut oil can be environmentally friendly. In the Philippines, it’s used as biodiesel.3 There are many nonedible applications for coconut oil, a natural product that has many uses. Studies have shown coconut oil to be an efficient and safe skin moisturizer or lotion due to its antiseptic effects, and it’s also been used in folk medicine for topical wound healing.4 Putting It Into Practice It’s important to keep in mind that much of the current research on coconut oil and MCTs is based on animal models or small human studies. There’s evidence that coconut oil and MCTs may be helpful for specific disease states due to the unique digestion and absorption of these fatty acids. There’s also evidence that coconut oil may be useful for weight management, prevention of CVD, prevention and treatment of Alzheimer’s disease, and for those with malabsorptive issues. In human weight management studies, both control and intervention groups often saw positive changes, but they were also most often consuming a calorie-controlled diet and including physical activity; studies are not showing that simply adding coconut oil in addition to one’s current diet is helpful. Research indicates that replacing LCT dietary fats with MCTs in addition to a generally healthful diet and physical activity may show some positive outcomes. Researchers suggest that diets rich in MCFAs appear to be safe and well tolerated in both short and long-term studies.14 Coconut oil is trending strongly, and clients should be advised that dietary coconut oil appears to be safe and provide some potential health benefits, though more research is warranted. High doses of coconut oil have not been shown to detoxify or offer miracle health benefits. Rather, coconut oil may support weight management and a healthy lipid profile when consumed with an appropriate caloric intake in individuals with physically active lifestyles and in place of dietary LCT fat sources. VCO may be a healthier choice than more processed and

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refined coconut oil because it has a higher MCT and phenolic content and is subject to less chemical or heat processing. Dietitians can suggest minimally processed coconut products to be incorporated into a healthy diet. — Ginger Hultin, MS, RDN, CSO, is a nutrition and health writer and integrative oncology specialist. Hultin is chair-elect of the Vegetarian Nutrition Dietetic Practice Group, immediate past president of the Chicago Academy of Nutrition and Dietetics, and media representative for Chicago through the Illinois Academy of Nutrition and Dietetics. She blogs at champagnenutrition.com. References 1. Lawrence GD. Dietary fats and health: dietary recommendations in the context of scientific evidence. Adv Nutr. 2013;4(3):294-302. 2. Babu AS, Veluswamy SK, Arena R, Guazzi M, Lavie C. Virgin coconut oil and its potential cardioprotective effects. Postgrad Med. 2014;126(7):76-83. 3. DebMandal M, Mandal S. Coconut (Cocos nucifera L.: Arecaceae): in health promotion and disease prevention. Asian Pac J Trop Med. 2011;4(3):241-247. 4. Sosnowska J, Balslev H. American Palm Ethnomedicine: a meta-analysis. J Ethnobio Ethnomed. 2009;5:43. 4. Fernanado WM, Martins IJ, Goozee KG, Brennan CS, Jayasena V, Martins RN. The role of dietary coconut for the prevention and treatment of Alzheimer’s disease: potential mechanisms of action. Brit J Nutr. 2015;114(1):1-14. 6. Liu Y, Wang J, Zhang R, et al. A good response to oil with medium- and long-chain fatty acids in body fat and blood lipid profiles of male hypertriglyceridemic subjects. Asia Pac J Clin Nutr. 2009;18(3):351-358. 7. Takeuchi H, Sekine S, Kojima K, Aoyama T. The application of medium-chain fatty acids: edible oil with a suppressing effect on body fat accumulation. Asia Pac J Clin Nutr. 2008;17(Suppl 1):320-323. 8. Aoyama T, Nosaka N, Kasai M. Research on the nutritional characteristics of medium-chain fatty acids. J Med Invest. 2007;54(3-4):385-388. 9. 99 amazing uses for coconut oil. The Dr. Oz Show website. http://www.doctoroz.com/gallery/99-amazing-uses-coconut-oil?gallery=true&page=12. Published February 23, 2015. Accessed September 11, 2015.

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10. Coconut oil: this cooking oil is a powerful virus-destroyer and antibiotic. Mercola website. http://articles.mercola.com/sites/articles/archive/2010/10/22/coconut-oil-and-saturated-fats-can-make-you-healthy.aspx. Published October 22, 2010. Accessed January 6, 2016. 11. Marina AM, Che Man YB, Amin I. Virgin coconut oil: emerging functional food oil. Trends Food Sci Technol. 2009;20(10):481-487. 12. Krishna GA, Raj G, Bhatnagar AS, Kumar PPK, Chandrashekar P. Coconut oil: chemistry, production and its applications — a review. Indian Coconut J. 2010;73(3):15-27. 13. St-Onge MP, Jones PJ. Physiological effects of medium-chain triglycerides: potential agents in the prevention of obesity. J Nutr. 2002;132(3):329-332. 14. Nagao K, Yanagita T. Medium-chain fatty acids: functional lipids for the prevention and treatment of the metabolic syndrome. Pharmacol Res. 2010;61(3):208-212. 15. Vysakh A, Ratheesh M, Rajmohanan TP, et al. Polyphenolics isolated from virgin coconut oil inhibits adjuvant induced arthritis in rats through antioxidant and anti-inflammatory action. Int Immunopharmacol. 2014;20(1):124-130. 16. Mansor TST, Che Man YB, Shuhaimi M, Abdul Afiq MJ, Ku Nurul FKM. Physicochemical properties of virgin coconut oil extracted from different processing methods. Int Food Res J. 2012;19(3):837-845. 17. Liau KM, Lee YY, Chen CK, Rasool AH. An open-label pilot study to assess the efficacy and safety of virgin coconut oil in reducing visceral adiposity. ISRN Pharmacol. 2011;2011:949686. 18. Mumme K, Stonehouse W. Effects of medium-chain triglycerides on weight loss and body composition: a meta-analysis of randomized controlled trials. J Acad Nutr Diet. 2015;115(2):249-263. 19. Ekanayaka RAI, Ekanayaka NK, Perera B, De Silva PGSM. Impact of a traditional dietary supplement with coconut milk and soya milk on the lipid profile in normal free living subjects. J Nutr Metab. 2013;2013:481068. 20. Kasai M, Nosaka N, Maki H, et al. Comparison of diet-induced thermogenesis of foods containing medium- versus long-chain triacylglycerols. J Nutr Sci Vitaminol (Tokyo). 2002;48(6):536-540. 21. Ogawa A, Nosaka N, Kasai M, et al. Dietary medium- and long-chain triacylglycerols accelerate diet-induced thermogenesis in humans. J Oleo Sci. 2007;56(6):283-287. 22. Han JR, Deng B, Sun J, et al. Effects of dietary medium-chain triglyceride on weight loss and insulin sensitivity in a group of moderately overweight free-living type 2 diabetic Chinese subjects. Metabolism. 2007;56(7):985-991.

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23. Kasai M, Nosaka N, Maki H, et al. Effect of dietary medium-and long-chain triacylglycerols (MLCT) on accumulation of body fat in healthy humans. Asia Pac J Clin Nutr. 2003;12(2):151-160. 24. Xue C, Liu Y, Wang J, et al. Consumption of medium- and long-chain triacylglyercols decreases body fat and blood triglyceride in Chinese hypertriglyceridemic subjects. Eur J Clin Nutr. 2009;63(7):879-886. 25. Assunção ML, Ferreira HS, dos Santos AF, Cabral CR Jr, Florêncio TM. Effects of dietary coconut oil on the biochemical and anthropometric profiles of women presenting abdominal obesity. Lipids. 2009;44(7):593-601. 26. Siri-Tarino PW, Sun Q, Hu FB, Krauss RM. Meta-analysis of prospective cohort studies evaluating the association of saturated fat with cardiovascular disease. Am J Clin Nutr. 2010;91(3):535-546. 27. Kasai M, Maki H, Suzuki Y, et al. Effect of medium-chain triglycerides on postprandial concentrations of remnant-like particles in healthy men. J Oleo Sci. 2003;52(4):197-204. 28. Siddalingaswamy M, Rayaorth A, Khanum F. Anti-diabetic effects of cold and hot extracted virgin coconut oil. J Diabetes Mellitus. 2011;1(4):118-123. 29. Müller H, Lindman AS, Blomfeldt A, Seljeflot I, Pedersen JI. A diet rich in coconut oil reduces diurnal postprandial variations in circulating tissue plasminogen activator antigen and fasting lipoprotein (a) compared with a diet rich in unsaturated fat in women. J Nutr. 2003;133(11):3422-3427. 30. Gu Y, Luchsinger JA, Stern Y, Scarmeas N. Mediterranean diet, inflammatory and metabolic biomarkers, and risk of Alzheimer’s disease. J Alzheimers Dis. 2010;22:483-492. 31. Walker JM, Harrison FE. Shared neuropathological characteristics of obesity, type 2 diabetes and Alzheimer’s disease: impacts on cognitive decline. Nutrients. 2015;7(9):7332-7357. 32. Henderson ST, Vogel JL, Barr LJ, Garvin F, Jones JJ, Costantini LC. Study of the ketogenic agent AC-1202 in mild to moderate Alzheimer’s disease: a randomized, double-blind, placebo-controlled, multicenter trial. Nutr Metab (London). 2009;6:31. 33. Reger MA, Henderson ST, Hale C, et al. Effects of beta-hydroxybutyrate on cognition in memory-impaired adults. Neurobiol Aging. 2004;25(3):311-314. 34. Alternative treatments. Alzheimer’s Association website. http://www.alz.org/alzheimers_disease_alternative_treatments.asp. Accessed March 5, 2016.

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35. Coconut oil. Natural Medicines Database website. http://naturaldatabase.therapeuticresearch.com/nd/Search.aspx?pt=100&id=1092. Updated January 26, 2016. 36. Oyi AR. Formulation and antimicrobial studies of coconut (Cocos nucifera linne) oil. Res J Appl Sci Eng Technol. 2010;2(2):133-137. 37. Peedikayil FC, Sreenivasan P, Narayanan A. Effect of coconut oil in plaque related gingivitis — a preliminary report. Niger Med J. 2015;56(2):143-147. 38. Shilling M, Matt L, Rubin E, et al. Antimocrobal effects of virgin coconut oil and its medium-chain fatty acids on Clostridium difficile. J Med Food. 2013;16(12):1079-1085. 39. Singh A, Purohit B. Tooth brushing, oil pulling and tissue regeneration: a review of holistic approaches to oral health. J Ayurveda Integr Med. 2011;2(2):64-68. 40. Asokan S, Emmadi P, Chamundeswari R. Effect of oil pulling on plaque induced gingivitis: a randomized, controlled, triple-blind study. Indian J Dent Res. 2009;20(1):47-51.

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Quiz 1. Coconut oil is nature’s richest source of which fatty acid? A. Caprylic acid B. Lauric acid C. Linoleic acid D. Caproic acid 2. Coconut and medium-chain triglyceride (MCT) oils first became popular for medical use in the United States in which decade? A. 1920s B. 1950s C. 1970s D. 1990s 3. According to material presented in this course, how many kcal/g does oxidation of MCTs yield vs long-chain triglycerides (LCTs)? A. 8 vs 9 B. They are equal at 9 C. 10 vs 8 D. 6 vs 7 4. How much fat do MCT ketogenic diets contain compared with regular ketogenic diets? A. The same amount B. More C. Less D. A comparison cannot be drawn 5. Why has increased diet-induced thermogenesis been observed in human studies with the consumption of coconut oil? A. Coconut oil has fewer calories than other types of fat. B. Coconut oil has more calories than other types of fat. C. MCTs undergo special processing as they pass through the hepatic portal vein. D. MCTs are absorbed directly into the liver, which contributes to 30% of the basal metabolic rate. 6. Studies have shown a strong correlation between dietary coconut oil consumption and reduced inflammatory markers. A. True B. False

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7. According to material presented in this course, which of the following is a reason that consuming coconut oil aids in weight management? A. The lauric acid content blocks the accumulation of fat cells in humans. B. Oxygen consumption by humans and animals fed MCTs is much lower than that of those who consume LCTs. C. The unique portal vein metabolism does not contribute to diet induced thermogenesis. D. The ingestion of MCTs accelerates energy production. 8. The potential cognitive benefits of coconut oil and/or MCT consumption may be attributed to which of the following? A. Lauric acid content B. A high antioxidant level present in coconut products C. Ketone bodies being used as fuel by the brain D. The unique metabolism of MCTs through the hepatic portal vein 9. Which of the following characterizes oil pulling? A. It has been shown beneficial for those with periodontal disease. B. Compelling studies suggest it detoxifies the body. C. It has no use in detox or oral hygiene. D. It has proven useful for detoxification but only in animal studies. 10. Which of the following is true about research on coconut oil and dietary coconut for human health? A. It’s well documented and conclusive. B. It’s skewed by the bias of media outlets. C. It’s based on small human and animal studies but shows potential health benefits. D. Research is not thorough enough to make any recommendations at this time.