Coconut is both very healthy and very high in saturated fat. That might sound like a paradox, but the saturated fats in coconut are physically shorter than the saturated fats in animal products, which changes everything. In a meta-analysis of all the published research (60 qualified studies) on how the different types of saturated fats affect human health [1], it was shown that (relative to carbohydrate) the specific type of saturated fat in coconut lowers the total cholesterol / HDL ratio as much or more than both monounsaturated and polyunsaturated fats. Although coconut fat raises total cholesterol more than other types of saturated fat, so much of the increase is from higher levels of HDL (the “good” cholesterol) that the overall effect is beneficial. This is supported by a recent review of the epidemiological literature [2] showing that people who eat the most coconut (in Sri Lanka, Tokelau in Polynesia, and Biolanos in the Philippines) have less coronary heart disease than in regions immediately around them or in Western countries where animal fats have given saturated fats a bad name. Two other studies done in Minangkabau, Indonesia [3] and Kerala in southern India [4] where coconut consumption is very high have shown that coconut is not correlated to heart disease in either location, whereas eating animal fats is correlated to heart disease in Kerala, just as it is throughout the world.
It is easy to get caught up in America’s indictment of coconut because of our bad experience with animal fats. For example, in the September 2006 Harvard Heart Letter, Dr. Walter Willet, one of the most respected nutrition epidemiologists in the world, and who created the Harvard Food Pyramid to counter Western eating patterns, wrote: “coconut and coconut oil can’t be considered heart-healthy foods. A 2-ounce piece of fresh coconut contains more than 13 grams of saturated fat—nearly two-thirds of the recommended daily limit for the average person. Ounce for ounce, coconut oil delivers more saturated fat than butter, lard, or margarine. Feeding studies in humans, monkeys, and rabbits show that coconut oil substantially elevates LDL (bad) cholesterol.” Dr. Willet does, however, put in a good word for adding coconut to unhealthy carbs and alcohol: “Do you need to avoid coconut? No. Fresh coconut is delicious, shredded coconut livens up pastries and granola, and who can resist a spicy coconut curry, or a piña colada at a beach party? But to take the best care of your heart and blood vessels, think of these as treats rather than as everyday choices.” In other words, if you aren’t avoiding pastries and beach-party alcohol, you might as well go for the gusto and not avoid coconut either. But don’t enjoy it too much, because you are headed towards a heart attack. The message is to moderate coconut the same way you do junk food.
I have tremendous respect for Walter Willet’s work, so I wanted to find out the scientific facts on coconut to help me sort out my confusion once and for all. I reviewed all of the published scientific studies with the word “coconut” in the title listed in the National Institutes of Health scientific library (Pubmed) going back to 1919. Of the 561 scientific papers published to date, there are 40 relevant to coconut consumption and health. These show the following:
· Fish oil is healthier than coconut, but no study has shown coconut to raise the total cholesterol or LDL / HDL ratio in any species (see also the next bullet point). Coconut is significantly healthier than butter and, relative to vegetable oils, coconut reduces the two worst things about LDL cholesterol: LDL oxidation (because saturated fat is not easily oxidized) and total VLDL production (very low density lipoprotein). [5-22]
· The worst results I could find with respect to heart disease and coconut consumption is that coconut has a “neutral effect on serum cholesterol” in humans [23], that although coconut reduces plaque buildup in the aortic arch it stabilizes out at a higher plaque level in the ascending aorta compared to olive oil in hamsters [24], and in one study with monkeys the total cholesterol / HDL ratio was a bit higher but this was not statistically significant [25].
· Coconut generally increases mitochondria function (fat burning), in part because the saturated fats in coconut (being shorter than saturated fats in animals) are burned directly as fuel rather than primarily being put into storage first. [26-32]
· Coconut lowers blood-clotting activity [33, 34]
· Coconut contains antifungal compounds [35, 36]
· Coconut reduces colon cancer, breast cancer (more than fish oil), and tumor necrosis factor (more than corn oil) in mice [37-39]
· Coconut
helps protect the kidneys against injury [40]
Clyde’s Thoughts: I am not surprised about the confusion on coconut. It took me 2 full days of work to carefully review all of the literature. I have wanted to do this for over a year and could never find the time, so I don’t blame anyone for giving advice against coconut before doing the work necessary to find out all the facts. It is much easier to just base one’s opinion on a few papers or on general consensus. But ultimately we need to know all the facts before we start placing restrictions on our lives or what we eat. And here are the facts: Coconut lowers the total cholesterol / HDL ratio, plaque development, blood clotting, and cancer, and raises fat burning, resistance against microbes, kidney protection, and (as shown in the population studies) raises cardiovascular health. Not only can’t I find a single study that shows coconut to be harmful to health, but when you look at the entire body of scientific results as a whole, one might conclude that coconut should be consumed frequently…maybe even every day, and in amounts equivalent to olive oil and fish. I view our anxiety of coconut because of its saturated fat content as being similar to the Salem witch-hunts. Just because a person or food has some quality that gives us concern doesn’t mean we should eliminate them or it without taking the time to ask some objective questions first.
Clyde’s Advice: Fats are high in calories, which is why I recommend any of the following per meal; 1 thumb (1 Tbsp) of olive or vegetable oil or nut butter such as peanut butter, 2 thumbs of coconut or nuts or olives, 3 thumbs of seeds such as sunflower seeds, or 4 thumbs of avocado. These are all extremely healthy fats and should be in as many of your meals as possible. It doesn’t matter which one you choose to eat as far as healthy goes, so eat the ones you like the most. In other words, eat coconut the same way you would vegetable oils, nuts or fish. Just keep in mind, with any of these foods, that because fats are high in calories, you eat them in the amounts of “thumbs” rather than half fists (protein, starches, and fruit) or double fists (vegetables). So if you like coconut, eat 2 thumbs worth (1.5 x 2 inch piece), which is 1 oz (28 g), or 100-120 Calories worth in any meal. I would not go over two times this amount just from a calorie perspective. You can always eat more at your next meal.
I do not know how shredded coconut is processed or how long it is stored before it is consumed, so I do not know if it contains rancid fats. I don’t have any evidence either way. But fresh coconut would be expected to have the peak health value over and above any products produced from it, i.e. the food industry does not improve the health value of foods with processing and storage. I use dried coconut the same way I would use dried fruit; as part of a snack I am eating while on the go. But I eat fresh at home (I buy one almost every week). I use coconut milk in recipes. Note that most of the regions in the world where people eat a lot of coconut fat and are healthier for it are consuming products like canned coconut milk and coconut oil.
The Bottom Line: Coconut is a health food, and might even be a sports food because its fats are so easily burned by the body. For a great meal containing coconut, see December’s Dr. Clyde Recipe of the Month by Chef Andrea.
References:
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2. “Coconut oil: Atherogenic
or not?”, Dayrit CS, Philippine J Cardiology 31 2003 97
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4. “Dietary intake and the
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Sumatra, Indonesia”, Lipoeto NI et al., Asia Pac J Clin Nutr 13 2004 377
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DMBA”, Craig-Schmidt M et al., Nutr Cancer 20 1993 99
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oil”, Bibby DC and Grimble RF, Clin Sci (London) 79 1990 657
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coconut oil on renal necrosis occurring in rats fed a methyl-deficient diet”,
Monserrat AJ et al., Ren Fail 17 1995 525
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