The nutritionists and professors responsible for designing dietary guidelines for the public are not fond of saturated fat. They have long argued that it is healthier to limit consumption of cheese, butter, ghee, bacon, sausages, and other foods high in saturated fatty-acids. A large body of scientific evidence concurs.
One problem with such a general recommendation, however, is that coconuts have been included in the same category as the aforementioned foods. Coconuts are indeed rich in saturated fat; however, their fatty-acid profile differs markedly from those of high-fat dairy foods and processed, fatty meats. Whereas the latter foods are high in long-chain saturated fatty-acids, coconuts contain primarily lauric acid, a short-chain fatty acid. Moreover, unlike animal-source foods, coconuts are rich in fiber. This helps explain the different metabolic and physiological impacts of coconut consumption compared to those of high-fat animal-product consumption.
The Devil Is in the Details
In recent decades, a number of researchers have examined the effects of saturated-fat intake on blood-lipid profile and general health. The key takeaway from these studies and meta-analyses is, in general, an argument against high saturated-fat consumption. This is not favorable news to Atkins devotees and other low-carbers who rely on butter as a primary source of energy; however, it is arguably the truth. It’s also the reason why public-health authorities are hesitant to change their stance on saturated fat.
That said, saturated fat is a natural part of a healthy diet. It’s impossible to completely avoid it, unless one exclusively eats low-fat plant foods. Moreover, not all saturated fatty acids are equally detrimental to our blood-lipid profile and general health.
Simply scanning over the abstracts or conclusions of the studies on saturated fat may obscure such a point. In order to catch this important detail, we must take a closer look at the science, as well as consider the roles that different fatty-acids play in nature and in the human diet.
Differential Effects on Cholesterol Levels
In 2003, a comprehensive meta-analysis found that the ratio of total-to-HDL cholesterol decreased when saturated fatty acids were replaced by cis unsaturated fatty acids.
This doesn’t automatically impugn saturated fatty-acids as “bad”; however, it should cause us to think twice before incorporating a lot of saturated fats into our diets, given that the ratio of total-to-HDL cholesterol is a well-established marker of cardiovascular-disease risk.
What’s particularly interesting about this meta-analysis is that it didn’t lump all saturated fatty acids together. The researchers took the time to investigate how different types of saturated fatty acids affect our cholesterol levels. They found that lauric acid greatly increases total cholesterol; however, much of its effect was shown to be on HDL cholesterol, the “good” cholesterol. Lauric acid was actually found to have the most favorable effect on total-to-HDL cholesterol ratios of all fatty acids, both saturated and unsaturated.
This meta-analysis had several limitations and some of its results conflicted with those of other studies; however, it’s still interesting and relevant, particularly considering that the coconut is the darling of the evolutionary-health community. Its results, in combination with other studies linking the consumption of coconut products with several positive health outcomes, clearly indicate that lauric acid has some uniquely beneficial properties.
The Unique Properties of Lauric Acid
Medium-chain fatty acids are digested and metabolized in a more direct manner than long-chain fatty acids. They don’t require the usual degradation or re-esterification processes, absorb rapidly into the body, and may be less obesogenic and inflammatory than long-chain saturated fatty acids. Moreover, these particular fatty acids may exert uniquely favorable effects upon helpful gut microbial populations .
Whereas long-chain saturated fatty acids appear to be neutral (and in some instances even encouraging) toward certain types of proinflammatory gut bacteria, short- and medium-chain fatty acids, including lauric acid, appear to inhibit the growth of several problematic gut bugs.Indeed, long-chain saturated fatty acids such as palmitic acid, the dominant fatty acid found in cheese, butter, and fatty livestock meats, have been linked with dysbiosis, intestinal-barrier impairment, and metabolic endotoxemia; certain shorter-chain fatty acids have been found to protect against these conditions.
Well-known for possessing antimicrobial properties, lauric acid is helpful for inhibiting the growth of some problematic skin and gut microbes. Coconut products such as monolaurin, a substance formed from combining glycerol and lauric acid from coconut oil, have long been used to treat a variety of bodily infections, with varying degrees of success.
Coconut-heavy Diets in Traditional Cultures
Coconuts’ abundant lauric acid (about 50% of the total fat in coconut oil) and paucity of long-chain saturated fatty acids help explain why traditional, coconut-loving cultures such as the Kitavans enjoy such superb health. They don’t suffer from cardiovascular disease or other disorders that have been associated with an unfavorable lipid profile.
Notably, though, the Kitavans don’t eat spoonfuls of coconut oil every day; rather, they eat primarily unprocessed (or minimally processed) coconut products. Coconut oil has a very different nutritional composition from coconut meat: no fiber, yet concentrated fat and calories. This doesn’t mean that it can’t be a part of a healthy diet; however, we might think twice before starting to add it to everything we eat.
This is particularly true for people who have “weak stomachs.” Coconut oil is packed with fatty, antimicrobial substances (e.g., lauric acid); hence, it could induce some gastrointestinal upset if consumed in large quantities. It’s unlikely to induce acute diarrhea, but it could cause some looseness of the bowels by altering gut microbiota.
The degree to which coconut products agree with our biology may partly depend on our genetic heritage. People whose ancestors habitually consumed coconuts may perhaps find them more agreeable than people whose fairly recent ancestors lived in non-tropical climes. Coconuts were probably available in some parts of Africa where early humans lived; however, much climatic change (and resultant dietary adaptation) has occurred since Homo sapiens sapiens migrated out of Africa some 50,000-100,000 years ago.
Key Takeaways
The fatty-acid composition of coconuts differs markedly from that of high-fat dairy products and very fatty meats, the two primary sources of saturated fat in the typical western diet. Coconuts are uniquely high in lauric acid, a short-chain saturated fatty acid that confers much more favorable effects on our blood-lipid profiles than those of longer-chain saturated fatty acids like palmitic acid. This helps explain why coconut-reliant, traditional peoples such as the Kitavans are very healthy despite eating a diet fairly high in saturated fat.
References:
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