The nutritionists and professors who are responsible for designing dietary guidelines for the public are not fond of saturated fat. They have long argued that we would all be wise to limit our consumption of cheese, butter, ghee, bacon, sausages, and other foods that are very high in saturated fatty acids. I stand behind this assertion. A large body of scientific evidence does as well.
There’s one thing I take issue with though, and that is that coconuts tend to be lumped into the same category as the aforementioned foods. Coconuts are indeed rich in saturated fat; however, their fatty acid profile differs markedly from that 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 why the metabolic and physiological impact of coconut consumption has been shown to differ from that of the consumption of high-fat foods of animal origin…
The devil is in the detail
Over the most recent decades, a number of researchers have looked into how the intake of saturated fat affects our blood lipid profile and general health. This work has resulted in the publication of a substantial number of scientific papers, some of which are meta-analyses that combine and summarize the results of many experimental studies.
The key takeaway from these studies, as I see it, is that it’s unwise to consume a lot of saturated fat. Some of the trials and meta-analyses that have been conducted to date did not detect a relationship between saturated fat intake and certain health outcomes; however, these studies are few and far between when compared with all of the studies that indicate that diets high in saturated fat don’t do a body good.
This is not something Atkins devotees and low-carbers who rely on butter as a primary source of energy like to hear; however, it is arguably the truth. It’s also the reason why public health authorities are hesitant to change their stance on saturated fat.
With all of that being said, saturated fat is a natural part of a healthy diet. It’s impossible to completely avoid saturated fat, unless one exclusively eats plants foods that are very low in fat. Moreover, it’s important to point out that not all saturated fatty acids are equally problematic with respects to their impact on our blood lipid profile and health.
If one simply scans over the abstracts or conclusions of the studies on saturated fat, this is something one may miss. In order to catch this important detail, one has to take a closer look at the science, as well as consider the role different fatty acids play in nature and in the human diet.
Different types of saturated fatty acids differently affect our cholesterol levels
In 2003, a very comprehensive meta-analysis entitled Effects of dietary fatty acids and carbohydrates on the ratio of serum total to HDL cholesterol and on serum lipids and apolipoproteins: a meta-analysis of 60 controlled trials was published in the American Journal of Clinical Nutrition (1). Like many other similar studies, this 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 lead to the conclusion that saturated fatty acids are “bad”; however, it should cause us to think twice before we bring a lot of saturated lipids into our diet, seeing as 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. Through their analyses they found that lauric acid greatly increases total cholesterol; however, much of the effect was shown to be on HDL cholesterol – the “good” cholesterol. Lauric acid was actually found to have the most favorable effect on total:HDL cholesterol of all fatty acids, both saturated and unsaturated ones.
The meta-analysis has several limitations and some of its results conflict with those of other studies; however, it’s an interesting study nonetheless, particularly considering that the coconut is the darling of the evolutionary health community.
Its results, in combination with the results of various studies that have found a link between the consumption of coconut products and several positive health outcomes, clearly indicate that lauric acid has some unique properties that distinguish it from other fatty acids. What could these properties be…?
Lauric acid, the primary fatty acid in coconut, has some unique properties that separate it from other fatty acids
Medium chain fatty acids are digested and metabolized in a different manner than long-chain fatty acids. They tend not to undergo degradation or re-esterification processes, are absorbed rapidly into the body, and may be less obesogenic and inflammogenic than long-chain saturated fatty acids (2). Moreover, different types of fatty acid differently affect the microbial communities of the human gut (3, 4).
Whereas long-chain saturated fatty acids appear to be inactive against, or in some instances induce the growth of, certain types of proinflammatory gut bacteria, short-chain and medium-chain fatty acids, including lauric acid, appear to inhibit the growth of several problematic gut bugs (3, 4). Hence, it’s not surprising that long-chain saturated fatty acids such as palmitic acid, the dominant type of fatty acid found in cheese, butter, and fatty meats derived from domesticated animals, have been linked with dysbiosis, intestinal barrier impairment, and metabolic endotoxemia, whereas certain shorter-chain fatty acids have been found to protect against these issues (3, 4).
It shouldn’t really come as a surprise that lauric acid is able to inhibit the growth of some gut microbes (3, 5, 6), considering that it’s well-known that it has antimicrobial properties. Coconut products, including monolaurin, a substance formed from a mixture combining glycerol and lauric acid from coconut oil, have long been used to treat a variety of bodily infections, with varying degrees of success.
Many traditional populations have been known to thrive on a coconut-heavy diet
The fact that coconuts are high in lauric acid (about 50% of the total fat in coconut oil) while low in long-chain saturated fatty acids helps explain why traditional people such as the Kitavans, who are known to eat a lot of coconuts, are in superb health. They don’t suffer from cardiovascular disease or other disorders that have been associated with an unfavorable lipid profile.
What’s important to point out though is that the Kitavans don’t ingest spoonfuls of coconut oil every day; rather, they eat primarily minimally processed coconut products. Coconut oil has a very different nutritional composition than coconut meat. Among other things, it doesn’t contain any fiber and is extremely high in fat and energy. This doesn’t mean that it can’t be a part of a healthy diet; however, it should cause us to think twice before we embrace it and start adding it to most everything we eat.
This is particularly true for people who have a “weak stomach”. Coconut oil is packed with fatty, antimicrobial substances (e.g., lauric acid); hence, it could induce some gastrointestinal issues if it’s consumed in large quantities. It’s unlikely to induce acute diarrhea, but it could cause some looseness of the bowels by altering the microbiota of the gut.
The degree to which coconuts, as well as coconut oil, agree with our biology partly depends on our genetic heritage. People whose ancestors belonged to groups who’ve long consumed coconuts may find coconuts more agreeable than people whose fairly recent ancestors lived in parts of the world where coconut trees are nowhere to be found. Coconuts were probably available in some parts of Africa where early humans lived; however, much has obviously happened in the time since Homo sapiens sapiens migrated out of Africa some 50.000-100.000 years ago.
The fatty acid composition of coconuts differs markedly from that of high-fat dairy products and fatty meat products, the two primary sources of saturated fat in the typical western diet. Coconuts are unique in that they are high in lauric acid, a short-chain saturated fatty acid. The effects of this fatty acid on our blood lipid profile and health differ from that of longer-chain saturated fatty acids such as palmitic acid. This helps explain why coconut-consuming traditional people such as the Kitavans are very healthy despite eating a diet that’s fairly high in saturated fat.