Coconut oil has been lauded across the internet for it’s health and beauty benefits. But does it stand up under the microscope of peer-reviewed science? Read on to learn the benefits of coconut oil according to science.
- Weight Loss
- Heart health
- Lower blood pressure
- Wound Healing
- Vitamin Absorption
Overwhelmed by all the info? Me too. So I created a quick-reference cheat sheet with all the benefits of coconut oil and all my favorite ways to incorporate it into daily life! Just click the image below to download your cheat sheet.
Basic Facts about Coconut Oil
Coconut oil is a saturated fat, which is a major reason it was viewed as unhealthy for many years. The thing that makes the saturated fat of coconut oil different is thought to be the high abundance of lauric acid (~50%). This fatty acid is a medium-chain triglyceride (MCT) and it is more easily absorbed and metabolised than long-chain triglycerides (LCT). Due to this trait, this fatty acid can be converted directly into energy in the body, similar to a carbohydrate.
Coconut oil can be extracted from coconuts using either dry or wet techniques. In a dry technique, the meat of the coconut is simply dried and then pressed to extract the oil. Wet processing is a little more complicated. In these techniques, processing begins with fresh coconut meat. To extract the oil, one can use centrifuges and pre-treatments including cold, heat, acids, salts, enzymes, electrolysis, shock waves, steam distillation, or some combination. There are also techniques involving hexane, which is a solvent that can increase yield by around 10%.
How Processing Affects Coconut Oil
It is common wisdom that when possible, one should choose oils processed mechanically and without heat (i.e. cold pressed). This is due to a concern that chemical processes leave residues in the final product and that heat damages the nutrients in the oil. Let’s take a look at these concerns.
The biggest concern with chemical processing is the use of hexane. Hexane is a solvent, meaning things dissolve in it. It is used to separate oil from the wet meat of a coconut because it will dissolve the oil, leaving everything else behind. To remove the hexane from the oil, the solution is heated to around 100°C by steam. The vapors carry away the hexane, leaving behind the oil. Although there is much concern that there is a residue left behind, there is no conclusive evidence either way, mostly because not much research has been done. Similarly, there is no conclusion as to how small amounts of hexane in the diet may affect a person’s health. If you can afford it, I would recommend playing it safe and buying oils that have not been processed with hexane. These oils will be marked as ‘unrefined’ or labeled ‘cold/expeller pressed.’
Benefits of Coconut Oil
There is mild evidence that consuming coconut oil can contribute to weight loss. In a 2011 study, twenty overweight or obese people consumed 10 mL of virgin coconut oil 3 times a day for four weeks, while continuing their normal diet and exercise routines. At the end of the study, there was an average weight loss of 0.5lbs, higher in men at 1.2lbs.
While that sounds great, the problem with this study is that there is no control group. With the lack of a control, it cannot be concluded that coconut oil was the cause of the weight loss. In addition, it is well-known that your weight can vary up to 5lbs in a day due to consumption of food and retention/elimination of liquids.
When it comes to claims that coconut oil increases metabolism, thus leading to weight loss, there are several studies that show that coconut oil increases metabolism for short periods of time. In general, these studies compare a diet based on coconut oil to a diet based on animal-derived fats such as better or beef tallow. Across the board, these studies show a metabolic increase in the coconut oil group after one week, but no statistically significant difference after two weeks. (summary of these studies can be found here).
One may suggest that the fat loss is due to an effect on the way the body deposits fat, rather than metabolism. Researchers have explored this idea and have found that while a diet based on coconut oil does reduce the size of fat cells, it does not inhibit their proliferation (increase in number). This same study found no difference in body weight over the duration of the study.
Bottom Line: Coconut oil has no proven effect on weight loss long term, mostly because no long term studies have been done.
Coconut oil has long been lauded as a ‘heart healthy’ oil, reducing the risk of cardiovascular disease by reducing “bad” (LDL) cholesterol.
A quick note to anyone who read the recent review study published in the summer of 2016 claiming that LDL cholesterol isn’t actually linked to heart disease, see the commonsense review of it here. TLDR: it’s probably biased and fails to present enough evidence to discredit the link.
Working under the previously established link between LDL cholesterol and a higher risk of heart disease, we can evaluate studies that measure cholesterol levels for diets based on different fat sources.
One of the most recent studies on this topic, published in 2003, tests 3 different diets in women:
- High fat, coconut oil based (38.4% of calories from fat)
- Low fat, coconut oil based (19.7% of calories from fat)
- High fat, polyunsaturated fat based (38.2% of calories from fat)
This research group found that women in both of the coconut oil based groups had the same levels of LDL cholesterol and total cholesterol. In contrast, the third diet showed lower levels of LDL and total cholesterol than the coconut oil diets. HDL “good” cholesterol was higher in the high fat coconut oil diet than the low fat coconut oil diet. Additionally, the ratio of bad/good cholesterol was higher in the low fat coconut oil diet than the high fat coconut oil diet. From this, and a few other details I won’t go into here, the researchers concluded that the amount of fat in the diet was more of a factor in cholesterol levels than the type of fat (assuming that both types of fat are high in lauric acid).
The bottom line here seems to point to two things: 1) Good fats (coconut oil being one) have the power to lower bad cholesterol and thus the risk of heart disease and 2) depriving yourself of a healthy amount of fat, even if the little fat you consume is healthy, will raise your risk of heart disease.
Lowers Blood Pressure
As you might have guessed, exercise can be a great way to deal with hypertension, or high blood pressure. However, according to a Feb 2015 study, you can do even better by including coconut oil along with your exercise. Well… at least it works in rats.
In this study, rats who exercised and were supplemented with coconut oil (2 mL per day) showed lower mean arterial pressure and a higher baroreflex, both signs that their blood pressure was going down.
And it seems coconut oil is effective even without exercise. In a 2013 study, also on rats, researchers found that coconut oil lowered the blood pressure of rats even when they were simultaneously consuming 5 times heated palm oil (a control oil pretty much guaranteed to raise blood pressure).
Bottom line: Coconut oil is effective at reducing blood pressure, especially when combined with exercise and in the absence of “bad” fats.
Researchers from Thailand found in 2010 that coconut oil displayed anti-inflammatory properties. Inflammation was induced in rats in a variety of ways, and in each instance, coconut oil rats showed lower inflammation than untreated rats. However, the positive control rats who received anti-inflammatory drugs (acetaminophen, ibuprofen) showed significantly lower inflammation than all doses of coconut oil tested.
A similar study the next year, 2011, had similar results, but noted that coconut oil seems to be more effective on acute (short term) inflammation than chronic (long term) inflammation.
Interestingly, an older study from 1994 found that cod liver oil reduced inflammation in rats better than both coconut oil and groundnut oil.
Bottom line: Coconut oil does have anti-inflammatory properties, but it’s not the most effective choice to combat inflammation. Perhaps as a carrier oil with another anti-inflammatory oil it could work synergistically.
An intriguing study out of India showed in 2010 that virgin coconut oil helps heal excision wounds in rats. Specifically, the coconut oil helped wounds heal faster than if they had been left alone, and the oil was not compared to any other wound-healing products.
This seems to be the only study of it’s kind, but it presents an interesting possibility. Combined with lavender oil, which also has wound healing properties, this could make a wonderful wound treatment.
Lauric acid, a major component of coconut oil, has been lauded as an antiviral and antibacterial agent. Specifically, it has been found to be effective against:
- Vesicular stomatitis virus (Ref)
- Gram positive bacteria (Ref)
- Listeria monocytogenes (common food-borne pathogen) (Ref)
- Heliobacter pylori (colonizes the stomach and causes gastritis, dyspepsia, stomach and duodenal ulcers, and gastric cancer) (Ref)
- Enveloped viruses, meaning viruses with a lipid membrane (specifically visna virus, polio virus type I) (Ref)
The role of fats in vitamin absorption has been widely studied, particularly because 4 essential vitamins are fat-soluble (A, D, E, and K). However, it seems that the type of fat can have an effect on the absorption of these vitamins into your tissues.
As early as 1961, researchers found that coconut oil increased absorption of vitamin A in tissues when compared to groundnut oil, sesame oil, and safflower oil. This could be due to the lauric acid content of coconut oil, because other oils tested are primarily oleic or linoelic acid-based.
More recently, researchers from the University of Illinois published results showing coconut oil increased cartenoid absorption when compared to safflower oil. Cartenoids, such as beta carotene, cannot be synthesized by animals and must be consumed through the diet.
Bottom line: Coconut oil aids in vitamin absorption; this property can be exploited by choosing coconut oil for stir frying your veggies or adding coconut oil to your fruit and veggie smoothies.
In addition to the wide variety of health benefits, coconut oil is also a useful addition to a natural beauty routine. While you can find hundreds of uses for it with a quick google search, I’m only going to cover two major uses: skin moisturizer and hair conditioner.
Coconut oil has a long history of use as a skin moisturizer in tropical cultures. While few scientific studies have been done on coconut oil as a moisturizer, there is one notable study that makes a scientific case for it.
In this study, coconut oil was studied as a moisturizer for people with xerosis (medical term for abnormally dry skin). After two weeks of twice-daily application of oil, patients reported increased skin hydration, and researchers measured a statistically significant increase in skin surface lipid levels.
If you’re looking to replace your current moisturizer with coconut oil, I have a few tips for you from personal experience:
- Never use coconut oil on your face; it is comodegenic and will clog your pores
- Use coconut oil sparingly, as it is easy to over-apply and end up with extra oil that your skin can’t absorb
- If your budget can take it, I would recommend argan oil over coconut oil as a moisturizer: it absorbs into your skin faster and can be applied to your face as well.
Coconut oil’s moisturizing properties make it a good candidate for a carrier oil to use with essential oils. By adding a few drops of essential oil to your coconut oil moisturizer, you can take a simple moisturizer and turn it into a powerful therapeutic rub. My favorite use of this combination is a few drops of stress away (Young Living blend) in my coconut oil to rub on my legs and feet before bed to de-stress and wind down for the night.
Coconut oil’s other most commonly recommended use is as a hair conditioner. Most beauty experts will suggest that you apply coconut oil liberally to your hair, let sit for at least 30min, then shampoo out.
The reason this is such a common beauty practice is illuminated in this study from 2002, which shows that coconut oil reduces protein loss in hair. The researchers propose that this is due to the molecular structure of coconut oil, which allow it to penetrate into the hair shaft.
That’s a lot of uses for coconut oil. If you now feel overwhelmed, I feel ya. That’s why I made this handy pdf you can download with a list of the benefits of coconut oil and a few of my favorite ways to incorporate it into my daily life.