Is coconut oil healthier? Should you replace your homemade oil with coconut oil?

gossip

As a cooking oil and beauty product, coconut oil has attracted much attention in recent years due to the promotion of some fitness bloggers and celebrities. Coconut oil is advertised as being easy to absorb, not accumulating fat, and helping with weight loss; it contains no cholesterol, increases the body's "good" cholesterol, and is beneficial to cardiovascular health; it is high in vitamin E, moisturizes the skin, and is beautifying. Are these true?

Is coconut oil really worth the hype?

analyze

What is coconut oil? Why is it so hyped?

After we buy coconuts and drink coconut milk, we can see a thick layer of white, chewy coconut meat on the inner wall of the coconut. When we scoop a spoonful into our mouth, it is fragrant and tender. Since the coconut meat has a high fat content, oil can be extracted from it, which is what we call coconut oil.

Coconut oil is popular in the market mainly because it contains medium-chain fatty acids, lauric acid and vitamin E. Beauty and weight loss are the pursuits of most women. If there is a delicious food that can achieve this effect, it will definitely be favored by female friends.

Is coconut oil really healthy?

1. Weight loss theory

The source of this statement is that coconut oil is rich in "medium-chain fatty acids MCT". This type of fatty acid has a relatively short carbon chain (8 to 12 carbons) and is believed to be able to be quickly decomposed and absorbed, so it can quickly provide energy without storing fat. Other commonly used vegetable oils are mainly "long-chain fatty acids" and are prone to fat accumulation.

Why is there such a big difference between "medium-chain fatty acids" and "long-chain fatty acids"?

In principle, the metabolic process of "medium-chain fatty acids" and "long-chain fatty acids" is a bit like two different routes to work. Imagine that "long-chain fatty acids" are regular office workers. After being absorbed by the small intestine, they have to take the lymphatic system bus to reach the subway station where the blood circulates. "Medium-chain fatty acids" are like a cool cyclist who can directly ride a bicycle to the highway where the blood circulates, saving the trouble of waiting for the bus, which is naturally much faster.

Because "medium-chain fatty acids" are fast, they can quickly reach the liver, the "energy factory", and convert into energy to supply our daily needs. In theory, "medium-chain fatty acids" are unlikely to make us fat, and they are more like a diligent energy provider. On the contrary, "long-chain fatty acids", the regular office workers, once consumed too much, can easily "settle down" in our fat tissue, causing us to gain weight unknowingly.

Image source: sciencedirect (translated by the author)

However, the principle is the principle, and the current research results are inconsistent as to whether medium-chain fatty acids can really help lose weight. Although some experiments have found that they can increase satiety and reduce food intake, and some studies have found that medium-chain fatty acids may help reduce waist circumference and weight, other studies have not found obvious weight loss effects. Therefore, although medium-chain fatty acids have good prospects for weight loss, more high-quality research is needed to verify it.

Even if medium-chain fatty acids are proven to be beneficial for weight loss in the future, this does not mean that coconut oil can help you lose weight, because coconut oil is not pure medium-chain fatty acids.

Image source: USDA Food Database (Coconut Oil)

Although coconut oil contains 54% medium-chain fatty acids, the majority of them are lauric acid (C12), which has a longer carbon chain and is metabolized in a similar way to long-chain fatty acids. Currently, research on whether medium-chain fatty acids can help with weight loss is mainly based on C8 and C10. These two fatty acids are truly likely to help with weight loss, but only 12% of them are lauric acid.

In other words, there are very few fatty acids in coconut oil that help with weight loss.

Moreover, coconut oil itself is 99% fat, which is very high in calories. 100g of coconut oil contains 895kcal, which is similar to other vegetable oils. If you use coconut oil to lose weight, you may not lose weight, but gain a lot of fat.

2. Reducing the incidence of cardiovascular disease

There are two main arguments for reducing cardiovascular disease: Coconut oil is rich in medium-chain fatty acids, which can increase the level of "good" cholesterol (high-density lipoprotein cholesterol HDL), which is beneficial to the health of blood lipids. In addition, coconut oil does not contain cholesterol and trans fatty acids, which is good for preventing cardiovascular disease.

Image source: Introduction to a certain brand of coconut oil on an e-commerce platform

But does coconut oil raise "good cholesterol"?

In fact, coconut oil is not only not good for cardiovascular health, but it may increase the risk of heart disease. The saturated fatty acid content in coconut oil exceeds 80%, which is much higher than butter, lard, etc.

Image source: 2015-2020 Dietary Guidelines for Americans (8th Edition)

Let’s take a look at a substantial system review.

A systematic review published in the top cardiovascular journal Circulation in March 2020, by summarizing data from 16 clinical trials, revealed the true impact of coconut oil on health.

(1) Compared with other edible oils, coconut oil significantly increases the levels of "bad cholesterol" LDL and total cholesterol in the blood, and the increase in these two types of cholesterol is closely related to an increased risk of cardiovascular disease.

(2) Coconut oil increases the level of HDL (high-density lipoprotein cholesterol), but high levels of HDL cannot offset the harm of LDL and does not necessarily reduce the risk of cardiovascular disease.

In other words, although it can bring good things, the bad effects it brings are greater.

****In 2017, the American Heart Association (AHA) clearly opposed the consumption of coconut oil in "Dietary Fat and Cardiovascular Disease".

Image source: American Heart Association official website

After reading this, you may not care about what ingredients are advertised or not. After all, the conclusions of experimental research are far more important than publicity.

To help you see the truth, let me tell you two more bugs in the promotion. The promotion mentioned that coconut oil does not contain cholesterol and trans fatty acids. If you know a little about nutrition, this statement will be self-defeating.

Because almost all vegetable oils do not contain cholesterol. Not only coconut oil, but also soybean oil, olive oil, corn oil and other vegetable oils do not contain cholesterol. In addition, if natural vegetable oils are not refined, it is generally difficult to produce trans fatty acids (except hydrogenated or refined vegetable oils).

So it’s a bit unfair to promote in this way.

3. Rich in vitamin E, it can protect skin and beautify

The claim that coconut oil can improve skin and beauty comes from the fact that it contains antioxidant vitamin E. The promotional article for coconut oil describes it this way:

Coconut oil’s antioxidant properties, thanks to its vitamin E content, play a vital role in reducing visible signs of aging. These antioxidants help neutralize harmful free radicals that can cause oxidative stress on the skin, leading to premature aging effects like wrinkles and fine lines.

By fighting these free radicals, coconut oil helps keep your skin healthy, vibrant, and youthful.

But in fact, the vitamin E content in coconut oil is not high.

Judging from the data, coconut oil is inferior to common vegetable oils.

Data from: USDA Food Database

What are the real benefits of coconut oil?

Coconut oil is not completely worthless.

Coconut oil contains a lot of saturated fatty acids. Compared with unsaturated fatty acids, saturated fatty acids have a stable structure and are resistant to high temperatures. So if you want to fry, coconut oil is indeed a good choice.

However, because coconut oil also contains unsaturated fatty acids, it is best to shallow fry it, and repeated frying is not recommended.

in conclusion

Coconut oil is not as magical as the legend says. In summary, there are three points:

1. Although it contains medium-chain fatty acids, only 12% of them may be beneficial for weight loss, so it may not necessarily help with weight loss, but as a fat, eating too much will definitely make you gain weight.

2. It can raise good cholesterol but cannot offset the negative impact of excessive saturated fatty acids on cardiovascular diseases.

3. It contains almost no vitamin E, so don’t expect to use it for antioxidant skin care and beauty.

So, if you want to fry food, coconut oil is a good choice, but don’t have too high expectations if you want to use it to lose weight, beautify your skin, etc.

References:

doi: 10.1161/CIR.0000000000000510. Epub 2017 Jun 15. Erratum in: Circulation. 2017 Sep 5;136(10):e195. PMID: 28620111.

[2]Food Composition Databases Show Foods -- Oil, coconut [Internet]. Food Composition Databases Show Foods. Available from: https://fdc.nal.usda.gov/fdc-app.html#/food-details/330458/nutrients

[3] Yang Yuexin, Ge Keyou. Chinese Nutrition Science Encyclopedia 2nd Edition (Volume 1)[M]. People's Medical Publishing House, 2019

[4]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 Feb;115(2):249-263. doi: 10.1016/j.jand.2014.10.022. PMID: 25636220.

[5]Assunçao, Monica L., et al. "Effects of dietary coconut oil on the biochemical and anthropometric profiles of women presenting abdominal obesity." Lipids 44.7 (2009): 593-601.

[6]Valente, Flávia Xavier, et al. "Effects of coconut oil consumption on energy metabolism, cardiometabolic risk markers, and appetitive responses in women with excess body fat." European Journal of Nutrition 57.4 (2018): 1627-1637.

[7] Hong Kong Department of Health. "Control cholesterol: Eat for a healthy heart" Improvement tips.
https://www.fhs.gov.hk/tc_chi/health_info/woman/30105.html

[8]PG Roopashree, Shilpa S. Shetty, N. Suchetha Kumari, Effect of medium chain fatty acid in human health and disease, Journal of Functional Foods, Volume 87, 2021, 104724, ISSN 1756-4646, https://doi.org/10.1016/j.jff.2021.104724.

This article is a work of Science Popularization China-Starry Sky Project

Produced by: Science Popularization Department of China Association for Science and Technology

Producer｜China Science and Technology Press Co., Ltd., Beijing Zhongke Xinghe Culture Media Co., Ltd.

Planning丨Zhong Yanping

Author: Li Chun, registered nutritionist in China

Review｜Ruan Guangfeng, Deputy Director of Kexin Food and Health Information Exchange Center