2021年5月26日読了時間: 5分

Healthy fats and unhealthy fats

The healthy fats and unhealthy fats

Which types of fats you use play a key role for your health. Since the Macgavan report has published, a lot of people have thought that vegetable oils have been healthy while animal oils have been unhealthy. But the fact is a little more complicated. There are unhealthy vegetable oils and also relatively healthy animal oils. Plus, These days all animal fats are not same because of livestock factories. I will explain that in more details later.

The types of fats

First of all, types of fats are separated into two : saturated fat acid and unsaturated fat acid. The difference between these two fats is that if they are able to connect more hydrogen ion or not. There’s no space to connect with more hydrogen ion in saturated fats, while unsaturated fats still have more space to connect with more hydrogen ion. Hydrogen ion means an electron and getting an electron means oxidative reaction. So usually unsaturated fat is more likely to cause oxidative reaction than saturated fat is.

It sounds difficult to understand which fat is saturated fat and which fats is unsaturated fat. But it’s very easy. You can see it by checking whether it’s liquid or solid at the room temperature. If it’s liquid at the room temperature, it’s unsaturated fat and if it’s solid at the room temperature, it’s saturated fat. So you can see that butter and coconut oil are saturated fats and olive oil, soy oil and corn oil are unsaturated fats.

As I described above, unsaturated fat is easy to get oxidative. That’s why it’s not a good idea to heat these oils. The only exception is olive oil because olive oil contains a lot of vitamins which prevent from oxidative reaction such as B-carotin, vitamin E and vitamin K.

Saturated fat is further separated into two types : short chained tryglycerid and medium chained tryglycerid. The difference between these two types of the fats are the number of carbon which are connected with. Short chained tryglycerid has 6 carbons or less than 6 carbons and medium chained tryglycerid has 7 to 11 carbons. Butter and ghee are classified as short chained tryglycerid and coconut oil and palm oil are classified as medium chained trygrycerid. Unsaturated fat is classified as long chained tryglycerid and these fats have 12 or more than 12 carbons. These fats are vegetable oils and fish oils.

The character of the short chained tryglycerid is to be used as energy quickly. Especially medium chained tryglycerid is to be digested very quickly because the size of molecules is small. It’s digested ten times as fast as long chained trygrycerid. While short chained tryglycerid and medium chained tryglycerid are fit to be heated up, you better not to heat these with higher than 160 degrees centigrade or at least you should not see any smoking. It makes heterocyclic amines’ form and polycyclic aromatic hydrocarbons’ form

which can increase the risk of cancers because they can produce inflammatory properties in our bodies.

Unsaturated fat

Unsaturated fat is further separated into two types : poly unsaturated fat acid and mono unsaturated fat acid. And further poly unsaturated fat acid is classified into two types : omega 3 fat acid and omega 6 fat acid. Omega 3 fat acid has anti-inflammatory effects, while Omega 6 fat acid promotes inflammation in our bodies. Ideally speaking, the rate of taking omega 3 fat acid and omega 6 fat acid should be omega 3 : omega 6 = 1:1 or at least 1:2. But normal people take too much omega 6 fat acid these days. Maybe the rate is omega 3 : omega 6 = 1:20. Omega 6 fat acid is contained in processed foods such as beckons, sausages, ham, etc. and vegetable oils such as corn oil, soy oil, rice oil, safflower oil. And modern people have these foods much more than before.

While omega 3 acid is contained in avocado, nuts, fishes, flax seeds, chia seeds etc. Omega 3 fat acid is separated into 3 types : EPA, DHA and alpha linolenic acid. EPA and DHA are contained in fishes and linolenic acid is contained in avocado, nuts, flax seeds and chia seeds. EPA and DHA have stronger anti-inflammatory effects than alpha linolenic acid. 10 to 15 % of alpha linolenic acid is converted into EPA in our bodies.

Poly unsaturated fat acid is only omega 9 fat acid and it’s almost only olive oil. Not only olive oil is less likely to get oxidative, but also it has anti-inflammatory effect.

Saturated fat acid - short chained tryglycerid

- medium chained tryglycerid

Unsaturated fat acid – poly saturated fat acid – omega 3 fat acid – alpha linolenic acid

- DHA

- EPA

- omega 6 fat acid

- mono saturated fat acid - omega 9 fat acid

Is saturated fat really as bad as it’s said?

It has been said that taking saturated fat has caused myocardial infarction, strokes and arterosclerosis because saturated fat makes blood vessels narrow and clots. It seems to be true that saturated fat makes blood thick. But it can’t explain all. Actually the half number of myocardial infarction clients have normal cholesterol level and two-thirds of myocardial and strokes clients’ vessels are normal or just a little narrower than normal vessels.

The French paradox

While French people, Spanish people and Masai people take a lot of saturated fat, they hardly get myocardial infarction or strokes. It has been called the French paradox.

Also Harvard university has investigated 150,000 sisters who have myocardial infarction. The result was that there was no relation between how much saturated fat they took and myocardial infarction.

Then what’s the real problem?

The real problem is inflammation which is caused by oxidative fat. If oxidative fat exists in the blood vessels, our immune system reacts and sends phagocytic cells to the spot. When these phagocytic cells fight against oxidative fat, they build blood platelets which the shape is arch in the blood vessels. And when these blood platelets are built up, clots are also built up in the blood vessels. During immune cells fight against the inflammation in the blood vessels, further inflammatory properties are sent to the spot. These inflammatory properties rip a film of blood platelets and the blood goes into the inside of blood platelets. The next moment clots are built up and it stops blood flow. And cells or tissues which can not get blood flow any more dye.

So the more oxidative fat you have, the more immune cells react and the more easily inflammatory properties rip a film of blood platelets. In short, low level and chronic inflammation causes cardio vascular health problems.

How to choose saturated fat

While I described that saturated fat is not as bad as it’s said, it’s better to know how to choose animal products because these days, meats and eggs which come from livestock factories contain a lot of omega 6. You may think cows, chickens and pigs are walking around in a stock farm and they eat grass. But it’s not true anymore. In most of cases they are living in a small cage, spend whole their lives there and fed by grains or in the worst case bone powder which is made from dead livestock. They live under strong stresses and are given very unnatural feed. As a result their components change into unhealthy stuff, in other words a lot of omega 6 fat acid. So if you want to buy good animal products, you better to choose grass fed products, although they are a little expensive. Also if you choose natural fishes, you can avoid antibiotics.

The conclusion

You don’t need to avoid animal fats, if the fat is healthy one such as grass fed butter or eggs which come from a vast livestock farm. But my recommendation is to take avocado, flax seeds, chia seeds, small fishes, nuts and use olive oil when you cook something. Also don’t forget to cook it with a low heat!!