1

Polyunsaturated Fat – Omega-3 vs. Omega-6

|

Polyunsaturated Fat

Polyunsaturated Fatty-Acids or PUFAs are the third type of fats the others being saturated and monounsaturated fats. PUFAs are very important fats which are also essential for our health, but we need to deep-dive a bit more and understand how best to incorporate them into our diet for optimal benefits.

This is because in the recent years our diet has changed quite a lot and unfortunately not for the better. This has mostly to do with the rapid increase of the world population and hence the demand for food. The transition from a hunter-gatherer diet to an agriculture based diet means that we rely more and more on grains and also to cheaper sources of food. This has actually been reflected to a huge increase in omega-6 industrial seed oils and at the same time a decrease of omega-3 fats (ALA, EPA, DHA). This balance turns out is one of key elements of health.

 

The basics

There are three type of fat saturated, monounsaturated and polyunsaturated. These words have to do with the chemical structure of the fatty acids.

There is a simple rule to differentiate them.

  • The more saturated the fat is, the harder it will be at colder temperatures. Typical saturated fats are coconut oil and butter
  • Monounsaturated fats solidify somewhat in cold temperatures. Olive oil is high ( around 70%) in monosaturated fat.
  • Highly polyunsaturated fat don’t solidify even they are cold. In this category we find sunflower, canola oil etc.

What is most important though is that stability of those fats under heat. Saturated fats have a higher smoking point and better suited than polyunsaturated  fats which you want to avoid for cooking since they are highly oxidised when heated. We need to make a special notes on vegetables oils since they are very highly processed and should be avoided at all costs.  The structure of PUFAs makes them less stable when exposed to heat. And while a small amount of PUFAs are necessary in our diets, too many of them (especially after they’ve been heated) can cause inflammation and set the stage for developing diseases like cancer.

 

Summary

  • PUFAs are not stable in heat so they should be avoided as cooking oils.

Polyunsaturated fats

Polyunsaturated fats though are essential for health and since the body can’t create them the amount needed we need to get these essential nutrients from food.

Omega-3 fats are a key family of polyunsaturated fats. There are three main omega-3s:

  • Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) come mainly from fish, so they are sometimes called marine omega-3s.
  • Alpha-linolenic acid (ALA), the most common omega-3 fatty acid in most Western diets, is found in vegetable oils and nuts (especially walnuts), flax seeds and flaxseed oil, leafy vegetables, and some animal fat, especially in grass-fed animals. The human body generally uses ALA for energy, and conversion into EPA and DHA is very limited.

Omega-6 fats are also healthy unsaturated fats. Just like omega-3 fats, we need to get omega-6 fats from food in our diet. There are four types of omega-6 fats:

  • LA (Linoleic acid)
  • ARA (Arachidonic Acid)
  • GLA (Gamma linoleic)
  • CLA (Conjugated linoleic acid)

 

A bit of History around the world

Healthy populations, such as in Japan, have a low omega 6:to:3 ratio of around 4:1 or less, which can be achieved on a diet of whole, unprocessed foods. However this ratio has been scewed in the last decades with the increase of demand for faster and cheeper food. This has given raise to processed oil and meat from animals that have been very poorly fed. Currently the ratio is closer to 20:1 for the average person mostly because of eating lower quality foods like fast food, processed packaged meat, grain fed meat and using low quality cooking oils.

Omega-6 fats

Industrial seed oils are not as healthy as they are reported to be. In fact you should avoid them. 

The point of attention here is Linoleic acid (LA), which although is considered essential it should comprise of only 1% of our total diet intake. However currently the average consumption is about 7 to 8 times that amount. 

  • Excess LA blocks the satiety mechanisms of the adipose tissue cells by signalling them to store more fat
  • Excess LA makes the blood more prone to clotting (contributing to heart attacks) and makes blood vessels harder to dilate.
  • LA is pro-inflammatory and cells that contain excess LA can contribute to cellular lever malfunction and resut into cancer. This needs to be counter balanced by decreasing omega-6 and increasing omega-3 which is anti-inflammatory. 
  • LA increases the small-dense oxidized LDL which is found in the plaque that build up in the artery walls.

For this reasons many people, and myself personally, have issues when consuming too many nuts, and they should generally by avoided. It should be also noted that too much Linoleic acid is though to be mess up our satiety signalling and lead to overeating. 

Omega-3 fats

O3 are one of our bodies main anti-inflammatory components and is an essential fatty acid as it reduces inflammation and not only.

They’re key to the structure of every cell wall you have. They’re also an energy source and help keep your heart, lungs, blood vessels, and immune system working the way they should. Two crucial ones — EPA and DHA — are primarily found in certain fish. ALA (alpha-linolenic acid), another omega-3 fatty acid, is found in plant sources such as nuts and seeds.

DHA levels are especially high in retina (eye), brain, and sperm cells. Not only does your body need these fatty acids to function, they also deliver some big health benefits.

Some key notes here

  • ALA independent of the low conversion ratio to EPA/DHA has beneficial effects on blood pressure.
  • Omega-3 is essential in increased amounts (300mg /day) for pregnant women to ensure that the baby gets enough when it is born.
  • It is true that omega-3 fatty acids can increase LDL but unlike omega-6, it tends to increase the benign large particles while reducing the harmful small-dense LDL particles.  
  • Omega-3 increases HDL and reduces triglycerides

Summary

  • Omega-3 as essential fatty acids which are one of the main anti-inflammatory mechanisms in our body.

What to eat and what to avoid

  1. No fast food and deep fried food. The combilation of LA in low quality oils with carbs is leathal as it puts on hold all satiety signals and stores inflammatory compounds in your cells which will cause havoc inside you.
  2. Consume plenty of fatty fish. Choose fresh, wild caught fish, preferably small like sardines.
  3. Reduce consumption of nuts and seeds. Flax seeds and Chia seeds are the only ones with a ratio 03:06 bigger than one. Reduce to walnuts, almonds, etc to a handful in order to keep your O3:06 ratio close to 1:1
  4. Prefer grass-fed beef : Chicken and pork are fine on a weekly basid but grass fed beef has around 2% of LA whereas check and pork more than 10%

Key Takeaways

  • Consume more omega-3 and less omega-6 in your daily life to get into an inti-inflammatory state. Aim for an omega-6/3 ratio of no more than 4:1
  • Increase omega-3 fats to reduce the risk of cardiovascular disease, boosting fat burning and build lean muscle mass. Try this by consume wild-caught fresh seafood, animal products organic, pasture raised and grass-fed.
  • Avoid consumption of industrial seed oils and reduce nuts and seeds

Further Reading