The Four Types Of Fat – Sorting Out the Confusion of Dietary Fats

October 26, 2008

I was going to write a post on dietary fats, because I believe it is crucial to know what is good, what to avoid, etc. Instead of doing a “decent” post on the subject, I asked my friend Scott Kustes of Fitness Spotlight to write an exclusive post for Fitness Black Book.

Scott is the “go to” guy for me when it comes to eating whole foods for maximum health and performance. He is widely respected by the online fitness and nutrition community, because he knows his stuff. He does a great job of taking complex topics and simplifying them a bit.

I highly recommend you go over to Scott’s site and subscribe to his blog: Fitness Spotlight

In fact, you want to read a post that makes you think…then read one of his recent posts: Thoughts On Michael Pollan’s Latest Article “Farmer In Chief”.

pike place market
[Support your local Farmer’s Market. I’m lucky enough to live 5 minutes from the world famous Pike Place Market in Seattle. It started in 1907 and is the longest running farmer’s market in the United States. It feels good to buy from your own community.]

The Four Types Of Fat

Author: Scott Kustes

There are four high-level categories that all fats fall into. You’ve heard of all of these: monounsaturated, polyunsaturated, saturated, and trans fats. There are two configurations for fats, known as cis and trans. Don’t ask me why those names were chosen over “bent” and “straight”…you know how those science types are.

Let’s explore the four types a bit, so we have an understanding of what we’re talking about. Here’s an image of three molecules that I’m going to refer to a couple times, so keep it handy.

Saturated Fat
Saturated huh? Exactly what is it saturated with? Hydrogen. Saturated fats refer to fats in which all carbon atoms are bonded to hydrogen atoms (as opposed to having a double-bond connection to another carbon atom). So looking at the handout (click the link above if you closed that picture that I told you to keep handy…you kids never listen), you can see that the top molecule has no double bonds between carbon atoms and is therefore saturated with hydrogen (i.e., holding as many hydrogen atoms as possible).

Monounsaturated Fat
So then if a saturated fat is holding as many hydrogen atoms as possible, what is a monounsaturated fat? Look at the second molecule in the picture and you’ll see a single double-bond between two carbon atoms. Because these two carbon atoms could each hold one more hydrogen atom if the double-bond were broken, it is unsaturated, and because it is only unsaturated at a single point, it is mono-unsaturated.

Polyunsaturated Fat
I guess you’ve figured out what polyunsaturated means now huh? Poly-, meaning two or more, means that a polyunsaturated fat (the third molecule) has at least two double-bonds between carbon atoms and potentially more. The most commonly known polyunsaturated fats today are the omega-3s and omega-6s. The 3 and 6 refer to a specific location of the first double-bond. I won’t get into because I can sense your eyes glazing already and it’s relatively unimportant.

Trans Fat
Trans fats are the only of the four types of fat that are man-made. Through the process of hydrogenation, hydrogen atoms are added to (typically) polyunsaturated vegetable oils with the help of a nickel catalyst. Contrary to popular belief, high temperature frying and reusing oil does not produce trans fats. These fats can only be produced when nickel is added and hydrogen is forced through an oil at high pressure.

Where Do I Find These Fats?

When talking about fats, it’s important to realize that no fat source is purely saturated or unsaturated. For instance, pork lard is saturated, right? Well, sorta. For illustrative purposes, let’s look at the fatty acids in pork lard: 41% is saturated, 47% is monounsaturated, and 11% is polyunsaturated. Olive oil is 75% mono-, 14% saturated, and 11% poly-. As you can see, these oils aren’t purely one thing or another, but are a mix of various fatty acids.

Moving along, I’m going to paint with a very broad brush here. Foods like nuts and avocados are predominantly monounsaturated fat sources, as are olive and canola oils. Polyunsaturated fats are found in vegetable oils like corn, soy, and sunflower, along with in fish and fish oil. Animal products, including dairy, and the foods made from coconut (coconut cream, coconut milk, coconut oil) or palm oil are the main sources of saturated fat in the diet.

So Which Fats Should I Use?

Easy question, right? Mainly monounsaturated and polyunsaturated fats, keeping saturated fats to less than 10% of total calories, right? Hmm…maybe not. I go the “natural” route when it comes to choosing fats. That automatically knocks trans fats out of the equation. They are man-made unnatural fats and are not good for you in any way, shape, or form.*

What else does my choice of natural fats rule out? Vegetable oils. Okay, so I just lost half of you who have now chalked me up to a quack. To the rest of you, here’s the logic:

  • Vegetable oils come from…vegetables (or grains in the case of corn)
  • Vegetables and grains have very little fat
  • Therefore, it takes HUGE quantities of these foods to make a little bit of oil, quantities far larger than any human could ever eat
  • The extraction methods are suspect and involve such lovely terms as hexane and supercritical carbon dioxide (in comparison, olive oil is extracted by pressing olives)
  • Further processing is necessary to remove impurities and most of the vitamins to enhance shelf-stability
  • Polyunsaturated oils have been shown to suppress the immune system (and are used in organ transplants for this purpose)

Okay, so monounsaturated and saturated fats? Yep! These fats are readily available in nature and are the foods that have been consumed by humans for hundreds of thousands of years. Polyunsaturated vegetable oils are a 20th century creation. There is no evidence supporting the damnation of saturated fats. While polyunsaturated fats are not shelf-stable and need heavy refining, saturated fats are nearly impervious to oxidation and rancidity, owing to their high degree of saturation. They don’t need to be refined and are rich sources of vitamins. It also means these are the proper fats for cooking, as poly- and monounsaturated fats tend to oxidize and spit free radicals throughout your body with application of heat and light.

It’s unlikely anyone will argue with me about monounsaturated fats given their exalted status as a media darling due to the so-called Mediterranean Diet, so I won’t waste your time making you read a treatise on why you should eat them.

To finish this long, winding explanation of the fats I recommend, here’s a list: coconut oil, red palm oil, pork lard (from pastured pigs), real butter (NOT MARGARINE!) and olive oil. I do my cooking in the first four (though don’t use butter much, for no real rhyme or reason) and add the last to vegetables and salads.

One Final Thing

This is just a brush of the surface when it comes to fats. In reality, the three broad categories of natural fats (I’m leaving trans out of the discussion) are just that: categories. All monounsaturated fats aren’t the same, nor are all saturated or polyunsaturated fats the same. As you delve deeper, which we aren’t going to do today, you get into names like palmitic acid, butyric acid, lauric acid, etc.

I say this to point out the underlying reality of fats: it’s far too complex of an area to be condensed to a single talking point of “fat is bad” or “fat is good”.

What are your thoughts on the issue of fat? More is better? Less is better? Any other questions about fat? (I could talk for days.)

* Okay, there are small amounts of naturally-occurring trans fats that appear to have health benefits in a few foods…those aren’t what is measured on the Nutrition Information panel and are inconsequential to our discussion.

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{ 27 comments… read them below or add one }

Methuselah - Pay Now Live Later October 26, 2008 at 2:03 am

Scott, Rusty, nice post and great job on simplifying this topic.

I am currently reading a book that goes into the full detail on fats so I know just how complicated a topic it is. Sounds like you may have plans to cover the separate areas in bite sized chunks in the future, so I am looking forward to that. I am particularly interested in knowing which animal fats I should aim to use. I enjoyed Greg’s post on Modern Forager about the book ‘Fat: An Appreciation of A Misunderstood Ingredient’. So my vote is on the next post covering that!

Yavor October 26, 2008 at 6:49 am

I tend to NOT care about complicated nutritional (or training) facts anymore. I prefer the basics and that is why I like Eat Stop Eat so much – just eat less if you wanna weigh less.

This is why I DO like this article too. Plain and simple.

Eat animal fat, eat olive oil, eat coconut oil, eat red palm oil.

Forget about the other oils that are extracted via advanced 20 century space technology.

Keep it simple and you’ll succeed!

Thanks Scott,


Alex Kay October 26, 2008 at 6:51 am

Interesting, interesting! Fats are the new proteins 🙂 just kidding.

Anyway, I didn’t know about the poly-fats, so I guess I learned something after all today.

Thanks a lot for that, and thanks Rusty for bringing Scott over here!

Take care guys,

DR October 26, 2008 at 1:13 pm

I loved this part of your article:

What else does my choice of natural fats rule out? Vegetable oils. Okay, so I just lost half of you who have now chalked me up to a quack. To the rest of you, here’s the logic:

MSM (Main Stream Medicine in this case) has decided that fat is bad for us and that saturated fat is realllyyyy bad for us.

And they are going to continue to hammer home this idea no matter what the research says.

Personally, I am neither a low-carb, low-fat, Mediterranean or typical Western diet follower.

My job requires me to keep up to date on the latest science.

As such, I am in agreement with what you have written here about fats and human nutrition.

But more than that, I agree with this statement:

I say this to point out the underlying reality of fats: it’s far too complex of an area to be condensed to a single talking point of “fat is bad” or “fat is good”.

Now if only MSM could temporarily suspend it’s hate-on against fats long enough to fund some decent research, we might actually come to the realization that a diet based on empty carbo calories may not be the best choice for our health.

Helder October 26, 2008 at 2:02 pm

Very good information here, a lot of people still think fats are all the same, and that they should all be avoided, but that’s not true, this post clears up all the confusion about it

Andrew R October 26, 2008 at 5:53 pm

Hey Rusty,

What happened to making shorter posts? lol, just kidding. In all seriousness, I really liked the article and I’d love to see more complex issues broken down in this way. It makes it easier for everyone to get a grasp on such issues in a way that doesn’t lose their attention.

Scott: I’ve been a fan of your blog for some time now, thanks for the post!! I really liked the post you just did on red meats and colon cancer by the way.

All the Best,

Andrew R

Son of Grok October 27, 2008 at 10:33 am

Excellent use of your resources Rusty… Scott is always an excellent read. Scott…. excellent read!

Scott Kustes - Modern Forager October 27, 2008 at 12:06 pm

Methuselah, for cooking, I usually use either pastured pork lard or coconut oil. I have rendered beef tallow in the past and used that, but it’s far easier to pay $8 for a tub of lard from a local farmer that lasts for a long time. Some people use goose fat, chicken fat, duck fat, etc. Those all seem fine to me, but for simplicity and storage space, I just have a 4lb tub of pork lard that I keep around.

DR, I think the unfortunate reality is that MSM has to distill things down to just a few words for the lay public. So when the misguided attempt to reduce saturated fat came around, they thought “No one will know what saturated fat is.” So we got “eat less fat”. Now it’s “eat good fats,” which still keeps the idea of “fat is bad” in the public’s mind…if there are “good fats” then there are obviously “bad fats,” right? I suppose it’s part of our soundbite nature where we get most of our news in 30-second bites.

Andrew, I tried to keep it short. It was a lot of work for me! 🙂 Thanks for the kudos.

Thanks for asking me to do this Rusty!


admin October 27, 2008 at 5:19 pm


Thanks for the solid post as well as following up with these guy’s comments.


BurritoKid October 27, 2008 at 10:46 pm


I’ve been thinking about wanting to put on a little bit of muscle. My workouts have always consisted of resistance/cardio together on the same day. My plan is to stop the cardio for maybe a month to try to pack on some strength and muscle. Do you think this is a good idea? Is there a better way to go about building some muscle?

I figure that since we’re moving into the fall/winter months now is the time to do it before cutting down for summer. I weigh around 157 and am 5’9” if that helps.

Yavor October 29, 2008 at 10:31 am


List your working weights and reps on the major lifts:

weighted dips (start without weight if you are too weak)
weighted chins
standing dumbbell shoulder presses
dumbbell alternate curls

Then, make sure to make 1 more rep every workout or every other workout. Do 2 sets of each, 8-12 reps, 3x per week. When you hit 12 reps on your second set, it’s time to raise the weight a bit.

Oh, and get ready to grow!

Muscle growth – simple, but it’s up to you to pay your dues with EFFORT.


David October 29, 2008 at 2:56 pm

Great post.

This may seem like a stupid question but….

I am 6′, 155lbs and I have very low body fat, 5%, and I am lean. But I think when your body fat is too low it is harder to build or sculpt muscle. The way I see it if you have healthy fat or a little extra fat you can sculpt the muscle like wet clay. If you have very little fat it’s like trying to sculpt with dried out clay, so as you tone and tighten a muscle it can cause tears or injuries because of a lack of lubrication.

I started to use extra virgin olive oil last year but had to stop because I found it was actually causing me to burn more fat. Now I eat avocado everyday and a little butter maybe once a week. I also started eating lamb chops twice per week and fillet steak once. I know everybody says red meat is bad but I’m from Ireland and the animals are grass fed. I just find it very difficult to get any results and the lack of fat is leaving my skin and hair really dry and my face looking kinda haggard.

I want to increase my healthy fats without getting flabby. Any advice?

SueT October 30, 2008 at 11:52 am

Just wondering why oil extracted from an olive is better than say, oil extracted from a peanut or a sunflower seed? Must take a lot of those too, no?

Jay October 31, 2008 at 5:25 am


Man, I wish you were my mom/dad/big brother when I was growing up……….

Rendering 10lbs of pork lard this weekend in the garage, as my Duck Fat is getting low. Anyone interested in Duck Fat, check out Hudson Valley at:

Now if I can just save up some bucks for the Foie Gras

Scott Kustes - Modern Forager November 1, 2008 at 5:44 pm

SueT, All three of the foods you mentioned are probably sufficiently oily to make extraction pretty easy. For instance, an olive, you can squeeze the oil out by hand, which is why they can use a press for it. Peanut oil is produced the same way…pressing rather than chemical extraction. Not sure how sunflower oil is produced. The biggest issue with them is that they are very high in polyunsaturated fatty acids, which as I mentioned above are prone to rancidity and oxidation. Further, they are exceptionally high in omega-6 fatty acids, throwing off the omega-3:omega-6 balance more so than most people are already off.

Jay, sounds like you’re more than making up for the animal fats you didn’t eat as a youngster though. =)


Tom Parker - Free Fitness Tips November 2, 2008 at 7:27 am

Hey Scott. Whilst I understand there is no way to fully categorise fats into these four broad categories you have cleared up a lot of the confusion. For example, vegetable oil does sound healthy even though as you say the extraction methods are actually quite questionable.

Justin Case March 9, 2009 at 5:57 pm

Very nice article. I am wondering about the statement of your eating three of the four oils for cooking but not olive oil. If they are of the same class why not use olive oil? I only use olive oil for cooking.

Is coconut oil the only one that does not change structure when heated to a dangerous or unhealthy substance?

I use to use lard, but then I discovered pork has enzymes that will not be destroyed even at temperatures in excess of 2,000 degrees and these enzymes are the cause of trichinosis. Or have I gotten something wrong in the mix?

Very informative post. Thank you.

Jason G April 8, 2009 at 3:27 pm

This article was a great introduction to dietary fats; however I wish this article had a little more info about omega 3’s (more specifically EPA and DHA). There is some evidence(I am not any kind of expert) that show that adding omega 3’s to your diet can help you lose weight by balancing blood sugar and by flushing out bad fats from your body. In regards to David’s comment about adding good fats to your diet my new (after workout) breakfast routine consists of three omega 3 enriched eggs mixed with canned wild salmon and lightly fried red onions-scrambled together. To be fair I am currently on an omega 3 craze but this breakfast routine does include over 50 grams of protein.

C.michael amadi April 21, 2009 at 7:25 pm

thanks for teaching me about coconut oil it was a very interesting about the 3 omega and the 6 omega well thanks for everything

take care,
michael from ny

Brenda May 16, 2009 at 11:28 am

Too many big words!!!! Why can’t we have a dumbed down words that a 5 year old could understand. It’s just too confusing!
You read the definitions and next day you can’t remember which was which. It bugs me so I have no motivation to memorize all these terms.

Just make it easy. Translate into simple terms and use them on food packaging. PLEASE!!!!

A rating system would work….1 to 10. One being safe, 10 being deadly. LOL

Shurron Silva August 19, 2009 at 2:59 am

Wow! Readers do not use coconut oil. It’s extremely high in saturated fat and we all know sat fat is the culprit of heart disease, high cholesterol, and fatty plaque in the arteries. Stay away from Sat fats which mostly come from animal sources and in this case coconut oil. Coconut oil should be mailny used by extremely active people such as Tarzan. People that drive or sit down during the day should not use this type of fat. If you don’t believe me look it up. most of our daily fat intake should come from monounsaturated fats, polyunsat. Fats, and very little if nec. from sat fat. sat fat is the fat that leads to high cholesterol-(body converts it), and cardiovascular disease (fatty plaque) just to name a few. Trans Fat is the gang leader and horrible!!!! Stay away from it, as it provides you with no benefit whatsoever. Unless your Bear Grisley,starving, and need the calories to get up the hill. Trans fat is mainly found in processed oil (MCDonalds), and vegetable shortening products used to make biscuits, pie crusts, do-nots. Its that greasy film on the bottom of those treats that you can feel on the roof of your mouth. i’ve seen it in frozen pizza as well as in wheat tortillas. Good Luck stay healty and stay away from trans fat and limit yourself to sat fat because it can add up to a heart attack-this is why ice cream is bad b/c of the sat fat content. Also the coconut oil is bad for business if you want references I’ll gladly post them.

Sam November 14, 2009 at 7:47 pm

Great Post Shurron!!

vacoder January 30, 2010 at 8:59 pm

I had totally forgotten about this post and your recent post reminded me of the same. Needless to say, excellent post with wealth of information.

Thanks Rusty + Scott

kimone November 13, 2011 at 3:24 pm

i didn’t know much about fat but thanks to you I’ve learn so much thank you.

Cecelia January 22, 2012 at 5:52 pm

What a great & realistic write up! As an CNT (certified nutritional therapist) I am always defending the use of saturated fats. Lucky you to live so close to Pike St.

Karim July 26, 2012 at 7:45 am

CLA, what is that type of fatty acid?

lewisfowler July 29, 2012 at 9:42 pm

From my experience I agree with the monounsaturated or saturated fat suggestion. The polyunsaturated fats are overrated and I believe most damages attributed to them are really caused by refined grains.

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