Fat. No one really likes that word. But, do we need fat? If so, why do we need fat? And how much do we need? The truth is, fat is a great nutrient. It’s important for our bodies and it tastes great! But just like so many other things in this world, there are healthy options and not so healthy options.
Let’s look at the science behind it (you get to see the nerd in me come out a little here), then we will go more into what types of fat you need and where you can find them.
Why Our Bodies Need Fat
You know those cushy layers under your skin that we are all too often displeased with? Let’s call that fat role #1: energy storage. Our body’s primary way of storing energy for times of famine is through increasing our fat stores. We have a virtually unlimited capacity to store fat. Yay!
As soon as a fat cell gets too full, it divides into 2 fat cells. If you over eat often, you end up with more and more fat cells over time. Once they are created they do not go away. This is part of what makes losing weight and keeping it off so challenging. Each of those cells prefers not to be too empty. I know, it’s not the best thing to celebrate, but if you had to go a few days without food, it will help keep you moving.
Fat also serves as a source of insulation and cushioning. Not just the fat we see, but also the fat we don’t see that cushions our organs, nerves, and body structure.
Fat helps carry around proteins in our blood and deliver them to our tissues. It also is a major part of the walls of each of our cells. In fact, they help keep each cell separate and from oozing into the surrounding fluids. It’s brilliant and awesome how this works!
Fat also helps our bodies absorb certain vitamins, and digest the foods we eat. And muscle-building testosterone? Yup, we need fat for it! Making Vitamin D in the sunshine? Fat is required. How about the estrogen that helps us ladies have babies? You guessed it, we need fat.
What Types of Fat Do We Need to Eat
There are three main types of fats in our bodies: triglycerides (the type in our fat cells), phospholipids (the kind holding our cells together) and sterols (like cholesterol). When eating fats, we are generally referring to triglycerides and that is what is commonly call “fat”. As for the other two, we can make those ourselves (more on that in the section on fats we don’t need).
Generally speaking, when we are looking at what we need to eat, we are talking about triglycerides and the individual fatty acids that make them up… here is a brief rundown on them.
The Fats We Need
Alright my friends, are you ready for a mouthful? They didn’t give the fats names that are at all user friendly, but here we go…
There are two essential polyunsaturated fatty acids: linoleic acid (an omega-6 fatty acid) and alpha-linolenic acid (an omega-3 fatty acid). We need both for overall health.
Linoleic acid is an important part of the structure of our cells. This Omega-6 fatty acid is present in more than adequate amounts in the average diet. Therefore, there are no supply worries. In fact, we tend to get way too much omega-6 in our diet, which is believed to increase inflammation and not be so good for us. Some = good. Tons = eeeehhh. Balance is the key.
Omega-3 fats, on the other hand, get a lot of attention for their health attributes, and since they are not easily found in most of our food items, most of us do not get enough of them. While it is the omega-3 fatty acid deemed “essential”, most of the attention on omega-3s usually goes to EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid), even though they are not technically the essential omega-3s.
Most people have heard of EPA and DHA, less so linolenic acid. Going into all the wonders of omega-3s is an article for another time. For now, know you are far better off with much more omega-3s than most people get. Here is a short version of the benefits for those of you that are not familiar with them.
These three fat beauties help decrease inflammation (and diseases related to it), and improve heart health and vascular health. EPA can be made in small amounts from linolenic acid that we eat (thank you, flaxseed), then from there can be converted (again in smaller amounts) to DHA, in addition to getting both EPA and DHA from our diet.
The piece that most people may not realize is that linolenic acid and EPA+DHA are neither created equal, nor do they provide the same health benefits in spite of them both being omega-3 fats. EPA and DHA are both found in fish oil, so most recommendations regarding fish oil supplements come in the form of EPA+DHA recommendations. EPA+DHA (studied with fish oil supplements) have specifically been evaluated in multiple areas of study for their long term effects on heart health. This has been established in both individual cells and in population based studies looking at areas with high fish consumption rates.
If you are taking fish oil supplements, check the back of the label. Some fish oil supplements have much higher amounts of EPA+DHA than others.
But what about linolenic acid? Is it good for you? Yes, absolutely! Should most people get more of it? Yes, absolutely! Can you just add linolenic acid to your diet, make a bunch of EPA, from there metabolize to DHA, and expect to see the same results as if your were adding EPA+DHA straight from fish consumption. Nope and sorry. This is where your flaxseed fails you.
You read that right. Linolenic acid (flaxseed, chia seeds) and EPA+DHA (fish oil) are not found in the same foods. The improvements seen in heart disease and blood pressure are primarily from EPA+DHA intake, not linolenic acid. That said, you can convert some linolenic acid to EPA then to DHA, but only a small amount (we eat Linolenic acid some -> EPA, and an itty bitty amount of EPA -> DHA). Women are slightly better than men at this (nothing personal, it’s hormone related, after all we do have a lot more fat friendly features). So if you do have heart disease or a family history of it, you need to look at not just putting flax in your oatmeal, but also incorporating fish oils into your eating plan.
So, where does that leave linolenic acid? It’s not useless. Far from it. Especially when you are looking at inflammation and inflammatory diseases. Omega-3s as a whole have shown to beneficially impact inflammation and eye health. Also, though many heart health studies focused directly on DHA+EPA, linolenic acid can still benefit the body as a whole, helping either indirectly or in the long run with heart health. There are also further studies looking into brain health and indirect effects on the nervous system.
In the end, you can spend a lot of time micro-analyzing each (and it is the job of many scientists do do just that!), but the reality is, the omega-3’s are good and you need more of each. They are not the same though, so it is best to focus on getting all of them in your diet. You can, and should, eat fish AND flax. You get the idea.
The Fats We Do Not Need
If you never ate any cholesterol again for the rest of your life, you would be perfectly healthy. Why? Because we make it all by ourselves. Some of us even make excessive amounts, but we all meet the minimum production requirements just fine. We make phospholipids as well, so there is no need to go out of your way to get those either.
We also have no requirement for either saturated fats or trans fats. You could live the rest of your life without either butter or margarine and your body would probably thank you for it. Saturated fats are those that are solid at room temperature, for example beef, chicken, or pork fat. Palm and coconut are the only plant forms of saturated fats. Start checking out food labels; the amount of products using palm oils may surprise you.
Trans fats are found in small amounts in nature but larger amounts in processed foods. When we became health conscious as consumers and started limiting our saturated fat intakes to lower our heart disease risk, the food manufacturers took a bit of a hit. When they tried to produce foods with unsaturated fats, they went bad (rancid) much faster and their shelf life tanked. This was also causing losses on the part of food manufacturers. And no one likes losing money.
So the question became, how do they use healthier fats and have the same shelf life as the unhealthy fats? Enter trans fats. If you just chemically change the structure of the healthy fat so it looks and acts more like the unhealthy fat then — TA DA! — it works!
Unfortunately if it looks like a duck and quacks like a duck… or in this case, if it looks like an unhealthy fat and acts like an unhealthy fat… you guessed it, it’s an unhealthy fat. By making the structural changes, they changed healthy fats into unhealthy ones. It affects your body in different unhealthy ways than saturated fats do, but unhealthy none the less.
Everything considered, neither saturated nor trans fats are good for you. There are people that argue one is worse than the other. While we may be able to prove that in isolated experiments, in the real world you come across both. Butter and margarine, bacon and fried foods. It’s just best to limit them both.
Additional Benefits of Fats
Aside from all the health requirements outlined above, fats play other important roles too. They help you feel fuller not only faster, but they keep you fuller longer. They give meat a juicy, tender, fall off the bone quality. That is why lean cuts of meat are so tough. And it’s why chicken breasts are so much drier than chicken thighs.
And let’s just face it… fat. tastes. great. It’s our biology. We are built to like how it tastes. It contributes to the smell of foods too, which reminds our brain how much we love to eat them.
Fats provide a great texture to foods. They make pastries flaky. Fat-free ice cream will never taste or have the same mouthfeel as full-fat ice cream. Fat-free cheese simply isn’t really cheese (at least not to me, no offense to cheese makers everywhere).
Monounsaturated fats (all you olive oil fans) are also good for you! While they aren’t in the category of “essential for human health”, they are definitely beneficial.
Fat is literally a macro class of its very own.
What Balance Looks Like
So, you’ve made it through the science with me (hopefully I didn’t bore you too much), but what does this all mean? How do you turn this into food and meals?
For starters, you need to have some fat every day. Since fat is the most energy dense nutrient we eat, you do not want to add a ton of it (unless of course you are working on putting weight on, in which case enjoy!).
For starters, you want to limit your intake of saturated and trans fats. These are in animal products, coconut oil, palm oil and processed foods (some are better than others, comparison shopping helps).
Now, add in the healthy fats! First some omega-3’s, the goal is to have some every day. Try to have fatty fish, for example salmon, mackerel, tuna, herring, or sardines, 2-3 times a week (if you are pregnant, or may become pregnant follow those guidelines for fish consumption). If you don’t like fatty fish or simply don’t eat it much, consider (and talk to your doctor about) taking fish oil. Especially if you are at higher risk for heart disease.
Add in other sources of omega-3’s, like flaxseed, walnuts, chia seeds, sunflower seeds, pistachios, and almonds. Try to eat at least one good source of omega-3 fatty acids every day. Along with those omega-3’s you can find other polyunsaturated fats too, including your needed omega-6’s. By having a higher ratio of omega-3’s to omega 6’s you will decrease the overall inflammatory effects of your omega-6 intake.
Next try to have some monounsaturated fats: avocado, nuts, olives, canola oil. Olive oil is among my favorite! Every type of olive oil is not created equal. Some will taste amazing and some are more, well, blah. Cold pressed or first press will taste better. Try different ones — it makes a difference!
Now, if you can take some of your saturated fats and replace them with unsaturated fats, even better! Subbing olive oil for butter, oil based dressing for a cream based dressing, nut butter for butter on toast, salmon instead of steak, you got this!
The Good News
The good news is that no fat is 100% pure. Fats (even lard) are a mixture of saturated, mono and poly unsaturated fats. When we say it is a “saturated fat”, what we are actually saying is that it is “mostly saturated”. The same goes for when we classify something as mono or poly unsaturated too. They are all a mix. So as you work to add in these healthy fats, you will naturally be consuming a healthy balance of fats. So no need to sweat the details.
Now, lets have some lunch! Salmon served with spring mix tossed in olive oil? Yes, please! Plain yogurt with almonds and a drizzle of honey? Awesome! What is your favorite way to serve up a healthy fat?
References and Further Reading
- American Heart Association, Vitamin Supplements: Hype or Help for Healthy Eating
- Academy of Nutrition and Dietetics, What are Omega-3 Fatty Acids
- National Institutes of Health, Omega-3 Fatty Acids