Monounsaturated Fat: Is It So “Good” After All?

Monounsaturated fats are regarded by most as ‘good fats’ and ‘heart-healthy’. 

Meanwhile, saturated fats are demonised and labelled as ‘bad fats’ that should be avoided. 

Over the last century, our energy intake from fat has increased by around 700 calories per day, coinciding almost perfectly with our ever-growing obesity rates. 

While many point to the monounsaturated fats like olive oil as the magical ingredient in the Mediterranean diet, most of the extra energy we’ve consumed comes from palm, soybean, and sunflower oils, which are also primarily monounsaturated fats. 

Maybe it’s time to stop and consider if we might be getting too much of a ‘good thing’.

In this article, we’ll look beyond the simplistic ‘good’ vs ‘bad’ labels to understand the relationship between monounsaturated fat, polyunsaturated fat, saturated fat, and other critical factors like satiety and nutrient density

This article will give you a better understanding of how much of each fat you should consume to achieve your goals.

How Has Our Monounsaturated Consumption Changed Over the Years? 

The chart below shows the change in calories from varying types of fat over the past century.  Also plotted are the US obesity rates, which have tracked eerily close to the extra calories from monounsaturated and polyunsaturated fats.  

Since 1910, we have added a whopping 700 calories per person per day to our plates!  Most of this extra energy from fat comes from monounsaturated and polyunsaturated fats.  In contrast, saturated fat has increased by about 100 calories per person.   

The following chart shows how the percentage of our total energy from polyunsaturated and monounsaturated fats has steadily risen, while saturated fat rose until the 1960s and then fell. 

Early last century, saturated fat was the dominant type of fat.  But after research in the 1950s linked saturated fats to heart disease and the 1960s Green Revolution industrialised our food production, monounsaturated and polyunsaturated fats took the lead. 

What Are Monounsaturated Fats? 

Monounsaturated fat and polyunsaturated fat are both classed as unsaturated fats.  Monounsaturated oils are typically liquid at room temperature but solidify when chilled.  In contrast, saturated fats are known for being solid at room temperature.

From a chemical standpoint, monounsaturated fats are fat molecules with one (mono) unsaturated carbon bond, which forms a double bond.

Saturated fats contain only saturated carbons or single-bonded carbon molecules, and polyunsaturated include multiple double bonds. 

Why Are Monounsaturated Fats Often Considered Good Fats?  

Since the 1930s, scientists have suspected dietary fat and cholesterol could cause atherosclerosis, heart disease, and stroke.  Sclerotic plaques form blood clots and narrow arteries (atherosclerosis), contributing to heart disease.  These plaques consist of oxidised cholesterol.

Because saturated fat is solid at room temperature, it was thought that dietary saturated fat and cholesterol from animal-based foods were directly correlated to oxidised blood cholesterol and the hardening of arteries. 

However, recent research has proven this to be an inaccurate oversimplification.  The relationship between dietary cholesterol and blood cholesterol seems to be a bit more complex.

First and foremost, you have bigger problems to contend with if your arteries are at room temperature; you’re already dead! 

But aside from this, cholesterol is an essential molecule necessary for human life.  We need cholesterol to build human tissues and synthesise cell membranes, bile acids, and hormones. 

Whether you’re consuming dietary cholesterol or not, your body makes around 85–90% of the cholesterol it needs.  The rest tends to be absorbed from your food through the intestines.

Oxidative stress has been shown to impair cholesterol metabolism, and new research has also linked it to gut imbalances, poor methylation (which is a result of nutrient deficiency), and environmental toxins, in part from the food we eat.  

Instead of simplistically blaming cholesterol, we might see more success if we begin to question why so much extra cholesterol is floating around the bloodstream. 

Interestingly, while saturated fat is officially still considered ‘bad’, dietary cholesterol was removed as a nutrient of concern in the 2015 Dietary Guidelines after its ‘link’ to heart disease was dismissed. 

Interestingly, our satiety analysis shows that cholesterol and omega-3 fatty acids are the two fats we appear to crave more of, as indicated by the fact that we consume fewer calories when we consume more of these fats per calorie. 

Like saturated fat, cholesterol has decreased in our food system as our food production has become more industrialised.   

For more detail, see Cholesterol: When to Worry and What to Do About It.  

Which Foods Are High in Monounsaturated Fat? 

The tables below list the proportion of energy and relative nutrient density (ND) scores from monounsaturated, saturated, and polyunsaturated fats for a range of popular foods.

The key thing to note here is that most whole foods contain a mixture of mono, poly, and saturated fats.  Also, as we will see later, foods with a higher % of energy from fat tend to have a lower nutrient density.

Although low-fat and plant-based proponents tend to advocate for monounsaturated fat, while low-carb and animal-based diet fans usually support saturated fat, the reality is that all food contains a blend of all three in variable amounts.   

Fats

FoodMono (%)Saturated (%)Poly (%)ND Score
olive oil74%14%11%3%
avocado oil72%12%14%0%
almond butter48%6%20%32%
lard45%39%11%1%
beef tallow42%50%4%2%
cashews40%13%13%32%
peanut butter36%12%22%19%
fish oil29%20%40%0%
butter25%57%4%5%
cream cheese23%52%4%17%
mayonnaise22%15%59%6%

Plants 

FoodMono (%)Saturated (%)Poly (%)ND Score
avocado55%12%10%31%
pecans53%8%28%20%
almond flour50%6%19%33%
almonds49%6%19%34%
peanuts39%13%23%34%
pistachio nuts37%9%23%34%
Brazil nuts33%22%33%30%
sesame seeds29%11%34%40%
hummus25%6%11%35%
flaxseeds13%6%48%39%
walnuts12%8%65%24%
natto10%7%26%58%

Animal

FoodMono (%)Saturated (%)Poly (%)ND Score
bacon38%29%14%23%
pepperoni37%32%8%31%
liverwurst37%29%7%46%
salami37%27%7%22%
Braunschweiger35%26%9%49%
liver pâté35%27%9%41%
egg yolk33%27%12%49%
headcheese32%20%7%21%
duck eggs32%18%6%63%
ground beef31%27%2%41%
whole egg23%20%12%65%
ground chicken23%14%9%60%
Gruyere cheese22%41%4%46%
ham shank22%16%7%64%
roast beef22%19%2%59%
Brie cheese22%47%2%44%
ground turkey21%16%16%59%
Edam cheese20%44%2%47%
blue cheese20%48%2%45%
Greek yogurt20%22%4%24%
provolone cheese19%44%2%46%
Swiss cheese18%42%3%46%
corned beef16%15%2%51%
Parmesan cheese15%33%3%44%
chicken hearts14%16%16%65%
pork ribs14%12%5%62%
ground pork (lean)11%9%4%63%

Seafood

FoodMono (%)Saturated (%)Poly (%)ND Score
herring21%12%12%66%
trout20%7%9%63%
anchovy16%9%11%74%
caviar/roe16%14%25%68%
salmon11%6%8%66%

Nutrient Density vs Monounsaturated Fat 

Offering some insight into the nutrient density component, the chart below shows the relationship between nutrient density and monounsaturated fat.  Here, we see that foods with more monounsaturated fat tend to contain fewer essential micronutrients per calorie. 

To dig into this a little more, the micronutrient fingerprint chart below shows that foods with the most monounsaturated fat are low in most vitamins and minerals.  We see that foods high in monounsaturated fat tend to be particularly low in vitamins C, K1, A, folate (B9), niacin (B3), thiamine (B1), magnesium, and potassium.

Aside from vitamin E, refined vegetable oils like rapeseed, sunflower, and canola, commonly added as ingredients to processed foods, contain negligible amounts of vitamins, minerals, and amino acids

Even the form of vitamin E that is abundant in these oils usually isn’t optimal for the body! 

Is Monounsaturated Fat Better or Worse than Other Types of Fat? 

The following chart shows the relationship between nutrient density, total fat, and each fat fraction.  The vertical axis represents the % of fat from each type of fat.  Overall, we see that polyunsaturated, monounsaturated and saturated fats have a similar relationship with nutrient density.  That is, a higher percentage of energy from fat, regardless of the source, aligns with a lower nutrient density

If you were to look at a snippet from Cronometer of a fat source — let’s say, olive oil — you would see there was little in the way of micronutrients like vitamins, minerals, and amino acids.  

How Much Monounsaturated Fat Aligns with Weight Loss? 

Next, we come to the topic you’re probably most interested in – satiety

In other words,

  • how do different fats influence the quantity of the foods you eat, and
  • does one fat help you lose more weight than another?   

Unfortunately, the short answer is no. 

There is no magical fat that you can eat more of to lose weight. 

Keep reading to learn more! 

Monounsaturated Fat vs Calorie Intake

The chart below shows the relationship between monounsaturated fat and calorie intake from our Optimiser data analysis.  Once we consume more than 10% of our total calories from monounsaturated fat, our overall calorie intake increases significantly. 

Saturated Fat vs Calorie Intake

The following chart shows the relationship between calorie intake and saturated fat.  While more saturated fat aligns with a higher calorie intake, we see a peak relationship between satiety and saturated fat.  Once we consume more than 30% of our calories from saturated fat, we begin eating a little less

It’s not exactly clear why this occurs, but it may be because whole foods with a significant amount of saturated fat, such as cheese and meat, also contain protein.  We know from our satiety analysis that protein is the most critical nutrient for feeling full.

Another factor that may be at play is that saturated fat results in the onset of insulin resistance more quickly than unsaturated fat.  While this would typically be considered unfavourable for saturated fat, it’s helpful to remember that insulin resistance occurs when we exceed our Personal Fat Threshold.

When your fat cells are relatively empty, your appetite increases, and you will be motivated to seek more food.  However, once you approach your Personal Fat Threshold and become insulin resistant, your appetite will settle because you can’t store more energy as efficiently. 

To put it more simply, you become insulin resistant more quickly from overconsuming foods that are high in saturated fat.  Hence, satiety kicks in at a lower body fat level.  Meanwhile, unsaturated fats will keep you eating and gaining much more weight before you finally develop type 2 diabetes

This does not necessarily mean saturated fat is better; it’s just something to be aware of. 

Consuming more energy than you use—from any source! —will result in weight gain.   You don’t want to overdo your fat intake to the point that you drive yourself to become diabetic, but saturated fat might slow you down before you become morbidly obese.

Polyunsaturated Fat vs Calorie Intake

Finally, as shown in the chart below, we also tend to eat more energy when our diet contains more polyunsaturated fat. 

Comparison

When we look at the satiety response to all three types of fat together, we see a similar response. 

From this analysis, it’s hard to conclude whether one fat is better than another.  However, we see a clearer signal when we look at all fats taken together. 

Reducing fat from 80 to 40% of calories aligns with a 28% reduction in energy intake!  Although fat is an excellent slow-burning energy source that often comes packaged with protein, it is the most energy-dense macronutrient.  Thus, it is the easiest to ‘leverage’ or increase or reduce to alter your overall energy intake to align with your goals. 

What Is the Minimum Amount of Monounsaturated Fat? 

To help you understand the possible range for each fat, the table below shows:

  • The % intake of each type of fat in the US diet in 1910 vs 2010, and
  • The 15th, median, and 85th percentile intakes from our Optimiser data. 
1910201015thMedian85th
Polyunsaturated3.4%9.9%3.4%6.3%10.4%
Monounsaturated11.9%17.3%8.8%15.7%24.0%
Saturated13.2%13.3%8.7%16.5%26.1%
Total Fat30.9%41.9%35.3%45.8%61.7%

This data is also plotted in the chart below.  Note that the US population’s polyunsaturated fat intake has nearly tripled over the past century.  Monounsaturated fat has increased by 50% over the past century.  Meanwhile, our health has deteriorated, and obesity has climbed on. 

The table below is not intended to be used as a hard-and-fast rule or even a guideline; we just wanted to include it to show some of the ranges our data analysis suggested.  All values are in per cent of total calories.

  • If your goal is to maximise nutrient density and satiety, your intake of each fat should be closer to the lower end of the range. 
  • But if you are lean, active, or on a lower-carb diet, you might increase your intake towards the upper end of this range. 
LowerUpper
Polyunsaturated3.5%10%
Monounsaturated10%25%
Saturated9%25%
Total Fat30%60%

How Do I Find the Right Fat Intake for Me? 

Instead of demonising or prioritising fat, you may have more success finding the amount of dietary fat for you if fat itself isn’t your focus.  To find the right amount of fat for you, you can follow these simple steps:

  1. Ensure you’re getting adequate protein,
  2. Dial in your carbohydrate intake to ensure that your blood sugar levels are healthy and do not rise by more than 30 mg/dL (1.6 mmol/L) after meals, and finally
  3. Add energy from fat to support your activity or reduce your dietary fat if your goal is body fat loss. 

Rather than micro-managing saturated vs mono vs poly fats, set the nutrient density of your diet as your highest priority.  Once you focus on what matters, the right fat ratios will fall into place. 

We always see diet quality suffer if you demonise ‘bad’ components in food and non-sensical results.  A recent example of this can be found in our article Is Tufts University Food Compass Nutrient Profiling System ‘Broken’?

But if you’re getting plenty of nutrients from whole foods, you won’t need to micromanage ‘good’ vs ‘bad’ fats.  Instead, everything will fall into place without getting too much or not enough of anything you do or don’t require. 

Which Fats Should You Avoid? 

Since you’ve made it this far, you see that you probably don’t need to be afraid of any one fat, so long as it comes from whole foods that contain enough other essential nutrients.   

While we like to romanticise the ‘heart-healthy’ Mediterranean Diet, the reality is we’re not all getting an extra 700 calories per day from eating too many avocados or walnuts or adding too much avocado oil or olive oil to our salads!  Right?    

In truth, the massive increase in our fat intake has come predominantly from industrial seed oils such as palm, soybean, sunflower, and rapeseed are super cheap, high-profit-margin ingredients that manufacturers love adding to processed foods.   The following chart shows that our intake of these oils has increased by more than 800% over the past half-century!  

It’s a convenient ‘coincidence’ that the US Department of Agriculture’s Dietary Guidelines gives them a ‘heart-healthy’ blessing while demonising saturated fats.

What Foods Should You Avoid?

Very few people are overdoing these refined oils by themselves.  How often do you get the urge to dump soybean oil on your salad?  

While these unsaturated oils alone aren’t so appetising, they become a real problem when combined with refined flour and sugar in ultra-processed foods. 

The ingredients list for the Oreo cookie shown below is a prime example.  Palm or canola oil is the primary ingredient after flour and sugar!   

The following Cronometer screenshot shows the macro profile of 2000 calories of Oreo cookies.  We see they contain a blend of carbs and fat with minimal protein —the recipe for hyper-palatable junk food.   

Now, look at the micronutrient profile for 2000 calories of Oreo cookies, which shows how terrible their nutrient density is.  Most of the nutrients they contain are from fortification!

While this might be disgusting and frightening to see, the problem is that Oreo cookies are not unique.  This formula of industrial seed oils + sugar + flour + flavourings +colours + synthetic fortified vitamins is the signature of most packaged foods in the centre aisles of our supermarkets and fast-food stores. 

The Bottom Line

If you value your health, worry less about which types of fats you are getting in your meat and nuts. 

Instead, avoid processed foods that contain substantial amounts of industrial seed oils as ingredients, and do it like your life depends on it. 

You won’t need to be concerned about ‘good fat’ vs ‘bad fat’ if you rely primarily on nutrient density to determine whether a food is ideal for you. 

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