Most people have heard a lot of different opinions about eating fats. Are all fats OK to eat or should one or two types be off limits? Should you eat polyunsaturated fats or monounsaturated fat? There must be few people who don’t know that trans fat isn’t good for your health but what about saturated fat, good or bad?
Fat is a nutrient and your body requires fat for energy, to help you to absorb vitamins and for your brain. However, the evidence is clear, you should avoid trans fats as if they were radioactive.
We’re here to look at some real science and see what it says about the consumption of saturated fat and the impact, if any, that it can have on our health.
There are three main types of fat:
- Saturated fat – from vegetables and animal products
- Unsaturated fat – polyunsaturated and monounsaturated
- Trans fats
The evidence is clear that trans fats are bad news for your health, and equally clear that unsaturated fats are good for your health.
Unfortunately the picture is less well-known or understood when it comes to saturated fats.
The war on saturated fats is a long and dodgy one.
One disease more than any other has been blamed on eating saturated fats: Cardiovascular and heart disease.
Heart disease, which is one of the conditions linked to saturated fats in nearly every ones mind, wasn’t really a big deal for us until about one hundred years ago, when the rates of this skyrocketed.
Scientists looked for a reason that heart disease was becoming so common, and finally it was decided that the cause could be laid firmly at the feet of saturated fats.
But why was this explanation so readily accepted? Even just a quick look at a few of the assumptions this opinion made should be enough to see that it really doesn’t make a lot of sense.
For a start, we humans have been wolfing down saturated fats in meat for thousands of years, with no big effect on our hearts at all.
Then suddenly, one hundred years ago, the same fat that we’d been eating since the beginning of time stopped being a great food, and started to ruin our health? Yeah, sure..
So whose idea was it that heart disease could be blamed on saturated fat consumption?
It seems like one man, namely Ancel Keys, pointed the accusatory finger at fat way back in 1955 at the World Health Organization. He studied groups of people with high rates of heart disease and found they ate a lot of saturated fat.
Keys delivered his study known as the lipid hypothesis. In a nut shell this stated that fat raised cholesterol and cholesterol caused heart disease.
Yep, just one man’s words, and later his now famous Seven Countries Study.
He first blamed fats, then specifically saturated fats. He later (1958) began his study known as the Seven Countries Study that proved, he claimed, that in those countries where people ate higher levels of saturated fats, their rates of cardiovascular disease were also high.
What was less well-known is that the populations in the countries in his study also had a very high consumption of refined carbohydrates and sugar. This wasn’t seen as an issue at the time, and remained largely unknown for many years.
Keys had decided the main bad boy was saturated fat, and the American Heart Association (AHA) saw no reason to not believe him.
The AHA didn’t look too hard at the evidence before they started lecturing people about the need to reduce saturated fats or pay the price with their heart and/or obesity.
So successful was the bad press about saturated fats that most people dropped it from their diet, almost never questioning the original study.
People – and especially food manufactures – sought to replace all those tasty saturated fats with man made alternatives such as margarine and vegetable oils, which are often hydrogenated and studies have shown they can increase the risk of heart disease.
Trans fats were suddenly the “healthy” option.
The rates of cardiovascular and heart disease climbed to new and shocking levels.
Even once other scientists did take a closer look at the work of Keys, and spotted some glaring errors, nothing changed mainstream opinion.
Many scientists pointed out that keys study was seriously flawed, but no one was listening. The view of saturated fats as the enemy had filtered through into “common knowledge”.
Most people simply accepted it as fact, an obvious truth that needed no further examination. This “fact” continues to inform much of the public policy to this day.
Even as other previously rare diseases such as diabetes and obesity became common place at the same time as the advice was given to avoid saturated fats, virtually no one was asking the one most important question:
If we stop eating saturated fats, what are we replacing them with?
Why did saturated fats remain the enemy for so long?
One of the reasons for this is that although the truth had been outed, it was a complicated truth, revolving as it did around the complex issues of different sorts of cholesterol, and what cholesterol can and can’t do within our bodies.
Saturated fats raise the levels of a type of cholesterol that you don’t want, LDL, sometimes referred to as bad cholesterol, but at the same time it raises the HDL or good type of cholesterol.
It turns out that it’s the ratio of LDH cholesterol to total cholesterol which is a predictor of heart disease, not the LDH cholesterol levels alone.
To complicate matters even further these two types of cholesterol come in differing sup types too, but suffice to say here that because saturated fats both raise bad cholesterol, and raise good cholesterol ( remember it’s all about the ratio) there is no scientific basis for blaming heart disease on saturated fat.
Other research demonstrated that when people with high LDL (bad) cholesterol stop eating saturated fats, they lower one kind of LDL (the large particles type A), but not the small, type B LDL which are caused by a diet high in carbohydrates, and associated with heart disease.
A UCLA study (2009) showed that three quarters of hospital patients admitted with myocardial infarction did not have a high total cholesterol.
So by concentrating on levels of total cholesterol was a mistake. It’s just not that simple, and by doing this the rates of heart disease have gone up, not down.
So who is the real bad boy ?
It turns out there are two main bad boys: High levels of carbohydrates, especially sugars and trans fats.
This is so well-known now that not too much needs to be said about how bad trans fats are for your health. Just to recap, here are a few of the unpleasant things that trans fats can do to your body:
- Increase levels of harmful cholesterol, at the same time lower levels of good cholesterol.
- Increase levels of heart disease
- Harm insulin function
- Increase inflammation
100 years ago, sugar was a very small part of our diet, and heart disease was a very rare thing.
Even when it first became more widely available in the 1600s it was expensive, and only the rich could afford some of it. However, things slowly changed and consumption over the next few hundred years looked like this:
- 1700 – 1.81kg/3lb 16 oz per year
- 1800 – 10.2kg/22lb 8oz per year
- 1900 – 40.8kg/90lb per year
- 2009 – 50% of Americans were now eating a staggering 81.6kg/179lb per year*
*Data provided by Dr Mercola.
Sugar in its many forms, glucose, sucrose and fructose are now in just about every processed food you can buy. Only naturally occurring fructose such as that found in fruit is OK to eat, but in moderation.
Some fruit ( but not fruit juice) has plenty of health benefits, but fructose by the shed load is very bad news for your body and your metabolism.
Too much sugar in any form can cause:
- Addictive behavior as it increases dopamine in the brain.
- Plays havoc with blood/glucose levels.
- Contributes to increased risks of heart disease, diabetes, certain cancers and obesity.
- Causes tooth decay.
So are saturated fats good or bad?
We need to be clear about saturated fats; your body needs them.
Saturated fats make up almost 50% of your cell membranes and the vast majority of fat in your brain cells is saturated. Your lungs rely on a layer of saturated fat to keep flexible and strong.
Also, if you were to completely deprive your body of saturated fat, it has the ability to make its own out of carbohydrates, up to 10g per day (1) if you’re on a very low fat diet.
A 2010 study in the American Journal of Clinical Nutrition concluded that there was not enough evidence to support the idea that saturated fat increases the risk of heart disease and by substituting it with carbohydrates, the rates of heart disease increase.
Saturated fats contain different types of fatty acids including stearic acid, palmitic acid, and lauric acid.
Stearic acid is found in animal fats. Research shows that stearic acid does not increase the rate of heart disease. Suggesting it’s either neutral or good for you. Stearic acid is broken down into a monounsaturated fat, oleic acid. The same type of fat that is a major component of super healthy olive oil.
Even some plant based sources contain very healthy forms of saturated fats such as Lauric acid.
Coconut contains high levels of saturated fats. However, this high saturated fat food actually contains about 50% of it’s saturated fatty acids in the form of Lauric acid, a medium-chain triglyceride (MCT) aka C12.
C12 may be a saturated fat, but it’s a hero and is used for its antibacterial, antimicrobial and antiviral properties. It’s great for maintaining a healthy level of gut bacteria too.
Lauric acid does increase HDL cholesterol, but there’s no need to worry. When your level of HDL cholesterol is high in comparison with your total cholesterol this study has shown that it is associated with a reduced risk of heart disease.
Other great fatty acids found in saturated fats include capric acid and caprylic acid. These MCT oils have many health benefits, you can read more about them here MCT oil for keto.
The biggest source of saturated fats are animal products. Meats such as beef contain more saturated fats than chicken. This type of fat can also be found in nuts and in some plants such as coconut, coconut oil and palm oil.
Saturated fat is also found in cheese, butter, milk, cream and butter.
These are good sources of saturated fat and come with a healthy dose of protein and minerals.
There are also bad sources of saturated fat, in goods such as pizza and baked goods. These types of foods come with a very unhealthy load of sugar and trans fats.
As long as you are choosing healthy saturated fat containing food which is nutritionally dense, this fat should have a place in your diet.
When you consider that there is much evidence now of people staying on the high fat keto diet for many years, then it would seem that saturated fats are not the enemy at all.
There is much evidence now of these people having very healthy levels of cholesterol despite enjoying higher than normal levels of fats in their diet.
It would seem that the greatest problem for heath is not saturated fats alone, but the tendency to eat them together with unhealthy sugars and/or trans fats as is often the case in ready-made or processed foods.
As long as you are choosy about where you get your saturated fats from, there are many good reasons to make sure you include them in your diet.
Great choices include:
- Grass fed meat, especially beef and lamb.
- Chicken with skin.
- Full fat dairy products such as cream, cheese and yogurt.
- Free range eggs
So, saturated fats should play a part in a healthy diet as long as they are obtained from whole foods, such as dairy or meat.
They also play their part in helping your body to absorb all the nutrients (vitamins and minerals) that you need, can help you to feel full after a meal and are necessary for many vital processes and structures within your body.