For years, we have been told that eating food containing highly saturated fats will raise the level of cholesterol in your blood, which will then be deposited in your arteries causing cholesterol-laden plaque to develop. This plaque in turn blocks the arteries and leads to your certain demise – usually via a quick heart attack. Such ideas have caused a widespread change in the type of foods we are advised to consume, and natural food sources such as red meat, butter, eggs and palm or coconut based products are wholly discouraged. As a result, for the past 20 years or so, we have seen the emergence of low-fat or zero fat alternative diet trends in the food industry.
Despite the hypothesis and the sheep-like mentality of society to obey and enforce it, one question remains – “How do saturated fats correlate with cholesterol levels when there are differences in their chemical structure?” After all, they are two very different substances and do not link chemically.
A clear look at the molecular structure of saturated fat and cholesterol shows no direct link between the two. This begs the question, how then, are they considered partners in league, causing plaques and blocked arteries?
Before we delve deeper into this discussion, let’s take a stroll back in history to understand how the whole low-fat campaign began in the first place.
In the early 70’s, physiologist Ancel Keys (Ph.D), published a high profile journal about heart disease and the consumption of saturated fat. He chose 7 countries with the highest mortality rate from heart disease and studied their dietary patterns. In the study, he found that where the highest rates of mortality from heart disease were present, there was also a high intake of animal fat, which is rich in saturated fat, leading him to draw the forgone conclusion that there was some level of interrelation between the two.
Presented in this way, it's not difficult to see how saturated fat quickly became known as the culprit causing heart disease, and Keys’ ‘saturated fat vs. heart disease’ study effortlessly became the dominant hypothesis during that era. However, there was an imbalance to be addressed as Keys was able to come out with such a hypothesis only by handpicking countries where heart disease and consumption of saturated fat were high, and leaving out countries with the same kind of diet but where heart disease was relatively low. For instance, he only chose 7 out of 30 countries to support his theory, leaving out the other 23, and when all the other countries were studied, there did not seem to be support for the correlation of saturated fat and heart disease. For example, Americans have higher rates of heart disease in comparison to the French, although the French consume more butter and animal fats than Americans do.
Although the findings from the diets of these other countries contradicted the idea that eating saturated fats cause heart disease, it did not stop the American Heart Association (AHA) from adopting and highly promoting Dr Keys’ hypothesis as educational information to the public during that era. When the media endorsed this, Ancel Keys’s career shot up to another level, and this seemed to attach credibility to his hypothesis, endorsing the belief that saturated fats caused heart disease. Dr Keys however did later conclude that saturated fats from animal, not plant sources, raised cholesterol levels and ultimately lead to heart disease.
WHAT EXACTLY IS SATURATED FAT?
All living organisms contain some form of saturated fat, which is a type of fat with certain chemical properties and is usually solid at room temperature. Most saturated fats come from animal food products, but they are also found in plant oils, such as palm oil and coconut oil. There are a variety of saturated fats, but those found in our food sources are mostly stearic, palmitic and lauric acids. They make up most of the oil components in almost all types of animal meat, and nearly 70% percent of oil in butter and other dairy products.
According to Dr. Haizan of Universiti Putra Malaysia (UPM), a lipid researcher who does extensive studies on palm oil, it is well established that stearic acid has no effect on cholesterol levels. In fact, stearic acid – found in high amounts in plant and animal fat – is converted to a monounsaturated fat called oleic acid in your liver. This is also known as the super heart-friendly fat found in olive oil. So, according to current nutritional science reports, stearic acid is actually beneficial to your heart.
Palmitic and lauric acids, main components of palm and coconut oil, are known to raise total cholesterol. But what has not been reported, according to Dr. Haizan, is that research shows, although both of these saturated fatty acids do increase the bad cholesterol in the body, they raise the level of good cholesterol even higher at the same time. This actually lowers the risk of heart disease. It's commonly believed that bad cholesterol builds plaque on artery walls, and good cholesterol acts as a scavenger to remove it. By increasing the levels of both types of cholesterol, palmitic and lauric acids actually reduce the ratio of bad cholesterol to good cholesterol in your blood. Current research shows that the ratio of good to bad cholesterol is a better predictor of heart disease than the level of total cholesterol alone.
BREAKING INTO THE FORTRESS OF SCIENTIFIC JARGON
Most of the scientific literature on the subject is not readily accessible to the public; and even if one manages to get access to it, one would most likely be put off by the scientific jargon and the hurdle of understanding the bulky subject material. So, we depend very much on the media to provide us with information on health issues. However, the media sometimes gets too many endorsements from the food industry, leading them to feature only stories that favor the industry. This makes the media a not-entirely reliant source of information.
Due to such influences and lack of complete, comprehensive knowledge, it has become a inevitable conclusion that if you wish to prevent heart disease, you should avoid consuming animal fats. While this idea may not be entirely in the wrong, it is misleading in its emphasis. We will attempt now to tell you why this is such.
Here we will discuss three fat/cholesterol issues that we find interests most people.
1. Does saturated fat increase cholesterol levels?
2. How does bad cholesterol or LDL cause heart disease?
3. What are the good types of oil to be consumed?
Firstly, a word on cholesterol. Cholesterol is a steroid that is common in all living things and is mostly found in animal and plant products. Sometimes when people talk about steroids, particularly in the context of athletics, they usually mean anabolic steroids. Anabolic steroids are synthetic hormones modelled on testosterone which causes many harmful side effects if taken excessively and is abused by some athletes to increase their muscle size and strength. However, in this regard, we are more interested in the issue of the steroid called cholesterol and its purported relations with saturated fat.
DOES SATURATED FAT INCREASE CHOLESTEROL LEVELS?
When you consume saturated fats, they are absorbed into the intestinal wall where the saturated fatty acids stick to glycerol molecules to make triglycerides. Then, the triglycerides are rammed together with a transporter known as a chylomicron. These chylomicrons are then circulated via blood throughout the entire body. As they are circulated, the enzymes in the body break down the chylomicrons, bit by bit, and the remnants are then carried to the liver.
In the liver, the remnants are reconstructed into a smaller type of transporter known as a lipoprotein. Lipoproteins are compounds of protein and cholesterol, used to transport chylomicron remnants around the body-as you can see, our bodies go by the maxim of ‘Waste not, want not’. The lipoprotein produced in the liver is known as a Very Low Density Lipoprotein (VLDL). The function of VLDL is to transport lipid to body parts. These VLDLs get circulated in the body and they gradually lose the fat they carry due to enzyme degradation. As they lose fat, they get smaller, transforming from VLDL to Low Density Lipoprotein (LDL), better known as bad cholesterol.
So, does a diet high in saturated fat cause a rise in cholesterol? The answer is yes, as a high amount of saturated fat causes the liver to churn out more VLDLs due to the higher load of triglycerides to deal with, leading to a rise in total cholesterol. But is this as important as the media and food industry would have us believe?
After a meal, the level of LDL is logically expected to rise due to VLDL metabolism. This was the logic employed by most, causing the global tarnishing of the good name of saturated fat. However, now it has been found that even with high levels of saturated fat, LDL levels will always remain constant. Why? Because our metabolic system tightly controls the level of LDL in the blood. It doesn’t matter how many VLDLs are converted to LDLs, the system takes the excess LDLs back into the liver and recycles them into a different form instead of allowing them to roam the arteries.
Instead, research shows that it is the high consumption of carbohydrates or sugar-based products that ups the level of LDLs, especially refined sugars like white pasta, white bread and et cetera. But that’s not all: what’s even more interesting is the discovery that normal LDLs do no harm to your arteries!
So… why exactly are LDLs known as the all important, big bad cholesterol, legendarily feared by all and sundry?
HOW DOES BAD CHOLESTEROL OR LDL CAUSE HEART DISEASE?
What your doctor can tell you at the moment, is that when the level of LDLs in your blood is too high, it will enter the artery walls and form deposits better known as plaque. As the deposits get bigger they restrict blood flow and finally the plaque will cause a total blockage. Think of it as a highway having multiple accidents, and the lousy drivers of the damaged cars pile them up across the road instead of along the road, forming a major roadblock. At the end of the day, no one is going to get anywhere. Similarly, depending on where the blocked artery is, you will have a problem, as arteries are the ‘roads’ in the body with blood acting as ‘cars’ and ‘lorries’, providing oxygen, nutrients and energy and removing waste. For example, if the plaque block is in an artery supplying the brain, you get a stroke. If it is in one of the arteries supplying the heart, a part of your heart stops working-this is commonly referred to as a heart attack.
However, what your doctor does not explain to you is how LDLs get into your arteries. According to Dr. Malcom Kendrix, a doctor and author of many medical books, the cells of the artery walls do not allow LDLs to permeate, due to the difference in concentration of LDL between the outer and inner walls of arteries. In fact 99% of the population have levels of LDL that are too low to be permeable into the arteries.
In one of Kendrix’s essays, he explained that even if the bad cholesterol does leak in when the concentration increases, then it should leak through all artery walls everywhere, and what we should see, therefore, is thickened artery walls full of LDL everywhere. But we do not see that in the arteries of heart attack patients. Instead we see bits of plaque here and there in the artery walls.
So, after years of research, studies and theories we are almost certain that LDL does not cause heart disease. But wait, if LDLs do not cause plaques and thus heart disease, then what does?
New scientific research theorizes that only oxidized LDLs cause heart disease. The oxidized form of LDLs (bad cholesterol) are believed to be easily accepted by the receptors of arteries, allowing them to slip in the walls and form plaques.
But how do LDLs get oxidized?
When LDLs are exposed to oxygen, sunlight or heat, or when you consume too much refined, hydrogenated or rancid oil, it is likely that you will have a high level of oxidized LDLs. That, by the way, are the oils included in all fast foods and instant foods you find in the supermarkets and stores! And they aren’t the only items cooked with refined, hydrogenated and rancid oil!
So now, should the hypothesis collapse into a heap of dust? Well, the ‘fat causing heart disease’ hypothesis serves as great scientific work from former researchers, and just like any other research hypothesis it acts as a precursor to more advanced revolutionary scientific theories, both for and against its argument. Keeping it in mind, we should simply remember the age-old advice: Everything must be in moderation. This includes fat and oils.
Some of the best fats and oils include palm and coconut oil, nuts, avocadoes, and natural oils in animals and freshwater fish. Natural foods provide the healthiest balance of nutrients and oils for our bodies. Avoid refined hydrogenated and rancid oils, examples of which are soy, cottonseed and corn oil. These are hydrogenated oils that increase the amount of oxidized LDLs in your body and lead to dire consequences in the future.
At the end of the day, we find that as human beings who have eaten fats, protein and carbohydrates since we were born, there is nothing inherently wrong in our foods. It is the amount of food which you eat that accounts for your weight gain, loss or maintenance.