The biggest medical hoax of the twentieth century... Is it time to get rid of vegetable oils in cooking?

You must remember one of those margarine ads, the one that puts a smile on the face of the housewife and brings the whole family together at a delicious dining table.

Why not and companies are scrambling to polish off vegetable fats and oils, not only as a healthy and delicious source of fat, but even more beneficial than saturated animal fats derived from dairy products such as beef ghee.

It can be said that advertisements have succeeded for many years, in concert with the recommendations of some scientific institutions, in demonizing saturated animal fats and placing them as a major and sometimes the only culprit in the high rates of obesity, heart disease and diabetes during the twentieth century.

On the other hand, vegetable oils have been at the forefront of the medical scene for more than a century, on the grounds that they raise the proportion of "good cholesterol" in the body, and reduce the proportion of "bad cholesterol", and thus reduce the risk of heart disease and obesity, and thus is a better option than animal fat. .

You may feel relieved to take a bottle of corn oil and put a pot in the pan to cook the eggs, and you may feel comfortable reading the ingredients for the white cheese you just bought that contains "vegetable fat", but you are definitely wrong if you do!

fat family

Fats are an essential nutrient in the human body, as are protein, carbohydrates and vitamins.

Fat acts as an insulator to protect the body from external thermal changes, and it has other purposes, as it is also a rich source of energy, as one gram of them contains twice the calories contained in one gram of carbohydrates, so storing energy in the form of fat provides the body with a rich source of calories in emergency situations. and lack of food, or even fasting (1).

Fats are made of chains called “fatty acids”, and the combination of three of these chains with a short chain of another compound gives us the famous “triglycerides” in medical analyzes.

These fats, in turn, are divided into “saturated” fats, and you find them in the solid state at room temperature, such as butter and animal fat, and “unsaturated” fats, and they are found in a liquid state, ie in the form of oils (2).

Saturated and unsaturated fatty acids (Wikimedia Commons)

Unsaturated fats are divided into "monounsaturated fatty acids", the most famous of which is olive oil, and "polyunsaturated fatty acids", which are found in most vegetable oils used in food that you find in the market.

Unsaturated fats are liquid in their natural state, but they can be converted into a semi-solid by "hydration" to turn into hydrogenated margarine or margarine of a more suitable consistency for use in baked goods and biscuits.

(3)

corn oil birth

It began in 1899, when the first vegetable oil extracted from corn seeds and suitable for human consumption appeared, produced by the American “Hadnat” Mills Company, as a cheap alternative to the expensive and short-lived animal butter, which humans did not know other than that before that date (4).

Corn oil was - and still is - a revolutionary invention that changed the face of the entire world, and changed the way people cook their food since the invention of cooking, and even changed the health guidelines of the most prestigious global medical institutions, and it has been on the throne of healthy fats to this day.

Since 1961, the American Heart Association has recommended limiting your intake of saturated fat to reduce your risk of heart disease (5).

These and similar recommendations came against the background of studies that linked a high percentage of saturated fat in food with a high percentage of low-density lipoprotein (LDL), which in itself is believed to be responsible for the occurrence of atherosclerosis, and at the same time these studies recommended replacing saturated fat in favor of another. Unsaturated as found in vegetable oils.

Studies have not clearly indicated why lipoproteins cause atherosclerosis in the first place, nor what role vegetable fats play in this process, giving a mysterious sinister character to saturated animal fats.

As a result, vegetable oils are in almost everything we eat, from your favorite fries to the diet biscuits you buy at the grocery store.

If you look at the back of a wrapper of chips, crackers, or even chocolate cake, and even some cheese, you'll find one thing everyone has in common is "vegetable oil" and sometimes palm or soybean oil.

And it didn't stop there. By 1911, the American company Procter & Gamble had the opportunity to conquer the market with Crisco ghee, which gives the housewife the advantage of the consistency of ghee and the cheap price of oil.

Made from crystallized or hydrogenated cottonseed oil, this product was the world's first ghee made entirely from vegetable oil (6).

This new product spread like wildfire, and many companies around the world followed the same principle to manufacture vegetable ghee using various types of oils. These hybrid hydrogenated fats invaded all markets, flooding the screens with advertisements and intense propaganda to entice housewives in these products.

The beginning of the danger

But at some point, it turned out that trans fats are worse than everyone expected, as they raise bad cholesterol and triglycerides in the blood, reduce good cholesterol, in addition to raising the risk of breast, colon, obesity, and type 2 diabetes among others. Many other diseases (7).

Despite this, for a very long time, hydrogenated vegetable margarine has dominated grocery shelves, housewives’ cupboards, and restaurant dishes, and its serious risks were only recently noticed, as the US Food and Drug Administration (FDA) issued a decision in 2015 that hydrogenated fats are not safe for human consumption. It must be prevented (8).

The notorious cholesterol has always been associated with red meat, animal fats, and eggs, even though it is also made inside the human body.

The fats we eat with food are dealt with through a group of transporters responsible for delivering triglycerides and cholesterol to and from cells, and these transporters are specifically responsible for the process of atherosclerosis if it does not function optimally.

These carriers are composed of molecules that contain protein and fat together, so they are called lipoproteins, and they have several types, including "high-density lipoprotein" (HDL) and "low-density lipoprotein" (LDL).

These two transporters perform opposite functions. LDL delivers cholesterol to cells, so it is called bad cholesterol, while HDL collects excess cholesterol from cells and delivers it to the liver to be excreted from the body later, called good cholesterol.

For this reason, a high HDL ratio is an indicator of good health, as it prevents the accumulation of fat in the cells of the body far from the liver.

Vegetable fats, especially linoleic acid, lower bad cholesterol, and for a long time this was considered evidence that they were healthier than animal fats, but is this true?

accusation

The incidence of heart disease has increased since the beginning of the twentieth century.

Before the beginning of the twentieth century, heart disease was rare, and ironically the use of animal fats in cooking was also the basis.

But during the next sixty years, that is, after the emergence and spread of vegetable oils, an epidemic occurred, as the death rate from heart diseases caused by atherosclerosis, which feeds the heart, increased (9), in addition to high rates of obesity and type 2 diabetes (10).

It can be attributed to changes in diet or progress in detecting heart attacks before death and then returning them to atherosclerosis, but is it also a coincidence that this rise came in conjunction with the unusual spread of cheap vegetable oils, and their sweeping of markets and homes?

At that point, let's take a closer look at how atherosclerosis occurs, and to do that we have to go back to the proteins responsible for transporting fats within the body.

In their normal state, lipoproteins perform their function of transporting triglycerides and cholesterol between the liver and the cells of the body.

But in the case of ingestion of linoleic fatty acid - the most famous omega-6 polyunsaturated fat found in vegetable oils - lipoproteins become subject to rapid oxidation, which leads to a change in their external shape, making the liver unable to recognize them and remove them from the blood.

When the liver is unable to clean the blood of harmful fatty acids, macrophages intervene to devour these oxidized lipoproteins, and turn into "foam cells" that are deposited in the lining of the arteries and make hardened masses that narrow these arteries from the inside, and consequently, a lack of blood circulation leading to the member in question.

It is worth noting that where there are heart diseases, high levels of oxidized lipoproteins are found.

Not only does linoleic acid cause atherosclerosis, but it reduces the absorption of healthy omega-3 acids found in fish and nuts (11).

(wikimedia)

On the other hand, animal fats lack the presence of linoleic acid, so they do not oxidize quickly when absorbed, but of course they contain more calories than their vegetable counterparts, and raise the level of bad cholesterol in the blood, as we said, but despite that, they do not cause Fat oxidation at the same rate.

the truth

So why do so many studies and research indicate that vegetable oils are healthier than their animal counterparts?

Why do we find that peoples who depend on vegetable oils for their diet, such as the peoples of the Mediterranean and East Asia, have lower rates of heart disease compared to other countries?

(14).

Not only that, a review of several studies on this matter eventually concluded that replacing saturated fats with omega-6 fatty acids led to lower rates of heart disease (15).

Here let's go back to a slightly old study, in one of the largest and most accurate studies ever done in the history of medicine, the results of which were published in 1989, called the Minnesota Coronary Survey.

In the study, researchers compared two groups of patients, one of whom ate food cooked with animal fats, while the other ate food cooked with vegetable oils.

The preliminary results of the study indicated that after a year of adherence to one of the two diets, a decrease in blood cholesterol was observed in the sample that consumed vegetable oils (12).

This result seems intuitive and expected, but several years after the publication of this study, the preliminary data was re-examined, and it was found that people who participated in the experiment over the age of 65 and succeeded in reducing the level of cholesterol in the blood in fact were more likely to die than the other sample.

The ultimate goal of the vegetable oil diet was not to lower cholesterol, or lower rates of heart disease, but it was also supposed to lead to reduced mortality from heart disease, which was not the case in this trial (13).

In the same study, researchers analyzed data from five other similar trials, with more than 10,000 research samples, whose results did not indicate any benefit from a vegetable oil diet in reducing deaths from heart disease.

It is true that vegetable fats reduce bad cholesterol, but accelerate its oxidation, and the researchers predicted that this effect would be dangerous in those over the age of 65, smokers and alcoholics, because their bodies tend to oxidize linoleic acid more than others.

Christopher Ramsden, the lead researcher of the latest study, concluded that the real reason behind the bad reputation that saturated animal fats gained is that the information resulting from the studies has not been published in full, which gives an initial impression that vegetable fats are healthier, without looking at the long-term effect of these fats. And its impact on mortality from heart disease, which is supposed to be the main goal of a vegetable oil diet.

This conflicting information may leave you confused and unable to make the best decision for your health and choose the right source of fat, which is supposed to represent 30% of the source of your daily calories (17).

But science has not reached a satisfactory answer to this question, which is more healthy;

Vegetable or animal oils?

You can always choose moderation in eating all kinds of fats, maintaining a healthy level of daily activity, taking into account your age, current health status, and diseases, and then hopefully we make the right and conscious decision for our health.

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