Note: The content of this article is based off off a speech titled "The Oiling of America" that can be viewed here I've also read an essay of the same name available here. If you wish to learn more about the arguments that I am about to put forth I advise you look to these sources as that I will really only be echoing arguments from there. They have more credibility that I do.
So when I was in the Philippines it was quite common for me to talk to people that were convinced that eating meat was unhealthy this claim from many people there was not religiously motivated like a lot of things are but many Filipinos genuinely believe that consuming meat leads to heart problems. Whenever I heard this my American mind always voiced the words, "I like steak," and I'd be a bit puzzled since the meat to rice consumption ratio of Americans was nearly equal to a Filipino's rice to meat consumption ratio. If these Filipinos were right then we'd be seeing a lot more Americans dieing from eating meat.
Of course this war on meat consumption is not exclusive to the Philippines, and according to many "professionals" there is good reason for it. Contrary to what the media might tell you the leading cause of death in America is not some crazy virus, nor is it crazy white people. The leading cause of death in America, and much of the rest of the world, is heart disease followed by cancer. According to "professionals" heat disease is caused by having high cholesterol due to eating too much animal fats mostly coming from red meats, cream and butter, things that Americans love to eat.
Now I do agree that our diet probably has a lot to do with our risk for developing heart disease, a healthy diet should be our best weapon against any disease. But of course the question remains, what exactly is a healthy diet? Vegetarianism and veganism have steadily been on the rise as propaganda for these diets has been increasing, but of course very few people are actually willing to give up meat these diets are of course problematic since there are a lot of nutrients that we need that are hard to find outside of meat. Another diet that was being pushed in recent memory was the paleolithic diet. The philosophy behind the paleolithic diet does have some validity since it blames a lot of the health problems we are facing today on the overabundance of processed foods in our modern diet. Pushers of the paleolithic diet propose that we eat like our paleolithic ancestors did since back in their day nobody was dieing from heart disease, cancer, or diabetes. Of course the problem with this is who today actually knows what cavemen were eating? According to these people our paleolithic ancestors were quite politically correct and mostly ate fruits, vegetables, nuts, according to them they did eat meat but only sparingly and only the lean cuts of meat, many "paleolithic recipes" also call for the use of things like canola oil. Now, I don't know what history books these people are reading but I'm pretty sure that cavemen didn't know how to make canola oil and you'd honestly have to be a fool to believe that cavemen (or about anyone alive before the industrial revolution) would not try to take advantage of the whole animal when they killed one. The paleolithic diet, much like most other diet fads, is a joke.
But the general idea behind the paleolithic diet is good, heart disease, cancer and diabetes really haven't been a huge problem for all that long, but we don't have to go back to caveman days to see how people were living before those problems came about, we don't have to go much farther back than 100 years or so. So what were Americans eating back in the late 1800s? This question we can accurately answer because we still have cookbooks that were published in that time period. So what was in these cookbooks? Lots of fatty red meat, lots of butter, lots of cream (made from unpasteurized milk), everything was cooked with animal fat or butter rather than oil, vegetables were almost never served raw, lettuce was nearly nonexistent and salads really just seemed like an excuse to eat cream or butter based sauces, oysters and other mercury laden seafoods were common, the only oil that was really ever used was olive oil and that was quite rare, foods were fried in tallow or lard and people would eat organ meat so that they could take advantage of the entire animal when they killed one and have enough meat to be able to eat meat with every meal. So really our ancestors were eating all of the things that modern dietitians are telling us not to eat and yet they were free from heart disease, cancer and diabetes. If that kind of diet worked back then there is no reason that it shouldn't work now, this is the type of diet we should be striving for.
The 1920s saw the emergence of corn oil on the market. Corn oil was of course a cheap alternative to animal based fats that had traditionally been used in cooking. As time progressed many other vegetable based oils came to the market as well as other oil based products, margarine to replace butter and oil based shortening to replace tallow and lard. These products were marketed as a healthy alternative to animal based fats and they began to be adopted by the public. This marketing was based on something which came to be known by some as the lipid hypothesis. The lipid hypothesis states, "that saturated fat and cholesterol from animal sources raise cholesterol levels in the blood, leading to deposition of cholesterol and fatty material as pathogenic plaques in the arteries."  This hypothesis should sound familiar to many, in 1956 the American Heart Association had a television conference air on all three networks in which they taught this hypothesis as fact and encouraged Americans to stop eating animal fats and transition to vegetable and corn oil based alternatives. The problem the lipid hypothesis was that despite the marketing it has been proven false. High Cholesterol has not been proven to be a definite cause of heart disease or heart attacks. 
There are two main types of fat found in foods today saturated fats, unsaturated fats. The molecules that make up saturated fats are mostly straight so they are packed together easily and typically solid at room temperature and easier for our bodies to work with, examples of these are animal fats such as butter, lard and tallow, they are also found in things like milk cheese and cream. Unsaturated fats however have a more curly molecular structure so they are naturally liquid at room temperature (but solid when refrigerated) since they don't pack together as easily, cooking oils are all examples of unsaturated fats. The curly nature of these molecules also makes them harder for your body to utilize much of it goes to waste. Of the cooking oils olive oil is the best for your body so if you need to use cooking oil you should go for olive oil whenever possible. Generally speaking saturated fats are better for you than unsaturated fats.
This actually does a lot to explain why many of my Filipino friends thought that meat was so bad for you. If you were to cook chicken adobo and refrigerate it you'd find that your chicken would all be buried in solidified unsaturated fat. Contrast this with a common Filipino vegetable dish, like this one for squash where oil is only used when needed to keep stuff from sticking to the pan and you can see a huge difference between a typical meat dish and a typical vegetable dish in the Philippines. Almost all meat in the Philippines is cooked with excessive amounts of oil while vegetable dishes typically contain almost no oil. The squash dish isn't healthier because it is vegan, it is healthier because it is not served swimming in oil. Meat is not killing Filipinos, oil is.
But what about vegetable oil based margarines and shortenings, they are made of unsaturated fats but they are solid at room temperature how does that work? Margarine and shortening are made possible by a chemical process known as hydrogenation. During hydrogenation the hydrogen molecules in the unsaturated fat compounds are rearranged so that the overall shape of the molecule straightens out and resembles the shape of an unsaturated fat molecule. This process of rearranging atoms produces a lot of free radicals, or atoms with unpaired electrons, within the fat molecules. The presence of these free radicals makes it very easy for the margarine or shortening to spoil, free radicals are also harmful to the body since they could easily bond to a plethora of things within your body which could cause damage to cells, accelerate aging, or cause disease. We should not be putting these substances into our body.
Trans fat is another incredibly dangerous form of fat which was commonly found in margarines, shortenings and other products when these things first came about. Luckily doctors did find and publicise the danger of trans fats in the 80s and today they have been almost entirely eliminated from store shelves so we usually shouldn't have to worry about those anymore.
We can see that there are obvious risks involved with eating the unsaturated and hydrogenated fats which dietitians are pushing on us. They are not as healthy and harmless as advertised.
In the 1960s a study was conducted following two large groups of American men, one group ate a traditional animal fat and meat laden diet while the other ate the American Heart Association recommended diet which emphasized vegetable oil based fats and limited red meat and cholesterol consumption. By reading the abstract (which is all most doctors do) of the paper which reported on the results of this study you'd be lead to believe that the AHA's recommended diet was a great success because those participants had much lower cholesterol on average, but only if you read the fine print of this study would you find that eight of the participants on the AHA recommended diet died of heart disease during the course of the study while none of the participants on traditional diets had any heart disease related problems.  The goal of this study shifted from finding a way to prevent heart disease, America's top killer, to trying to lower cholesterol, something both the food and medical industries could capitalize on.
In 1984 the Cholesterol Consensus Conference was held. In this conference it was determined that adults with cholesterol levels above 200 mg/dL were "at risk"* despite the fact that the studies which these doctors were citing showed 240 as the better risk point. By saying that adults with cholesterol above 200 mg/dL were at risk the doctors had classified the majority of Americans as patients in need of cholesterol lowering drugs, and further study, these doctors were more loyal to the drug companies than they were to the world's population. Since then doctors and drug companies have been successful in lowering the average cholesterol of Americans, but the number of deaths from heart disease and heart disease related illnesses has not decreased. Lowering cholesterol has not saved lives.
I guess that with all this talk of lowering cholesterol we should probably look at what cholesterol actually does and whether or not we should be lowering it. Cholesterol as you have likely guessed is a chemical compound commonly found in animal fats, our bodies also naturally produce cholesterol since acts as an antioxidant. As an antioxidant cholesterol is an important tool for our body to naturally be fight off heart disease and cancer. Cholesterol is also required for the function of our brain's serotonin receptors. Serotonin (like dopamine) is one of our body's "feel good" chemicals, it is one of the reasons that we are able to feel happy. Many people who feel violent, depressed, or suicidal often have low cholesterol and likely feel the way that they do because their lack of cholesterol has hindered their ability to take advantage of serotonin. Mother's milk is also something that is rich with cholesterol, it is believed by many that cholesterol is necessary for the proper growth and development of babies and small children. Cholesterol is also something that our bodies use for repair, scar tissue is filled with a lot of cholesterol. It has been said that, "Blaming heart disease on high serum cholesterol levels is like blaming firemen who have come to put out a fire for starting the blaze." 
Low cholesterol will also inhibit our body's ability to produce important stress relief hormones along with sex hormones like testosterone and estrogen. Our ability to produce Vitamin D, an important vitamin which helps our immune system fight off viruses, helps our bones grow strong, our pancreas produce insulin, and many other things, will also be hindered. If our ancestors survived for so many generations free of ailments such a heart disease, cancer, and diabetes on an animal fat based diet then it makes absolutely no sense for us to abandon such a diet.
We need to always be wary of what we are putting into our bodies. A few months ago I was out fishing with my grandpa, his body is breaking down and he struggles to walk on boat ramps and docks. At the end of that trip once we had the boat back on the trailer and everyone was back in the truck he said something along the lines of:
Getting old is no fun, you don't want to get old but the alternative to that is dying and you don't want to do that either, so you need to live your life in such a way that getting old won't be so bad.
One of the ways that we ensure that getting old won't be too bad is by maintaining a healthy diet. I'm not saying that we can't treat ourselves every once in a while, but I do believe that we should stay away from things such as unsaturated fats, processed foods, and foods with an excessive amount of sugar. Traditional diets kept humans healthy for hundreds of years, these are the diets that we should be trying to replicate. Don't go on some fad diet of questionable quality, don't immediately start eating whatever the "latest breakthrough" in dietary science is, stick to tradition, make it taste good of course, but stick to eating the foods that have been proven to keep us free from disease.
At some point in the 20th century the concept of relative risk came about so that the actual risk of something could be easily obfuscated and exaggerated. For example a drug advertisement may say, "Users of drug A are five times less likely to suffer from condition X than people who do not use drug A." This uses relative risk as a metric and hides the actual risk from us, it may very well be the case that the actual risk of the average person suffering from condition X is 0.00005% and the user of drug A has a 0.00001% chance of getting it, if this is the case then drug A is probably not worth your time and money. Always be wary of the words risk, chance and likely in this context, these words are probably being used to hide something.
 S. Fallon and M. G. Enig, “The Oiling of America,” The Weston A. Price Foundation, 29-Mar-2006. [Online].
Available: https://www.westonaprice.org/oiling-of-america-in-new-york/. [Accessed: 18-Jan-2021].
 G Cristakis, “Effect of the Anti-Coronary Club Program on Coronary Heart Disease Risk-Factor Status,” JAMA, Nov 7, 1966, 198:(6):129-35