Cholesterol and Saturated Fat Myth: Bad Cholesterol May Not Be So Bad (2023)
For decades, low-density lipoprotein (LDL) cholesterol was one of the most critical indicators that doctors measured for heart disease. Now, doctors and researchers are challenging whether LDL cholesterol, also known as “bad cholesterol,” is really as bad as we once feared. Research shows that measuring LDL cholesterol doesn’t always effectively assess a person’s cardiovascular risk and that other tests may be more useful.
Low-Density Lipoproteins Versus LDL Cholesterol
Many people with normal LDL cholesterol levels may experience heart attacks, cardiovascular research scientist James DiNicholantonio told The Epoch Times via email.
The number of LDL particles, rather than LDL cholesterol, may be a more relevant risk factor.
Studies have shown that LDL cholesterol levels predict higher cardiovascular risk 40 percent of the time, while apolipoprotein B (apoB) concentration, the summation of all LDL particles and their precursors, is associated with elevated risk 70 percent of the time.
Other studies comparing LDL cholesterol levels against cholesterol levels in LDL and its precursors, apoB number, and LDL particle number, also found that the latter two tend to be stronger predictors of risk, while LDL cholesterol is the weakest.
So what’s the difference between LDL particles and LDL cholesterol?
An LDL particle is a type of lipoprotein made by the liver. Its primary function is to deliver triglycerides from the liver to other cells in the body. Transporting cholesterol is more akin to an LDL’s side hustle. The cholesterol that an LDL transports is called LDL cholesterol.
High-density lipoprotein (HDL) and LDL cholesterols contain the same cholesterol; their carriers are what differ. LDL cholesterol can also leak into blood vessels, causing atherosclerosis, thereby earning its “bad” reputation.
On the other hand, HDL particles can venture into atherosclerotic plaques to absorb the cholesterol trapped inside, preventing further plaque formation and helping to prevent heart disease. Hence, HDL cholesterol is considered “good.”
Therefore, nutritionist Jonny Bowden says labeling HDL and LDL cholesterols as good and bad cholesterol is wrong. Mr. Bowden and cardiologist Dr. Stephen Sinatra wrote the bestselling book “The Great Cholesterol Myth.”
Mr. Bowden said measuring LDL particles is like knowing the number of cars traveling on the road. We know that more cars means more congestion and traffic accidents. But LDL cholesterol doesn’t always indicate this.
LDL cholesterol is like the car passengers, not the cars themselves. Many passengers might indicate that traffic is highly congested. However, traffic could still be congested even if passenger numbers are low or average.
“My LDL [cholesterol] was like 100, maybe 110 mg/dL; very, very close to ideal,” Mr. Bowden said. “Then I got the particle tests, and they showed an entirely different picture.”
The test showed that he carried many small, dense LDL particles in his blood and was at high risk for cardiovascular events.
2 Types of LDL, 1 Is More Harmful
There are two types of LDL particles: large and buoyant, and small and dense.
The small and dense LDLs are much more atherogenic (contributive to atherosclerosis), whereas the large, buoyant LDLs are less so. These two types of LDLs can be measured through advanced lipid testing.
About 80 percent of total LDL cholesterol level comprises the more harmless large, buoyant LDLs, with atherogenic small, dense LDL making up the rest.
Interestingly, fats increase large, buoyant LDLs and decrease small, dense LDLs, whereas refined carbohydrates increase small, dense LDLs. Professor Erik Froyen from California State Polytechnic University, who has a doctorate in nutritional biology and whose research investigates mechanisms by which fatty acids impact cancer and cardiovascular disease risk factors, has also demonstrated this in his work.
Some research suggests that intake of refined carbohydrates is more relevant than saturated fat in causing coronary heart disease.
Mr. Bowden compares large, buoyant LDLs with large volleyballs that float along in the water, moving with the tide, while small, dense LDLs are like small golf balls that get stuck between rocks, where they start oxidizing and accumulating to form atherosclerotic plaques.
Individuals with more large, buoyant LDLs are said to exhibit a pattern A type of cholesterol profile, and these people are at low risk of atherosclerosis.
On the other hand, those with more small, dense LDLs exhibit a pattern B cholesterol profile and are at risk of atherosclerosis. Their markers for metabolic disease risks may also be elevated.
Small, dense LDLs carry less cholesterol than large, buoyant LDLs, so a person can have a normal LDL cholesterol level but a pattern B cholesterol profile.
Lipidologist professor Carol Kirkpatrick from Idaho State University, however, highlighted that for most people, overall LDL particle number is more relevant than LDL size.
“What we know now is that, yes, [small dense LDLs] may be important, but it really ends up being a red flag for people who have metabolic dysfunction,” she told The Epoch Times.
Ms. Kirkpatrick is also a registered dietitian nutritionist and the director of the Idaho State University Wellness Center.
Some studies have found that large LDLs have a neutral effect on atherosclerosis, though other scientists disagree.
“We know that statins, for instance, lower cardiovascular risk, and statins preferentially reduce larger LDL particles,” said professor Kevin Maki of Indiana University, whose interest is in preventing and managing cardiometabolic disease.
However, the statin and LDL link has also been challenged.
“It’s really unclear if the benefit of statins is because it lowers LDL,” cardiologist Dr. Robert Dubroff told The Epoch Times.
“There are other drugs that can lower LDL, and many of them have been tested in well-conducted randomized trials and shown no benefit.”
Dr. Dubroff indicated that there are interventions that lower cardiovascular risk without lowering LDL.
Coronary Heart Disease: A Multifactorial Disease
Cardiovascular disease can be caused by various factors unrelated to LDL particles and LDL cholesterol.
Age is the most significant risk factor for cardiovascular disease, Mr. Maki said. The same is the case for one’s blood vessels and the blood vessels’ inner linings as he or she ages. Damage to the lining can result in inflammation, which raises LDL particle levels and may precipitate atherosclerosis.
Inflammation is also recognized as a risk factor, encouraging plaque formation and elevating LDLs in the bloodstream.
Insulin resistance is also increasingly recognized as a major contributor. It strongly correlates with Type 2 diabetes, which doubles the risk of death from heart disease or stroke.
Professor Benjamin Bikman from Brigham Young University told The Epoch Times that he sees two sides to insulin resistance: hyperinsulinemia, meaning high blood insulin, and actual insulin resistance, where the body no longer sufficiently responds to insulin.
Hyperinsulinemia encourages the formation of small, dense LDLs rather than large, buoyant ones. Insulin also increases blood pressure and encourages endothelial growth inside blood vessels, both related to atherosclerosis.
Dr. Dubroff said a patient who suffered multiple cardiovascular events was transferred to him a few years ago. The patient underwent coronary artery bypass three times and had been treated aggressively with statin medications, but his cardiovascular events continued.
Dr. Dubroff noticed that his patient’s blood sugar was borderline prediabetic and that he was overweight and had high blood triglycerides and low HDL. However, none of these risk factors were addressed by previous doctors.
He told his patient that the correct way forward was to improve his diet, lose weight, and exercise more.
Dr. Dubroff followed this patient for an additional 10 years.
“He never had any additional problems, even though his cholesterol level did not change,” Dr. Dubroff said.
Regarding tracing the source of one’s heart disease, Mr. Maki said: “I would say it’s not this or that, it’s this and that. LDL cholesterol is a factor; particle concentration is a factor; insulin resistance is a factor.”
Addressing all risk factors instead of one will enable us to be the “most successful at reducing cardiovascular risks,” he said.
Better or Add-Value Tests
The advanced lipid test can better identify high-risk people with normal LDL cholesterol profiles. The test usually looks at LDL particle numbers or apoB numbers, which provide the total number of a person’s non-HDL lipoprotein particles.
Non-HDL particles include VLDL, IDL, and LDL particles. VLDL and IDL are precursors to LDL particles, so a high non-HDL particle number suggests high LDL particles.
However, advanced lipid testing usually isn’t covered by insurance. Therefore, health professionals sometimes offer alternative markers for examination.
Mr. Maki said that if he could only pick one thing to examine, he would choose non-HDL cholesterol, colloquially known as the “poor man’s apoB.”
This test is covered by insurance and looks at all the cholesterol carried in the non-HDL lipoproteins. While it provides a weaker predictive value than apoB, it can give a general indication of whether more particles are traveling in the bloodstream.
Mr. Bowden and Mr. Bikan suggested the triglyceride-to-HDL ratio to calculate insulin resistance.
When a person’s insulin levels are high, it encourages the destruction of HDL particles while encouraging blood triglyceride production. This leads to more LDL particles, especially small, dense, atherogenic LDL particles in the blood.
Markers for inflammation may also be suggestive of atherosclerosis. Inflammation can cause C-reactive protein (CRP) levels to become elevated. CRP can enter blood vessels and create an atherogenic environment.
The Saturated Fats Good for High-Heat Cooking
For half a century, health agencies and experts have recommended vegetable oils over saturated fats for cooking. They have told the public that vegetable oils are cardioprotective. However, research suggests these oils may not be as innocuous as they seem.
While saturated fat has historically faced criticism due to its association with blood cholesterol levels and coronary heart disease, emerging studies have provided a more nuanced understanding of this topic, including this fat’s potential advantages in high-temperature cooking.
Compared to polyunsaturated fats, saturated fats exhibit greater stability when exposed to heat and oxygen. However, the type of saturated fat and its smoke point still determine how they should be used appropriately.
The following is a list of vegetable and animal oils known for their significant saturated fat content.
Coconut Oil
Coconut oil, obtained from the fruit of the coconut, is composed of around 90 percent saturated fat. However, coconut oil is generally considered less stable for cooking despite its high saturated fat content.
This is because most coconut oils are short- to medium-chain fatty acids, less stable than longer-chain saturated fatty acids (pdf). As a result, unrefined coconut oil tends to have a lower smoke point of around 350 F or 177 C.
Refined coconut oil has undergone industrial processing, resulting in a higher smoke point of about 400 to 450 F, making it more suitable for high-heat cooking. However, the refining process removes the unique flavor, aroma, vitamins, and antioxidants.
Coconut oil can be used for low-heat cooking, such as sautéing and frying. It’s also preferable for baking.
Almost half of the fat content in coconut oil is comprised of lauric acid, a type of saturated fat known for its antimicrobial properties.
Palm Oil
Palm oil, derived from the fruit of palm trees, is a vegetable cooking oil known for its stability. Approximately 50 percent of palm oil is saturated fat, with an additional 40 percent being monounsaturated fat.
Virgin or unrefined palm oil has a smoke point of 455 F and derives its deep red or orange color and carrot-like flavor from palm fruit’s abundant beta-carotene content. On the other hand, refined palm oil is tasteless and appears white. Palm oil’s smooth, buttery texture makes it a popular choice for baking, and it serves as a rich source of tocotrienols, the most potent form of vitamin E.
Palm oil, the most widely used vegetable oil, is commonly used as a low-cost fat in processed foods, which tarnishes its reputation.
Palm kernel oil, extracted from the seeds rather than the fruit’s flesh, is also used to prolong the shelf life of processed food. With approximately 80 percent saturated fat content, palm kernel oil is more stable for commercial cooking and frying. However, palm oil contains more antioxidants than palm kernel oil.
The direct health implications of high saturated fat content in palm oils remain a subject of ongoing debate. Some studies suggest that consuming palm oil may also have cardioprotective effects.
“The healthiness or otherwise of a processed food is usually determined by the degree of processing it has undergone, as well as the addition of other ingredients such as preservatives, flavors sugar, salt, fats … and not simply the addition of palm and palm kernel oils,” registered dietician Professor Laurene Boateng from the University of Ghana told The Epoch Times.
She added that unrefined red palm oil has been a staple in many developing countries for ages, even during periods of low chronic disease prevalence, suggesting that the current surge in chronic diseases may be more attributable to the “westernization” of diets rather than the consumption of tropical oils, including red palm oil.
Butter
Butter is widely acknowledged as a nutritious food, especially from pasture-raised animals. It’s rich in essential vitamins such as A, E, D, B12, and K2. K2 vitamins are mainly found in animal products or fermented foods. Additionally, butter contains beneficial amounts of sodium, calcium, and phosphorus.
Butter is rich in butyric acid, a fatty acid produced by good bacteria in the gut when they break down dietary fiber. It supports gut health, helps prevent inflammatory gut diseases, and helps alleviate constipation.
Regular butter has a smoke point of 350 F or 177 C, suitable for low- to medium-heat cooking and baking. For high-heat cooking, clarified butter or ghee is recommended.
Ghee has a higher smoke point of 482 F or around 250 C. People who are lactose intolerant can use ghee for cooking, as the clarification process removes dairy proteins and sugars, including lactose.
Tallow
Tallow, derived from beef or lamb fat, boasts a high smoke point of 400 F or 205 C (though some experts say it is higher), making it ideal for medium- to high-heat cooking.
Organic, pasture-raised tallow typically has a beneficial omega-3 to omega-6 ratio of around 1:2. However, tallow from grain-fed ruminants may have a higher omega-6 content.
Tallow’s abundance of saturated and monounsaturated fats helps protect against omega-3 fatty acid degradation that may occur during cooking.
Tallow is a good source of arachidonic acid, an essential omega-6 fatty acid the body uses to produce endocannabinoids, neurotransmitters essential for reducing anxiety. Additionally, pasture-raised tallow is rich in fat-soluble vitamins A, D, E, K1, and B1. Nutritional levels may vary depending on the ruminant’s diet.
Refined Versus Unrefined
The health effects of the refinement process used in oils are still uncertain, and some doctors have expressed concerns about the refinement process introducing toxins into the body. However, most research has focused on polyunsaturated vegetable oils such as canola and soybean rather than saturated fats.
Vegetable oils are typically deodorized to remove rancid scents. But, according to research, this can result in the formation (pdf) of trans unsaturated fats, which are considered the most harmful fats to consume, as well as glycidol, a known carcinogen (pdf).
Animal fats can also undergo hydrogenation, leading to the production of trans fats in the final product. While lard and tallow primarily consist of saturated fats, they contain some polyunsaturated fats that can be hydrogenated to enhance the solidity and shelf life of the product.
Where Do Other Oils Fit In?
Sesame oil is a versatile cooking oil with diverse applications. Traditional sesame seed oils, derived from roasted sesame seeds, have a long history in Asian cuisines. The roasting process unlocks unique sesame antioxidants like sesamol and sesaminol, which help extend the oil’s shelf life.
Vegetable oils rich in monounsaturated fats, such as olive and avocado, are commonly recommended for low-heat cooking. However, there is an ongoing debate about their suitability for high-heat cooking and frying. Some studies suggest that extra-virgin olive and avocado oils are less stable, while others indicate they are the most stable and oxidation-resistant.
Olive oil has a historical culinary significance, while avocado oil emerged more recently in New Zealand in the early 2000s (pdf). However, despite their high smoke points, both oils, especially with their high monounsaturated fat content, are more prone to oxidation than animal and vegetable oils rich in saturated fats.
.png)
Comments
Post a Comment