The Truth About Fats: Why Animal Fat is Healthier Than You Think and Seed Oils Might Be Killing You

We grew up in the generation of low fat diets. It seems odd now with carnivore and keto diets all the rage, but for years fats and carbs were vilified across both media and the consensus across the medical/nutritional field was that fat was bad for you. The narrative pushed by many health organizations and experts was straightforward: saturated fats or “animal fats,” were the primary culprits in heart disease and obesity, while unsaturated fats, particularly from seed oils, were promoted as healthier alternatives. However, recent research and deeper investigations into the science of fats suggest that this narrative may have oversimplified the complex roles that different types of fats play in our health.

In fact, many nutritionists and researchers are beginning to challenge the long-held belief that saturated fats are harmful and that seed oils are beneficial.

Understanding Fats: Saturated vs. Unsaturated

“To understand the ongoing debate, we need to first understand the difference and what saturated and unsaturated fats are on a chemical level.

- Saturated fats are fats in which the carbon atoms are fully “saturated” with hydrogen, meaning there are no double bonds between carbon atoms. This gives them a solid structure at room temperature. Animal-based fats like butter, lard, tallow, and fats from meats are high in saturated fat. Certain tropical oils, like coconut oil and palm oil, also contain significant amounts of saturated fat.

- Unsaturated fats contain one or more double bonds between carbon atoms. These double bonds create kinks (bends, not the sexy kind of kink…) in the fatty acid chains, making them liquid at room temperature. Unsaturated fats are often divided into monounsaturated (one double bond) and polyunsaturated fats (multiple double bonds). Polyunsaturated fats are found in vegetable oils like soybean, corn, canola, and sunflower oil, often collectively referred to as "seed oils."

The Demonization of Saturated Fats: Where Did It All Go Wrong?

The idea that saturated fats are dangerous comes largely from studies conducted in the mid-20th century, such as the influential **Seven Countries Study** by Ancel Keys. This study suggested a correlation between saturated fat intake and heart disease, which led to the widespread adoption of low-fat diets. Saturated fats were quickly labeled as the enemy of heart health, contributing to increased cholesterol levels and cardiovascular disease.

(it’s important to note that cholesterol and even high cholesterol isn’t inherently harmful, but we’ll explain further down.)

Recent research has raised questions about these conclusions. One of the major criticisms of the Seven Countries Study was its selective data interpretation, excluding countries that didn’t fit the hypothesis, such as France, where people consume high levels of saturated fat but have relatively low rates of heart disease (a phenomenon now known as the French Paradox).

In fact, **several large-scale meta-analyses**, including a notable 2010 study published in the *American Journal of Clinical Nutrition*, found no significant evidence to support the idea that saturated fat intake is directly associated with an increased risk of coronary heart disease. Additionally, in 2017, a comprehensive review published in the British Medical Journal concluded that replacing saturated fats with polyunsaturated fats has not significantly improved heart health as once thought.

Rethinking Cholesterol: Why High Cholesterol May Not Always Be a Bad Thing:

I’ve recently had a friend dealing with high cholesterol who has been off and on medications and trying all sorts of fad diets so I wanted to include an aside on cholesterol as much of the reasoning behind their dieting has been a negative outlook on things like bacon, butter, and steak.

For many years, cholesterol has been portrayed as the primary villain in the battle against heart disease. High levels of cholesterol, particularly LDL cholesterol, were seen as a major risk factor for cardiovascular issues, leading to widespread use of cholesterol-lowering medications like statins. However, recent research challenges the simplicity of this narrative. It turns out that cholesterol is not inherently harmful; in fact, it’s vital for various bodily functions, such as building cell membranes, producing hormones, and aiding in the absorption of fat-soluble vitamins. Studies have shown that high cholesterol levels, particularly in older adults, do not necessarily correlate with an increased risk of heart disease and may even be associated with greater longevity in certain populations.

For example, a 2016 meta-analysis published in BMJ Open reviewed 19 studies and found an inverse association between high LDL cholesterol and mortality in older populations, with researchers stating, "Our findings provide the rationale for a re-evaluation of the guidelines recommending lowering cholesterol in the elderly" . Additionally, the Japanese Lipid Intervention Trial (J-LIT) followed 47,000 patients and observed that those with higher cholesterol had lower mortality rates, particularly among older adults . This suggests that cholesterol levels alone are not sufficient indicators of cardiovascular risk, especially as we age.

Other factors, such as inflammation, play a far more significant role in heart disease - inflammation that is often caused by linoleic acid found in seed oils. For instance, the Minnesota Coronary Experiment (rediscovered in 2016) showed that while participants who replaced saturated fats with polyunsaturated fats saw cholesterol reductions, this did not translate into lower mortality from heart disease, raising doubts about the value of aggressively lowering cholesterol . The landmark Framingham Heart Study also showed that about half of the people who developed heart disease had “normal” cholesterol levels, emphasizing the importance of looking beyond cholesterol to factors like inflammation, blood pressure, and insulin resistance .

Given these findings, the focus should shift from solely targeting cholesterol levels to considering multiple markers of health, such as triglycerides, HDL cholesterol, blood sugar, and inflammatory markers, for a more comprehensive assessment of cardiovascular risk. By understanding cholesterol in this more nuanced way, we can avoid oversimplifying its role in disease and make smarter decisions about our diet and lifestyle.

The Benefits of Saturated Fats

So, if saturated fats and cholesterol aren’t the villain they’ve been made out to be, what role do they play in a healthy diet? Here are some of the key benefits of saturated fats:

1. Stable and Safe for Cooking

Saturated fats are much more stable than unsaturated fats because they don’t contain double bonds that are susceptible to oxidation when exposed to heat, light, or air. This makes saturated fats ideal for cooking at high temperatures, as they don’t break down into harmful byproducts like some unsaturated oils do. Butter, ghee, and coconut oil are excellent choices for sautéing, frying, or baking.

2. Essential for Brain Health

The human brain is made up of about 60% fat, and saturated fats play a crucial role in maintaining brain structure and function. These fats help form the myelin sheath, which insulates nerve fibers and allows for efficient communication between neurons. Studies suggest that a diet rich in healthy fats, including saturated fats, is important for cognitive function and may help prevent neurodegenerative diseases.

3. Hormone Production

Cholesterol, often feared as a dietary bogeyman, is essential for the production of hormones such as testosterone, estrogen, and cortisol. Saturated fats support healthy cholesterol levels and, by extension, help maintain hormonal balance, which is crucial for everything from mood regulation to reproductive health.

4. Immune Function

Certain types of saturated fats, such as lauric acid (found in coconut oil), have antimicrobial properties and can help strengthen the immune system by fighting off harmful pathogens like bacteria, viruses, and fungi.

The Problem with Seed Oils: Hidden Dangers of Unsaturated Fats

While saturated fats have been unfairly demonized, industrial seed oils—like canola, soybean, and sunflower oil—have been widely embraced as “heart-healthy” alternatives. However, emerging research suggests that these oils may be doing more harm than good.

1. Highly Processed

Seed oils are extracted from seeds through industrial processes that often involve high heat, chemical solvents, and deodorization to make them suitable for consumption. This heavy processing can degrade the oil and produce harmful compounds, such as trans fats, even if the product label doesn’t list them

2. High in Omega-6 Fatty Acids

While omega-6 fatty acids (linoleic acid mentioned earlier) are essential in small amounts, most seed oils contain them in large quantities. Modern diets, particularly in Western countries, are disproportionately high in omega-6 fats compared to omega-3 fats, leading to an imbalanced ratio. This imbalance has been linked to **chronic inflammation**, which is a key factor in the development of heart disease, cancer, diabetes, and autoimmune disorders.

3. Prone to Oxidation

Polyunsaturated fats, like those found in seed oils, are highly susceptible to oxidation when exposed to heat and light. Oxidized fats produce **free radicals**, which can damage cells and tissues, contributing to chronic diseases and premature aging. When cooking with these oils at high temperatures, the risk of producing harmful oxidative byproducts increases.

4. Potentially Linked to Obesity and Metabolic Dysfunction

Some studies suggest that the rise in consumption of seed oils over the past few decades may be correlated with increased rates of obesity and metabolic syndrome. The processed nature of seed oils, combined with their ability to disrupt the body’s normal fat metabolism, may be contributing to weight gain and insulin resistance.

How to Balance Fats in Your Diet for Optimal Health

Given the potential risks associated with seed oils and the benefits of saturated fats, how should you approach fats in your diet? Here are some practical tips:

- Prioritize Natural Fats: Focus on whole food sources of fat, such as grass-fed butter, pasture-raised meats, eggs, coconut oil, and full-fat dairy. These natural fats provide essential nutrients and are less processed than industrial oils.

- Limit Seed Oils: Try to minimize your intake of highly processed vegetable and seed oils, especially in processed foods and restaurant meals. Opt for healthier cooking fats like olive oil, avocado oil, and ghee.

- Balance Omega-6 and Omega-3 Intake: To reduce inflammation and support overall health, aim to balance your intake of omega-6 fats (found in seed oils and processed foods) with omega-3 fats (found in fatty fish, flaxseeds, and chia seeds). Reducing your consumption of seed oils can help restore a healthier balance.

At the end of the day quality matters, if your only source of saturated fats is from feedlot beef, low quality butter or other products you may be doing yourself more harm than good. However, as with most things, it comes down to moderation. Neither saturated nor unsaturated fats are truly “evil” as they often get portrayed in the media, but both are necessary to sustain a well balanced diet. However, it’s fair to say that most of us are getting far too many seed oils in our diet if we’re not paying attention to what we’re eating.

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