7 Common Myths About Dietary Fat and Cholesterol

For decades, people have avoided fat and cholesterol rich foods, such as butter, nuts, egg yolks, and full fat dairy, instead opting for low fat substitutes like margarine, egg whites, and fat-free dairy in hopes of bettering their health and losing weight.

This is due to the misconception that eating foods rich in cholesterol and fat may increase your risk of various diseases.

While recent research has disproven this notion, myths surrounding dietary cholesterol and fat continue to dominate headlines, and many healthcare providers continue to recommend very low-fat diets to the general public.

Here are 7 common myths about dietary fat and cholesterol that should be put to rest

1. Eating fat leads to weight gain 

A common diet myth is that eating high fat foods causes you to gain weight.

While it’s true that eating too much of any macronutrient, including fat, makes you gain weight, consuming fat-rich foods as part of a healthy, balanced diet does not lead to weight gain.

On the contrary, consuming fat-rich foods will keep you satisfied between meals, which may help you lose weight.

In fact, numerous studies have shown that eating high fat foods, including whole eggs, avocados and nuts can help boost satiety (the feelings of fullness). (1, 2, 3, 4)

Additionally, dietary patterns that are very high in fat, including ketogenic and low carb, high fat diets, have been shown to promote weight loss. (5, 6, 7)

Of course, quality matters. Therefore, consuming highly processed foods that are rich in fats, such as fast food, sugary baked goods, and fried foods, will increase your risk of weight gain. (8, 9, 10)

2. Cholesterol-rich foods are unhealthy 

Many people assume that cholesterol-rich foods, including whole eggs, shellfish, organ meats, and full-fat dairy, are unhealthy.

Although it’s true that some cholesterol-rich foods, such as ice cream, fried foods, and processed meat, should be limited in any healthy dietary pattern, the majority of us don’t need to avoid nutritious, high cholesterol foods.

In fact, many high cholesterol foods are among the most nutritious foods we can consume.

For example, egg yolks are high in cholesterol and also happen to be loaded with important vitamins and minerals, including B12, choline, and selenium, while high cholesterol full fat yogurt is packed with complete protein and calcium. (11, 12, 13)

Additionally, just 1 ounce of cholesterol-rich, cooked raw liver provides over 50 percent of the Reference Daily Intake (RDI) for copper, vitamins A and B12. (14)

Research has also shown that consuming healthy, cholesterol-rich foods like eggs, fatty seafood, and full fat dairy may improve many aspects of health, which will be covered in this article.

3. Saturated fat causes heart disease 

While the topic is still hotly debated among healthcare professionals, recent research has shown that there is no consistent link between saturated fat intake and heart disease.

While it may be true that saturated fat increases well-known heart disease risk factors, such as LDL (bad) cholesterol and apolipoprotein B. (15)

Saturated fat intake tends to increase the amount of large, fluffy LDL particles, but decrease the amount of smaller, denser LDL particles that are linked to heart disease.

Additionally, research has demonstrated that certain types of saturated fat may increase heart-protective HDL cholesterol. (16)

In fact, numerous large studies have found no consistent association between saturated fat intake and heart disease, heart attack, or heart-disease-related death. (17, 18, 19)

What we need to remember is that there are many types of saturated fats, all with different effects on health.

Therefore, your diet as a whole, rather than the breakdown of your macronutrient intake, is most important when it comes to your overall health and disease risk.

Nutritious foods high in saturated fat like full fat yogurt, grass fed beef, eggs, cheese, and dark cuts of poultry can certainly be included in a healthy, well-rounded diet.

4. Eating fat increases diabetes risk

Many dietary patterns recommended for the treatment of type 2 and gestational diabetes are low in fat. This is due to the misconception that consuming dietary fat may increase the risk of diabetes.

Although consuming certain fat-rich foods, such as trans-fat, fatty baked goods, and fast food, can indeed increase your risk of diabetes, research has shown that other high fat foods may offer protection against its development. (20)

For example, fatty fish, full fat dairy, avocados, coconut oil, and nuts are high fat foods that have all been shown to improve blood sugar and insulin levels and potentially protect against diabetes development. (21, 22, 23, 24)

While some evidence suggests that a greater intake of saturated fat may increase diabetes risk, more recent studies have found no significant association.

For example, a 2019 study in 2,139 people found no association between the consumption of animal and plant-based fat or total fat and the risk of type 2 diabetes. (25)

The most important factor in reducing your diabetes risk is the overall quality of your diet, not the breakdown of your macronutrient intake.

5. Margarine and omega-6-rich oils are healthier   

It’s often thought that consuming vegetable-oil-based products like margarine and canola oil in place of animal fats is better for health. However, based on the results of recent research, this is a misconception.

Margarine and certain vegetable oils, including canola and soybean oil, are high in omega-6 fats. Though both omega-6 and omega-3 fats are needed for health, modern-day diets tend to be much too high in omega-6 fats and too low in omega-3s.

This imbalance between omega-6 and omega-3 fat intake has been linked to increased inflammation and the development of adverse health conditions.

In fact, a higher omega-6 to omega-3 fatty acid ratio has been associated with health conditions like mood disorders, obesity, insulin resistance, increased heart disease risk factors, and mental decline. (26, 27, 28, 29)

Canola oil is used in many vegetable oil blends, butter substitutes, and low fat dressings. Although it’s marketed as a healthy oil, studies show that its intake may have harmful effects on many aspects of health.

For example, studies in humans indicate that canola oil intake may be associated with increased inflammatory response and metabolic syndrome, which is a cluster of conditions that increases heart disease risk. (30, 31)

Additionally, research observes that replacing saturated fat with omega-6 rich fats is unlikely to reduce heart disease and may even increase the risk of heart-disease-related mortality. (32, 33)

6. Everyone responds to dietary cholesterol the same way

Although some genetic and metabolic factors may warrant following a diet lower in saturated fat and cholesterol, for the majority of the population, saturated fat and cholesterol-rich foods can be included as part of a healthy diet.

About two-thirds of the population has minimal to no response to even large amounts of dietary cholesterol and are known as compensators or hypo-responders.

Alternatively, a small percentage of the population is considered hyper-responders or noncompensators, as they are sensitive to dietary cholesterol and experience much larger increases in blood cholesterol after eating cholesterol-rich foods. (34)

However, research shows that, even in hyper-responders, the LDL-to-HDL ratio is maintained after cholesterol intake, meaning that dietary cholesterol is unlikely to lead to changes in blood lipid levels that increase the risk of heart disease progression. (35, 36, 37, 38)

This is due to adaptations that take place in the body, including enhancement of certain cholesterol removal pathways, to excrete excess cholesterol and maintain healthy blood lipid levels.

However, some research has shown that a small percentage of people that have a condition called familial hypercholesterolemia, a genetic disorder that may increase heart disease risk, have a reduced capacity to remove excess cholesterol from the body (39)

As you can see, response to dietary cholesterol is individualized and can be affected by many factors, especially genetics. It’s best to speak with a healthcare professional if you have questions about your ability to tolerate dietary cholesterol and how that may affect your health.

7. Fat-free products are a smart choice 

If you walk around your local supermarket, chances are you’ll spot an abundance of fat-free products, including salad dressings, ice cream, milk, cookies, cheese, and potato chips.

These items are typically marketed to those looking to slash calories from their diet by choosing lower calorie foods.

While low fat foods might seem like a smart choice, these foods aren’t good for overall health. Unlike naturally fat-free foods, such as most fruits and veggies, processed fat-free foods contain ingredients that can negatively affect your body weight, metabolic health, and more.

Despite having fewer calories than their regular-fat counterparts, fat-free foods are typically much higher in added sugar. Consuming high amounts of added sugar has been associated with the progression of chronic conditions like heart disease, obesity, and diabetes. (40)

Additionally, eating foods rich in added sugar may negatively affect certain hormones in your body, including leptin and insulin, causing you to consume more calories in general, which can ultimately lead to weight gain. (41)

What’s more, many fat-free products contain preservatives, artificial food dyes, and other additives that many people prefer to avoid for health reasons. Plus, they’re not as satisfying as foods that contain fat.

Instead of trying to cut calories by choosing highly processed fat-free products, enjoy small amounts of whole, nutritious sources of fats at meals and snacks to promote overall health.

Bottom line

Dietary fat and cholesterol are often vilified by many health professionals, which has led many people to avoid high fat foods.

However, focusing on singular macronutrients rather than your overall diet is problematic and unrealistic.

While it’s true that certain high fat and high cholesterol foods, such as fast food and fried foods, should be restricted in any healthy diet, many nutritious fat-rich foods can and should be included in healthy, well-rounded dietary patterns.

It’s important to note that humans do not consume macronutrients like fats in isolation — they eat foods containing different types and ratios of macronutrients.

For this reason, your over-all diet rather than your consumption of individual macronutrients is the most important factor in disease prevention and health promotion.