Cholesterol and the Carnivore Diet

Many individuals worry about the carnivore diet’s potential to raise cholesterol levels, which have long been linked to a higher risk of coronary heart disease.

A carnivore diet, like other low-carb diets, may raise cholesterol levels, but an increase in cholesterol levels, particularly the “bad” low-density lipoprotein cholesterol (LDL-C), should not necessarily be a cause for concern. LDL-C is an inadequate indicator of cardiovascular disease risk, and the number of LDL particles, particularly the smaller, denser ones, is a better indicator.

Studies also suggest that low-carb diets can increase LDL particle size and decrease the number of small, dense LDL particles, both of which indicate a reduced risk of cardiovascular disease. This post will demonstrate why an increase in cholesterol levels on this diet may not be a worry.

What is Cholesterol?

Cholesterol is a lipid-like substance that is present in blood and every cell of your body.

Your body is capable of producing sufficient cholesterol on its own.

Nevertheless, animal-based foods like meat, fat, eggs, poultry, dairy, and seafood can also provide you with cholesterol.

Unlike animal-based foods, plant-based foods do not contain any cholesterol.

The Role of Cholesterol

Cholesterol plays a crucial role in maintaining human life. Without it, we would not be able to survive.

Cholesterol is a vital part of the cell membrane, providing structural support and regulating its fluidity. Additionally, cholesterol is present in every cell of the body, making it an indispensable component for our survival.

Cholesterol serves as a precursor molecule for the synthesis of vitamin D, steroid hormones, and sex hormones. Additionally, it is a key component of bile salts that aid in the digestion and absorption of fat-soluble vitamins A, D, E, and K.

Moreover, cholesterol plays a crucial role in maintaining proper brain function. As the most cholesterol-rich organ in the body, the brain contains approximately 20% of the body’s total cholesterol.

Measuring Cholesterol

Since cholesterol is not soluble in water, lipoproteins are responsible for transporting it around the body to perform its various functions [5]. Lipoproteins are protein molecules that carry both cholesterol and triglycerides [6].

There are seven types of lipoproteins, but blood tests generally report cholesterol levels in two types: low-density lipoprotein (LDL) and high-density lipoprotein (HDL). In the United States, cholesterol levels are measured in milligrams of cholesterol per deciliter of blood, while in Europe and other countries, they are measured in millimoles per liter.

To ensure that the cholesterol and fat particle levels in the blood are not influenced by recent food intake, fasting for 8 to 12 hours is typically required before cholesterol testing.

LDL

Low-density lipoproteins (LDL) are the primary cholesterol transporters in the body, carrying cholesterol from the liver to various tissues and cells throughout the body.

Medical professionals and literature often refer to LDL as the “bad” cholesterol, as high levels of LDL have been linked to cholesterol buildup in the arteries.

HDL

High-density lipoproteins (HDL) serve the opposite function of LDL by removing excess cholesterol from peripheral tissues and transporting it back to the liver for excretion.

HDL is commonly referred to as the “good” cholesterol because it counteracts the effects of LDL and is believed to reduce the development of plaque in the arteries.

Triglycerides

Along with LDL, HDL, and total cholesterol, triglyceride levels are frequently reported as part of an overall lipid profile [12].

Triglycerides are a type of fat in the blood that can originate from dietary fats or be produced from excess calories consumed [12].

Epidemiological data suggests a link between high triglyceride levels and an elevated risk of metabolic syndrome and cardiovascular disease.

Cholesterol Levels

To sum up, healthcare experts generally believe that maintaining low levels of LDL cholesterol and triglycerides, as well as high levels of HDL cholesterol, is beneficial for your health.

It’s worth noting that the recommended cholesterol levels are based on the typical high-carb and omnivore diets consumed by the general population. As a result, they may not be particularly relevant to those following a carnivore diet.

Assuming these guidelines still hold some value, we’ll examine whether high cholesterol levels on a carnivore diet should be a cause for concern.

From the existing evidence, it appears that individuals who follow a carnivore diet typically have higher total cholesterol, LDL, and HDL levels, while experiencing a reduction in triglyceride levels.

Why Your Cholesterol Could Potentially Increase On The Carnivore Diet

The primary reason for the increase in total cholesterol, HDL, and LDL on the carnivore diet is the shift from using carbohydrates to fats for energy. Since there is a limited amount of carbohydrates in a low-carb or carnivore diet, the liver has to convert a significant amount of fatty acids into ketones for energy use.

When fatty acids enter the liver, they are converted into acetyl-CoA, which can be used for energy or converted to HMG-CoA. Since HMG-CoA is involved in both cholesterol and ketone formation, when in ketosis, both ketone and cholesterol production increase, leading to an increase in total cholesterol, HDL, and LDL.

Additionally, fasting can cause a similar increase in cholesterol levels as the liver begins to break down fatty acids for energy after glycogen stores are depleted. While elevated HDL is considered a positive indicator, an increase in LDL is typically seen as negative due to its association with a higher risk of heart disease, though this may not always be the case, as explained below.

Is High Cholesterol On The Carnivore Diet Even An Issue?

As previously mentioned, cholesterol is a crucial component in the human body, and its absence could result in instant death. This raises the question of why such a vital substance can also be deadly, and whether an elevated LDL cholesterol level on a carnivore diet should be a cause for concern.

The answer is no.

Studies have demonstrated that an increase in LDL cholesterol levels on a low-carb, high-fat diet or the carnivore diet is not necessarily a cause for concern, as the number of LDL particles is a better indicator of the risk of heart disease than LDL cholesterol levels.

Although LDL particle sizes may increase on low-carb, high-fat diets (potentially contributing to the increase in total LDL cholesterol), the total number of LDL particles and small LDL particles actually decrease, which research has shown indicates a reduction in the risk of cardiovascular diseases.

LDL cholesterol vs LDL particle number

LDL cholesterol (LDL-C) is a metric used to determine the quantity of cholesterol present within LDL particles.

LDL particle (LDL-P) number refers to the total number of low-density lipoprotein particles present in your bloodstream.

Despite being a common tool for evaluating cardiovascular risk, LDL cholesterol is frequently estimated rather than directly measured due to financial constraints.

This can lead to issues since (i) LDL particles can differ in size, and (ii) LDL particles may not all carry the same amount of cholesterol.

LDL Particles Is More Indicative of Cardiovascular Disease Risk than LDL Cholesterol

A study conducted on 3066 middle-aged participants (Framingham Offspring Study) measured both LDL cholesterol, non-HDL cholesterol, and LDL particle number. [27]

The study tracked participants for approximately 15 years, recording incidents of cardiovascular disease (CVD).

The findings indicated that LDL particle number was more closely related to the incidence of cardiovascular disease than LDL cholesterol or non-HDL cholesterol levels.

Individuals with a low level of LDL particles (<25th percentile) had a lower CVD event rate (59 events per 1000 person-years) than those with an equivalently low level of LDL cholesterol (81 events per 1000 person-years).

This study highlights that the number of LDL particles is a superior indicator of cardiovascular risk compared to LDL cholesterol alone, and that lower LDL particle numbers are more favorable.

A systematic review by Ravnskov et al (2016) published in the British Medical Journal similarly found a lack of association or an inverse association between LDL cholesterol and mortality in the elderly.

Additionally, LDL particles are not uniform, and small, dense particles are more likely to contribute to the formation of arterial plaque due to their increased entry and retention in the arteries and susceptibility to oxidation. Research indicates that individuals with predominantly small, dense LDL particles have an elevated risk of coronary heart disease, regardless of their overall LDL cholesterol levels. Conversely, those with mostly large LDL particles have a lower risk of developing heart disease.

Low Carb, High Fat Diets Decrease Cardiovascular Disease Risk

The literature review presented above highlights the positive effects of low-carb and high-fat diets on LDL particles. Falkenhain et al (2021) conducted a meta-analysis of 38 randomized trials and found that low-carb diets decreased the number of total and small LDL particles, while increasing LDL particle size. Similarly, Froyen’s (2021) review found that higher fat diets decreased the number of small, dense LDL particles and/or increased the number of large and buoyant LDL particles compared to lower fat diets. These changes indicate a reduced risk of cardiovascular diseases.

Studies have shown that small, dense and oxidized LDL particles are more likely to contribute to plaque formation in the arteries, increasing the risk of cardiovascular diseases. Therefore, a decrease in the number of small LDL particles on a low-carb diet could potentially lower the risk of heart diseases.

In contrast, large LDL particles have been found to not be associated with an increased risk of heart diseases. A study of 2072 men found that large LDL sub-fractions were not linked to an increased risk of CVD events, but small LDL sub-fractions were.

Overall, an increase in LDL particle size on low-carb high-fat diets, which is likely the cause of the increase in LDL cholesterol, indicates a lower risk of heart diseases. Therefore, the number of LDL particles is a better indicator of cardiovascular disease risk than LDL cholesterol level alone.

Conclusion

The carnivore diet and other low-carb diets may result in lower triglyceride levels, higher total cholesterol, HDL and LDL cholesterol levels. While a decrease in triglycerides and an increase in HDL cholesterol are considered positive indicators, an increase in LDL cholesterol has traditionally been viewed as negative because it has been associated with plaque formation in arteries. However, studies suggest that LDL cholesterol level alone is not a good marker of coronary heart disease risk; rather, the number of small, dense LDL particles is a more accurate predictor. These small, dense or oxidized LDL particles promote plaque buildup in arteries. Research indicates that low-carb diets, including the carnivore diet, can decrease the number of small, dense LDL particles, which suggests that they can have a beneficial effect on heart health.