Cholesterol

What is cholesterol?

According to the American Heart Association website (AHA, 2017), cholesterol is a waxy substance that comes from two sources: your body and food (para. 3-4). According to the Third report of the National Cholesterol Education Program (NCEP) “cholesterol is a fat-like substance (lipid) that is present in cell membranes and is a precursor of bile acids and steroid hormones” (2002, p. 3163). Cholesterol is produced within the liver, of both man and animal and cholesterol is found in all sources of animal products to include meat and dairy products such as milk and cheese, as well as eggs, fish, and poultry among other sources of animal products (AHA, 2017; U. S. Department of Health and Human Services and the U.S. Department of Agriculture [HHS & USDA], 2015).

In fact, according to the HHS and USDA (2015) the 2015 – 2020 United States Dietary guidelines for Americans states “the body uses cholesterol for physiological and structural functions but makes more than enough for these purposes. Therefore, people do not need to obtain cholesterol through foods” (p. 32). According to the Institute of Medicine (IOM, 2002), any incremental increase above zero of cholesterol, saturated fat, and trans fat increase the risk of developing coronary heart disease by increasing cholesterol levels (p. 542, p. 422, p. 432). According to the AHA (2017) you can ingest cholesterol through the consumption of animal-based foods in the diet and your liver also produces more cholesterol when the foods consumed contain both saturated and trans fat (para. 5).

Where does dietary cholesterol come from?

According to the United States Department of Health and Human Services (HHS) and the United States Department of Agriculture (USDA) (2015) “Dietary cholesterol is found only in animal foods such as egg yolk, dairy products, shellfish, meats, and poultry. A few foods, notably egg yolks and some shellfish, are higher in dietary cholesterol but not saturated fats” (p. 34). According to the American Heart Association (AHA), cholesterol is only found in foods of animal sources and animal products such as dairy products (2017 a).

What is cholesterol for?

According to the HHS & USDA (2015) “The body uses cholesterol for physiological and structural functions but makes more than enough for these purposes” (p. 32). The AHA (2017 a) echo’s this statement by stating that our liver produces all the cholesterol we need (para. 1).

If the body makes more than enough, do we need to consume cholesterol?

No, we do not need to consume cholesterol. According to the HHS and USDA (2015), “People do not need to obtain cholesterol through foods” (p. 32).

The previous 2010 guidelines recommended consuming 300mg of cholesterol per day. The 2015 dietary guidelines recommend consuming as little cholesterol as possible, why has the limit changed?

According to the HHS & USDA (2015):

The Key Recommendation from the 2010 Dietary Guidelines to limit consumption of dietary cholesterol to 300 mg per day is not included in the 2015 edition, but this change does not suggest that dietary cholesterol is no longer important to consider when building healthy eating patterns. As recommended by the IOM, individuals should eat as little dietary cholesterol as possible while consuming a healthy eating pattern (p. 32).

The 2015 dietary guidelines removed the previous recommendation of consuming 300mg of cholesterol per day and now recommend 0mg of cholesterol consumption per day. These guidelines now recognize that there is no safe level of cholesterol consumption. The 2015-2020 guidelines now recognize the importance of dietary cholesterol as a risk factor in the development of coronary heart disease, thus, the guidelines recommend consuming as little dietary cholesterol as possible.

Do the dietary guidelines state that eating any amount of cholesterol increases the risk of heart disease?

While the dietary guidelines do not explicitly state that eating any level of cholesterol (or levels above zero) increases the risk of cardiovascular disease, many studies do indicate it does. The HHS & USDA (2015) do not explicitly inform the public that increased risks exist above zero mg of cholesterol consumption, however the guidelines refer to the IOM report which states to eat as little as possible (p. 32). The HHS & USDA (2015) also state that “strong evidence shows that healthy eating patterns are associated with a reduced risk of cardiovascular disease” (p. 17).

Multiple studies suggest that cholesterol consumed through diet may not elevate total serum cholesterol levels within the human body, however high intake of cholesterol is associated with increased levels of low-density lipoprotein (LDL) oxidation which increases the risk of cardiovascular disease (Hopkins, 1992; Howell, McNamara, Tosca, Smith, & Gaines, 1997; Spence, Jenkins, & Davignon, 2010).

Are there foods that do not contain cholesterol?

Not all foods contain cholesterol. Only animal-based foods contain cholesterol. Cholesterol is produced in the liver of both animals and humans. According to the HHS & USDA “plant foods, such as grains, vegetables, fruits, nuts and seeds as well as vegetable oils do not contain dietary cholesterol” (p. 90).

How much cholesterol should I consume on a daily basis?

The HHS & USDA (2015) stated that, “adequate evidence is not available for a quantitative limit for dietary cholesterol specific to the Dietary Guidelines” (p. 34). However, according to the most highly regarded medical body in the United States, the Institute of Medicine (IOM) (2002), an upper daily limit of cholesterol could not be assigned as there is no safe limit of cholesterol consumption due to the increased risk of cardiovascular disease (p. 103).

The Dietary guidelines refer to the Institute of Medicine for the amount of cholesterol we should consume daily. What does the IOM report state?

According to the IOM (2002), “The report doesn’t set maximum levels for saturated fat, cholesterol, or trans fatty acids, as increased risk exists at levels above zero, however the recommendation is to eat as little as possible while consuming a diet adequate in important other essential nutrients” (para. 8). The IOM (2002) also states “a Tolerable Upper Intake Level is not set for cholesterol because any incremental increase in cholesterol intake increase CHD risk” (p. 542).

Getting your cholesterol levels checked?

If your physician requests you complete a blood cholesterol, or blood lipoprotein, panel this is typically done in the morning after a 9 to 12 hour fast (National Institutes of Health, & National Heart, Lung, and Blood Institute, 2001). This test directly measures the type and amount of combined fat and protein passing through your bloodstream. The National Cholesterol Education Program (NCEP, 2002) acknowledges the “three major classes of lipoproteins are found in the serum of a fasting individual: Low Density Lipoproteins (LDL), High Density Lipoproteins (HDL), and Very Low Density Lipoproteins (VLDL) (p. 3163).

What is LDL Cholesterol?

LDL cholesterol is the number one concern of most physicians and health care providers. LDL cholesterol makes up approximately 60-70 percent of an individual’s cholesterol level and is the main contributing factor to the development of atherosclerotic plaque buildup within arterial walls and is the primary focus of cholesterol lowering therapy, as a reduction in LDL cholesterol lowers the risk of CHD (NCEP, 2002, p. 3163). Multiple studies have shown that as LDL levels increase so does the risk of CHD. According to NCEP (2002), this is due to “the positive relationship between serum cholesterol levels and the development of first or subsequent attacks of CHD is observed over a broad range of LDL-cholesterol levels; the higher the level, the greater the risk” (p. 3164). This is the primary focus in blood cholesterol control.

What is HDL Cholesterol?

HDL cholesterol makes up approximately 20-30 percent of an individual’s cholesterol levels and have been shown to have protective benefits in regards to the development of Atherosclerosis (NCEP, 2002, p. 3163).

What is VLDL Cholesterol?

VLDL cholesterol makes up approximately 10-15 percent of an individual’s cholesterol levels and “are triglyceride-rich lipoproteins” (NCEP, 2002, p. 3163).

What are currently acceptable Blood cholesterol results?

Total Cholesterol

Total Cholesterol (mg/dL)
mg/dL	Risk Level
<200 mg/dL	Desirable
200– 239mg/dL	Borderline High
>240 mg/dL	High

Low Density Lipoprotein (LDL) Cholesterol mg/dL
mg/dL	Risk Level
<100 mg/dL (with an optional goal of <70 mg/dL)	Optimal
100-129 mg/dL	Near Optimal/above Optimal
130-159 mg/dL	Borderline High
160-189 mg/dL	High
>190 mg/dL	Very High

High Density Lipoprotein (HDL) Cholesterol mg/dL
mg/dL	Risk Level
<40 mg/dL	Higher risk
>60 mg/dL	Lower risk

Figure 1. NCEP. (2001). Above images recreated based upon NCEP 9-12 hour fasting recommendations for ATP III Classification of LDL, Total, and HDL Cholesterol (mg/dL). Retrieved October 3, 2016.

Cholesterol levels less than 200mg/dL are deemed acceptable. However, researchers have uncovered that having a total cholesterol lower than 150 may actually be more advantageous. According to Castelli (2001), director of the Framingham heart study, during the first 50 years of Framingham heart study only 5 individuals developed coronary artery disease with a total cholesterol level less than 150 mg/dl (p. 16F). Therefore, the goal should be to decrease total cholesterol to under 150 mg/dl which is actually more desirable, and beneficial to all patients with or without cardiovascular disease.

Dr. Jimmy Conway – Focus On The Food

Cardiovascular disease and Cholesterol: The connection between LDL cholesterol and cardiovascular disease.

Understanding how to manage cholesterol levels and reduce the risk of developing and even potentially reversing the risk of cardiovascular disease is the primary goal of Interventional Cardiologist Dr. Kevin Fullin. Heart disease is a preventable chronic disease which has its roots in nutrition. Changing the food you eat can have great implications on the progression of cardiovascular disease.

Eating You Alive – Dr. Esselstyn “Coronary Heart Disease”

The current recommendations according to National Cholesterol Education Program (NCEP, 2002) recommend a total cholesterol level under 200mg/dL to be desirable (p. 3167).

However, according to Javed et al. (2010), a study of 65,396 individuals administered to the hospital with acute coronary syndrome had an average total blood cholesterol of 170.1 and an average LDL cholesterol of 103.4 (p. 1132). Therefore a cholesterol level lower than 200mg/dL, between 150 to 200mg/dl, while currently considered desirable may not provide individuals with cardiovascular disease prevention and may not reduce the risk of cardiovascular disease in all individuals. According to Castelli (2001) “instead, 35% of all cases or coronary artery disease occur in people whose serum total-cholesterol level is between 150 and 200mg/dl” (p. 16F). Having a cholesterol level lower than 200mg/dL, may not decrease the risk of cardiovascular disease in all patients. Therefore a lower cholesterol level under 150mg/dL is recommended for all patients with cardiovascular disease.

According to William Castelli (2001), director of the Framingham heart study, during the first 50 years of Framingham heart study only 5 individuals developed coronary artery disease with a total cholesterol level less than 150 mg/dL (p. 16F). Therefore, the goal should be to decrease total cholesterol in the blood to under 150mg/dl as this is actually more desirable, and beneficial to patients with cardiovascular disease.

Cholesterol overview:

Based on the above information, the human body has no need for dietary cholesterol as it produces sufficient quantities. The only source of dietary cholesterol within the human diet comes from the ingestion of animal flesh and animal products. Nothing else in the human diet contains cholesterol. Any cholesterol consumption above zero increases the risk of cardiovascular disease. Therefore, abstaining from all animal flesh and animal products decreases the risk of developing cardiovascular disease. Moderate or high consumption of animal flesh or animal products that contain cholesterol is not encouraged due to increased risk of developing heart disease.