Fats: the good, the bad and the ugly! pt 2 - Cholesterol

Grateful to be here today. I hope this finds all of you well. Today I will be taking a closer look at Cholesterol. Is it bad?

So, what is cholesterol?

Cholesterol is a waxy steroid metabolite found in the cell membranes and transported in the blood plasma of all animals. It is an essential structural component of mammalian cell membranes, where it is required to establish proper membrane permeability and fluidity. So it is essentially found in all animal life.

In addition, cholesterol is an important component for the manufacture of bile acids, steroid hormones, and Vitamin D. Cholesterol is the principal sterol synthesized by animals, but small quantities are synthesized in other eukaryotes, such as plants and fungi. It is almost completely absent among prokaryotes, which include bacteria.

Although cholesterol is an important and necessary molecule for animals, a high level of serum cholesterol is an indicator for diseases such as heart disease.

Since cholesterol is essential for all animal life, it is primarily synthesized from simpler substances within the body. However, high levels in blood circulation, depending on how it is transported within lipoproteins, are strongly associated with progression of atherosclerosis.

The body compensates for cholesterol intake by reducing the amount synthesized. So the more cholesterol taken into the body, the less cholesterol the body makes or synthesizes.

Cholesterol is recycled. It is excreted by the liver via the bile into the digestive tract. Typically about 50% of the excreted cholesterol is reabsorbed by the small bowel back into the bloodstream. Phytosterols can compete with cholesterol reabsorption in the intestinal tract, thus reducing cholesterol reabsorption. (see more on Phytosterols and vascular disease)

Where do we get Cholesterol from?

Animal fats are complex mixtures of triglycerides, with lesser amounts of phospholipids and cholesterol. As a consequence, all foods containing animal fat contain cholesterol to varying extents. Major dietary sources of cholesterol include cheese, egg yolks, beef, pork, poultry, and shrimp. (Cholesterol content of selected foods per common measure)

Total fat intake, especially saturated fat and trans fat, (Train Off the Track: Trans Fatty Acids vs. Other Fats) plays a larger role in blood cholesterol than intake of cholesterol itself. Saturated fat is present in full fat dairy products, animal fats, several types of oil and chocolate. Trans fats are typically derived from the partial hydrogenation of unsaturated fats, and do not occur in significant amounts in nature. Trans fat is most often encountered in margarine and hydrogenated vegetable fat, and consequently in many fast foods, snack foods, and fried or baked goods.

Types of cholesterol

There are several kinds, but the most important are Low-Density Lipoprotein (LDL or ‘bad’) and High-Density Lipoprotein (HDL or ‘good’).

LDL (Bad) Cholesterol
When too much LDL (bad) cholesterol circulates in the blood, it can slowly build up in the inner walls of the arteries that feed the heart and brain. Together with other substances, it can form plaque, a thick, hard deposit that can narrow the arteries and make them less flexible. This condition is known as atherosclerosis. If a clot forms and blocks a narrowed artery, heart attack or stroke can result.

HDL (Good) Cholesterol
About one-fourth to one-third of blood cholesterol is carried by high-density lipoprotein (HDL). HDL cholesterol is known as "good" cholesterol, because high levels of HDL seem to protect against heart attack. Low levels of HDL (less than 40 mg/dL) also increase the risk of heart disease. Medical experts think that HDL tends to carry cholesterol away from the arteries and back to the liver, where it's passed from the body. Some experts believe that HDL removes excess cholesterol from arterial plaque, slowing its buildup. (Good vs Bad cholesterol)



How do you reduce "bad" cholesterol?

The amount of cholesterol present in plant-based food sources is generally much lower than animal based sources. In addition, plant products such as flax seeds and peanuts contain cholesterol-like compounds called phytosterols, which are suggested to help lower serum cholesterol levels.(See more here)

A change in diet in addition to other lifestyle modifications may help reduce blood cholesterol. Avoiding animal products may decrease the cholesterol levels in the body not only by reducing the quantity of cholesterol consumed but also by reducing the quantity of cholesterol synthesized. Those wishing to reduce their cholesterol through a change in diet should aim to consume less than 7% of their daily calories from saturated fat and fewer than 200 mg of cholesterol per day.(Dietary guidelines for Americans)


So lifestyle change is crucial in lowering risks involved with High choelsterol. Exercising and making it a regular part of life is an important lifestyle in addition to modifying the diet. the ideal diet is a vegetarian diet in combination with exercise. This lifestyle eliminates the intake of cholesterol from animal sources primarily meat but also the active lifestyle helps in lowering excess cholesterol in circulation.