Cholestrol | Zoology Optional Notes for UPSC PDF Download

What is cholesterol?

• Cholesterol is a waxy substance present in all body cells, necessary for making hormones, vitamin D, and digestion aids.
• The body produces all the cholesterol it needs.
• Cholesterol is also ingested from animal-based foods like egg yolks, meat, and cheese.
• Excess cholesterol in the blood can form plaque by combining with other substances, adhering to artery walls.
• This plaque buildup, called atherosclerosis, can cause coronary artery disease by narrowing or blocking coronary arteries.

What are HDL, LDL, and VLDL?

• Lipoproteins: Combination of fat (lipid) and protein, necessary for transporting lipids through the blood.
• HDL (High-Density Lipoprotein):
  • Often referred to as "good" cholesterol.
  • Transports cholesterol from the body back to the liver for removal.
• LDL (Low-Density Lipoprotein):
  • Known as "bad" cholesterol due to its role in plaque buildup within arteries.
• VLDL (Very Low-Density Lipoprotein):
  • Also considered a type of "bad" cholesterol for its contribution to arterial plaque.
  • Mainly transports triglycerides, unlike LDL, which primarily carries cholesterol.

What causes high cholesterol?

Unhealthy Lifestyle Causes:

• Unhealthy Eating Habits: Consumption of bad fats, like saturated fat (found in meats, dairy, chocolate, baked goods, deep-fried and processed foods) and trans fat (found in some fried and processed foods), raises LDL cholesterol.
• Lack of Physical Activity: Minimal exercise and excessive sitting reduce HDL cholesterol.
• Smoking: Lowers HDL cholesterol, particularly in women, and increases LDL cholesterol.

Genetics and Medical Conditions:

• Genetics: Conditions like familial hypercholesterolemia (FH) demonstrate inherited high cholesterol.
• Medical Conditions and Medicines: Certain health issues and medications can elevate cholesterol levels.

What can raise my risk of high cholesterol?

Risk Factors for High Cholesterol:

• Age:
  • Cholesterol levels generally increase with age.
  • High cholesterol is not exclusive to adults; children and teens can also be affected.
• Heredity: High blood cholesterol can be familial.
• Weight: Being overweight or obese contributes to higher cholesterol levels.
• Race: Certain races, such as African Americans, may have a higher risk, often showing higher HDL and LDL cholesterol levels compared to whites.

What health problems can high cholesterol cause?

Plaque and Arteries:

• Large plaque deposits in arteries can lead to rupture, causing blood clots on the plaque surface.
• A large clot can significantly reduce or block blood flow in a coronary artery.

Consequences of Reduced Blood Flow:

• Reduced or blocked oxygen-rich blood flow to the heart can result in angina (chest pain) or a heart attack.

Plaque in Other Arteries:

• Plaque buildup isn't limited to coronary arteries; it can also occur in arteries supplying blood to the brain and limbs.
• This can lead to carotid artery disease, stroke, and peripheral arterial disease.

How is high cholesterol diagnosed?

High Cholesterol Signs and Testing:

• Typically, there are no signs or symptoms of high cholesterol.
• Cholesterol levels are measured through a blood test.

Testing Recommendations by Age:

Ages 19 or Younger:

• Initial test between ages 9 to 11.
• Retest every 5 years.
• Testing may start at age 2 for those with a family history of high blood cholesterol, heart attack, or stroke.

Age 20 or Older:

• Young adults should be tested every 5 years.
• Men aged 45 to 65 and women aged 55 to 65 should have the test every 1 to 2 years.

How can I lower my cholesterol?

Lowering Cholesterol with Lifestyle Changes:

• Adopt a heart-healthy eating plan.
• Manage weight effectively.
• Engage in regular physical activity.

Medications for Lowering Cholesterol:

• If lifestyle changes are insufficient, medication, such as statins, may be necessary.
• Continue lifestyle changes even when taking medication to lower cholesterol.

Special Treatments for Familial Hypercholesterolemia (FH):

• Lipoprotein apheresis may be used, involving a filtering machine to remove LDL cholesterol from the blood, then returning the filtered blood back to the person.