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Spacefill model of the Cholesterol molecule

Reviewed by  Dr. Damigo; PhD

Why do people on cholesterol-lowering drugs still have heart attacks?
What role does cholesterol really play?
How can you lower your risk of heart disease and stroke?  

What to Do About High Cholesterol answers these questions and explains why lowering your LDLs (the bad cholesterol) is even more important than previously thought.

From food to cholesterol

As you eat, your intestine absorbs fat from food. Intestinal enzymes rapidly dismantle the long, complex fat molecules into their component fatty acids, reassemble them into new triglyceride molecules, and package these—along with a small amount of cholesterol—into chylomicrons (see Figure 2). The amount of triglyceride-rich particles in the blood increases for several hours after a meal, as the intestine releases a barrage of chylomicrons filled with triglycerides. That is why you’re asked to fast before going in for a cholesterol test that measures the different lipids in your blood. If you don’t, the triglyceride amounts appear higher than usual, which skews the readings of the other lipids as well.

Figure 2: How food becomes cholesterol

At the same time, dietary carbohydrates and proteins that are absorbed from the intestine pass to the liver, which converts them to triglyceride molecules, packages them with proteins called apolipoproteins and cholesterol, and releases the resulting VLDLs into the bloodstream. As chylomicrons and VLDLs course around the body, they temporarily stick to the walls of blood vessels in muscle tissue that needs energy or in fatty tissue (adipose tissue) that stores energy. Enzymes come along and remove most of their load of triglyceride molecules, which are then transported inside the muscle or fat cells. As triglyceride is drained from the chylomicron or VLDL particles, their protective protein coats are rearranged and reconfigured, essentially giving them a new address label that can be read by the liver or other tissues that take up lipoproteins.

What to do About High Cholesterol

The report includes a step-by-step method to determine your risk level for heart disease and specific guidelines on how to lower your risk.
Prepared by the editors of Harvard Health Publications in consultation with Mason Freeman, M.D., associate professor of medicine, Harvard Medical School and Chief of the Lipids Metabolism Unit at Massachusetts General Hospital. 48 pages. (2009)

  • Cholesterol in the body
    • HDLs, LDLs, and other lipid particles
    • From food to cholesterol
  • The cholesterol connection
    • The role of diet
    • The role of inflammation
    • From cholesterol to heart attack or stroke
  • What causes heart disease
    • Risk factors for heart disease
    • Metabolic syndrome
    • Protective factors
    • For women: Hormone therapy
    • Weighing the risk factors
  • Why treat cholesterol?
    • Benefits of lowering your cholesterol
    • What are the risks of treatment?
    • Is treatment worth the trouble or the cost?
  • Your cholesterol test
    • When to test
    • Taking the test
    • Understanding your test results
    • Physical examination and further tests
  • Do you need treatment?
    • Seven-step assessment
    • How low can you go?
  • Beginning treatment
    • Pinpoint the cause
    • Start your program
    • Adopt a cholesterol-lowering diet
    • Start an exercise program
  • Drugs, herbs and other choices for lowering-cholesterol
  • Treating other lipid problems
    • What to do about low HDL
    • How to treat high triglycerides
  • Taking an individual approach
    • Cholesterol in racial and ethnic groups
    • Cholesterol in people who have heart disease
    • Cholesterol in people who have diabetes
    • Cholesterol in people with chronic kidney disease
    • Cholesterol in women
    • Cholesterol in the elderly
  • Resources
  • Glossary

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