What Is Cholesterol?

What Is Cholesterol?

Cholesterol and Where It Lurks

Burgers. Bacon. Cheese fries. What do they have in common (besides being some people's idea of delicious)? They're all high in cholesterol.

Cholesterol, a waxy substance produced by the liver and found in certain foods, is needed to make vitamin D and some hormones, build cell walls, and create bile salts that help you digest fat. Actually, your liver produces about 1,000 milligrams of cholesterol a day, enough cholesterol so that if you never touched another cheese fry, you'd be OK. But it's hard to avoid cholesterol entirely because so many foods contain it.

Too much cholesterol in the body can lead to serious problems like heart disease. Many factors can contribute to high cholesterol, but the good news is there are things you can do to control them.

Lipids are fats that are found throughout the body. Cholesterol, a type of lipid, is found in foods from animal sources. This means that eggs, meats, and whole-fat dairy products (including milk, cheese, and ice cream) are loaded with cholesterol — and vegetables, fruits, and grains contain none.

Besides the 1,000 milligrams of cholesterol that your liver produces each day, you probably consume about 150 to 250 milligrams in the foods you eat.

Because cholesterol can't travel alone through the bloodstream, it has to combine with certain proteins. These proteins act like trucks, picking up the cholesterol and transporting it to different parts of the body. When this happens, the cholesterol and protein form a lipoprotein together.

The two most important types of lipoproteins are high-density lipoproteins (or HDL) and low-density lipoproteins (or LDL). You've probably heard people call LDL cholesterol "bad cholesterol" and HDL cholesterol "good cholesterol" because of their very different effects on the body:

Dangers of High Cholesterol

When you have too much cholesterol, it can be dangerous to your health. When LDL cholesterol levels are high, cholesterol is deposited on the walls of arteries and forms a hard substance called plaque. Over time, plaque causes the arteries to become narrower, decreasing blood flow and causing a condition called atherosclerosis (pronounced: ah-thuh-ro-skluh-RO-sis), or hardening of the arteries.

When atherosclerosis affects the coronary arteries (the blood vessels that supply the muscles of the heart), the condition is called coronary artery disease, which puts a person at risk for having a heart attack. When atherosclerosis affects the blood vessels that supply the brain, the condition is called cerebral vascular disease, which puts a person at risk of having a stroke.

Atherosclerosis may also block blood flow to other vital organs, including the kidneys and intestines. This is why it's so important to start paying attention to cholesterol levels as a teen — you can delay or prevent serious health problems in the future.

What Causes High LDL Cholesterol Levels?

Some of the factors that can lead to high cholesterol are:

On the other hand, physical activity tends to increase HDL cholesterol levels, which reduces your chance of developing heart disease.

How Can I Lower My Cholesterol?

Some people who have high cholesterol levels need to be on medication as part of their treatment to lower it. Although most teens won't need to take medication to lower their cholesterol, it's still important to keep cholesterol in check because plaque can start to form during the teen years. To see if you have high cholesterol, talk to your doctor, who can test your cholesterol levels by taking a blood sample.

You can't change your genes, but you can do some things now to decrease your risk for heart disease later.

The 2010 Dietary Guidelines recommend that cholesterol intake should be less than 300 milligrams a day, total fat intake should be 25-35% your total calories, saturated fat should be 10% or less of the total daily calories, and trans fats should be kept as low as possible.

Also, maintain a healthy weight and get moving. Regular aerobic exercise — stuff like biking, walking, and swimming — strengthens your heart, lowers cholesterol, and helps you to lose excess weight. For people who smoke, quitting can help decrease the risk of heart disease.

Healthy Tips

Here are some helpful tips you can try:

If you are concerned about cholesterol and heart disease, talk to your doctor. Although not all the factors contributing to heart disease and high cholesterol can be controlled, many can. Start taking care of your body now and it will thank you in the future.

Reviewed by: Mary L. Gavin, MD
Date reviewed: July 2013





Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.

© 1995-2014 The Nemours Foundation/KidsHealth. All rights reserved.





Bookmark and Share

Related Resources
OrganizationAmerican Heart Association This group is dedicated to providing education and information on fighting heart disease and stroke. Contact the American Heart Association at: American Heart Association
7272 Greenville Ave.
Dallas, TX 75231
(800) AHA-USA1
Web SiteNational Center for Nutrition and Dietetics Offering nutrition information, resources, and access to registered dietitians.
Web SiteChooseMyPlate.gov ChooseMyPlate.gov provides practical information on how to follow the U.S. government's Dietary Guidelines for Americans. It includes resources and tools to help families lead healthier lives.
OrganizationAmerican Council on Exercise (ACE) ACE promotes active, healthy lifestyles by setting certification and education standards for fitness instructors and through ongoing public education about the importance of exercise.
Related Articles
About Vegetarian Recipes These recipes are for anyone following a vegetarian (meat-free) diet.
Figuring Out Fat and Calories From all you hear, you'd think fat and calories are really bad for you, but we all need a certain amount of them in our diets. Find out the truth about fat and calories.
Vegan Food Guide A vegan doesn't consume any animal-derived foods or use animal products or byproducts, and eats only plant-based foods.
Go, Slow, and Whoa! A Quick Guide to Healthy Eating Looking for an easy way to eat healthier? This article provides tips on choosing the right foods - and an easy-to-follow chart to guide you.
Easy Exercises for Teens Finding it hard to fit in fitness? Try these easy exercises for teens.
How Can I Lose Weight Safely? Lots of people are unhappy with their present weight, but aren't sure how to change it - or even if they need to. Get the facts on weight loss here.
Nutrition & Fitness Center Visit our nutrition and fitness center for teens to get information and advice on food, exercise, and sports.
Therapy and Weight Management Losing weight can feel like a challenge, no matter how much we want it. It can sometimes seem like our minds are working against us. That's where weight-management counselors can help.
Food Labels Look at any packaged food and you'll see the food label. This nutrition facts label gives the lowdown on everything from calories to cholesterol. Read more about food labels.
How Can a Vegetarian Get Protein? Find out what the experts have to say.
iGrow iGrow
Sign up for our parent enewsletter