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It's too simple to say that all fat is bad. We all need to eat some food that contains fats. Fats in the body are called lipids. They give us energy and help to transport vitamins around the body, for example.

But some fats are harmful. Eating these fats increases the level of bad cholesterol in your blood. See More about cholesterol and triglycerides.

Here's a guide to different types of fats, what foods you can find them in, and what effect they have on cholesterol and triglycerides in your blood.

This information is for educational use only, and is not a substitute for prompt professional medical advice. Readers should always consult a physician or other professional for advice and treatment. ©BMJ Publishing Group Limited 2008. All rights reserved.