Two factors may affect the cholesterol level in the blood: genetics and foods.

An inherited genetic condition (familial hypercholesterolemia) results in very high LDL cholesterol levels. It begins at birth, and may result in heart attack at an early age.

The following types of fats may raise the cholesterol level:

Saturated fats
Saturated fats raise total blood cholesterol level. They are found in meat, seafood, cheese, milk,  ice cream and egg yolks.

Trans fats
Trans fats are more harmful than saturated fats because they raise bad LDL and lower good HDL. They are produced by heating liquid vegetable oils in the presence of hydrogen (a process called hydrogenation). They are found in French fries, deep-fried chips and most margarines.