There are two types of cholesterol:

• blood cholesterol, and
• cholesterol found in food.

Most of the cholesterol found in our blood is produced by our bodies from some of the fats that we eat. Some cholesterol is needed for vital body functions, but some fats can cause the body to produce more blood cholesterol than is needed. By changing the types of higher fat foods eaten, we can control blood cholesterol levels to some extent. (Read on for types of fats in food.)

A very small amount of the cholesterol in our blood comes from the cholesterol found in foods. Dietary cholesterol is found only in animal food products such as meat, fish, poultry, eggs, and dairy products. Few people need to restrict cholesterol from food since the body produces excess blood cholesterol from the fats we eat.

Low density lipoproteins (LDL) are made of mostly cholesterol, which is carried throughout the body. High levels of LDL mean that there is excess cholesterol in the blood, which could be deposited on the inside artery walls. This is why LDL is commonly referred to as being "bad" cholesterol.

High density lipoproteins (HDL) contain small amounts of cholesterol and act like scavengers in the body, picking up excess cholesterol for elimination from the body. HDL is often called "good" cholesterol.

Saturated fat is solid to semi-solid at room temperature. It is found mainly in animal products such as meat, poultry, cream, butter, higher fat milk, and regular cheeses. There are also some vegetable sources including coconut oil, palm oil, and hydrogenated vegetable oils e.g., shortening.

Saturated fats tend to raise LDL or bad cholesterol.

Trans fatty acids are formed during a food production process called hydrogenation. This process involves taking a liquid fat and making it harder. For example, vegetable oil is used to make hard margarine and shortening. Other food sources include some cookies, crackers, and deep fried products.

Trans fats tend to raise LDL or bad cholesterol.

Polyunsaturated fats are liquid at room temperature. They are primarily found in corn, sunflower, safflower and soybean oil, and in fish.

Polyunsaturated fats tend to lower blood cholesterol.

Monounsaturated fats are liquid at room temperature and are primarily of plant origin. They are found mainly in olive and canola oil.

Monounsaturated fats tend to have either a neutral effect on blood cholesterol or may slightly decrease LDL cholesterol.

Choose a balanced diet by following Canada's Food Guide to Healthy Eating and eating a variety of foods from each food group.

Watch the total amount of fat eaten, especially saturated and trans fats. Choose deep fried foods less often and prepare foods with a minimum amount of fat. Substitute oils for other types of fat whenever possible.

Choose leaner, well trimmed cuts of meat and lower fat dairy products more often.

Choose whole grain breads, cereals, and other grain products and vegetables and fruits often. In addition to other nutrients, the fibre found in these foods is important for good health. Soluble fibre can help to reduce blood cholesterol levels. It is mostly found in fruit, vegetables, dried peas, beans and lentils, barley, and oats.
Achieve and maintain a healthy body weight by enjoying regular physical activity and healthy eating.

Please ask your doctor to refer you to a dietitian if you need to lower your blood cholesterol. This is especially important if you have other risk factors for heart disease such as high blood pressure or diabetes, and if you are a smoker or are overweight.

For more information, call your local public health nutritionist or dietitian.