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The low-down on fat

Healthy adults should limit their total fat intake to no more than 30 percent of calories. This does not mean that each food, recipe or meal must measure up properly, but rather that you consider the total calories eaten over several days, such as a week.

The basic three

There are three major types of fat—and not all are created equal:

  • Monounsaturated fats are your best choice. These fats may help reduce blood cholesterol. Sources include olive oil, canola oil, peanut oil, nuts and avocados.
  • Polyunsaturated fats may also help lower blood cholesterol. Sources include vegetable oils such as safflower, corn, soybean, sesame and sunflower oil. Omega-3 fats, a certain type of polyunsaturated fat, are also heart friendly. Sources include fatty fish, such as mackerel, tuna, salmon, sardines, haddock and herring.
  • Saturated fats can raise the blood cholesterol level and should, therefore, be limited to 7 percent of your dietary calories. Sources include meat, poultry with skin, butter and whole-milk dairy products, coconut oil, palm oil and cocoa butter.

Caution, please!

An excess amount of the following substances can increase the risk of heart disease:

  • Hydrogenated and trans fats occur in nature in some meat and dairy products and are also formed during the hydrogenation of oils. Hydrogenation is used in food processing to extend the shelf life of certain foods. Many commercial products, such as stick margarines and cookies, are known to contain trans fats. Avoid trans fats by limiting your consumption of saturated animal fats and choosing natural, unhydrogenated oil. Buy processed foods made with unhydrogenated oil. In choosing margarines, pick soft varieties over stick varieties and look for labels that list liquid vegetable oil as the first ingredient with no more than two grams of saturated fat per tablespoon.
  • Cholesterol is a soft, waxy substance that your body needs and produces in sufficient amounts, so you should limit the amount you eat to less than 300 milligrams a day. Cholesterol is only found in animal products. Cholesterol is carried in the blood by lipoproteins, including low-density lipoprotein. When a person has too much LDL (“bad” cholesterol) in the bloodstream, it can build up to dangerous levels within the artery walls. Some cholesterol is carried by high-density lipoprotein (HDL), which tends to sweep cholesterol away from the arteries and back to the liver, where it is eliminated. HDL is known as “good” cholesterol because a high level seems to protect against heart attack. Conversely, low levels of HDL can indicate a higher risk of heart disease.
  • Triglycerides are the chemical form in which most fat exists in food and in the body. Calories not used immediately are converted to triglycerides and stored. To reduce triglycerides, reach and maintain a good body weight; reduce saturated fat, cholesterol and alcohol; and stick to a regular exercise program.