The Facts About Healthy and Unhealthy Dietary Fats

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There are three types of dietary fats: saturated fat, unsaturated fat (of which there are two kinds: monounsaturated fat, polyunsaturated fat), and trans-fats. Unsaturated fats are ‘healthy fats,’ whereas unsaturated fats and trans-fats can raise cholesterol. While it’s not necessary to eliminate fat from your diet – indeed, some fat is absolutely necessary for good health– understanding which type of fats are found in foods we frequently eat will help balance fat intake and support a low-cholesterol diet.

Why Are Saturated And Trans Fats Bad For You?

Simply stated, saturated and trans-fats raise cholesterol whereas unsaturated fats do not. If you have high cholesterol – or are trying to avoid high cholesterol – choose foods high in unsaturated fats rather than cholesterol-boosting saturated and trans-fatty foods.

Which Foods Are High In Saturated Fat?

Saturated fats that can raise cholesterol are primarily found in both animal proteins like beef, veal, lamp and pork, as well as full-fat dairy products like butter, cream and cheese and other dairy products made from whole and 2% milk. Also, the ‘tropical oils’ (coconut and palm kernel oil) are also high in saturated fat. It’s important to limit consumption of these foods so they do not increase cholesterol.

A simple method that will help limit your saturated fat intake is to think about the type of meat and dairy you eat. Choosing poultry and/or lean cuts of meat in place of red meat is important. And for dairy and cheese, choose products made from skim milk rather than from full-fat or 2% milk.

Which Foods Are High In Trans-Fats?

Broadly, hydrogenated foods and ‘processed’ foods are high in trans-fat and should be avoided. For example, fast food (especially french fries), baked goods (doughnuts, cookies, crackers, muffins, pies, and cakes) and white bread are common foods high in trans-fats. Avoiding fast food and checking labels at the grocery store are key methods for avoiding foods high in trans-fats. The AHA recommends, “look for processed foods made with unhydrogenated oil rather than partially hydrogenated or hydrogenated vegetable oils or saturated fat.”

To avoid trans-fat foods, try to make most of your food selections from the perimeter of the grocery store – fresh fruits and vegetables along with low-fat meat and dairy – rather than the processed foods that live in the center aisles.

What Are The Good Dietary Fats?

Unsaturated fat, the ‘healthy’ dietary fat, is found in fish, nuts, seeds, avocados, and cooking oils that are plant-based. Oils containing unsaturated fat are generally liquid at room temperature – with one key exception: tropical oils like coconut or palm kernel oil are saturated fats.

According to the American Heart Association, “Some examples of foods that contain these fats include salmon, trout, herring, avocados, olives, walnuts and liquid vegetable oils such as soybean, corn, safflower, canola, olive and sunflower.” Replacing foods high in trans-fats and saturated fats with foods from this list of foods high in unsaturated fat is an important part of a low-cholesterol diet.

How Much Of Each Fat Should I Eat Daily?

The AHA publishes guidelines for the percent of fat from each of these fats that should be eaten daily, but it can be hard to think in percentages translate that into everyday living.  Instead, if you spend just a day or two counting calories and toting up nutritional values of the foods you often eat, you can get a handle on how much fat – of the different types of fat – you are eating.

Assuming a ‘standard’ 2,000 calorie per day diet, the AHA recommends that women, “consume less than 15 g saturated fat, less than 2 g trans fat and between 56 and 77 grams of total fat each day (with most fats coming from sources of polyunsaturated and monounsaturated fats, such as fish, nuts, seeds and vegetable oils).


Choosing largely unsaturated fats is an important part of a low-cholesterol diet. Try counting calories and grams of fat for a few days to see how your current diet stacks up – there are several food diaries out there and it’s not hard to do. If you’d prefer not to track calories and fat grams even for a few days, here’s a broad guideline from the AHA, “Keep total fat intake between 25 and 35 percent of calories, with most fats coming from sources of polyunsaturated and monounsaturated fatty acids such as fish, nuts and vegetable oils.”

Did You Know?

If you must use butter or margarine as a spread (for cooking you should replace with olive/vegetable oil), margarine is generally considered a better choice than butter because butter is made from animal fat so it contains saturated fats and cholesterol. However, some margarines are high in trans-fats, and should be avoided. Broadly, the more solid the margarine, the more trans-fat it contains. It’s best to choose soft or liquid margarines rather than stick margarine – and to check the label for trans-fat levels.


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