Good Fats and Bad Fats

The Skinny on Fats

Fats and oils are part of a healthy diet and play many important roles in the body. Fat provides energy and is a carrier of important nutrients such as vitamins A, D, E, and K and carotenoids derived from vitamin A. But fat can impact the health of our hearts and arteries in a positive or negative way, depending on the types of fat we eat. Doctors and nutritionists recommend getting between 20 and 35 percent of calories from total fat, with most fats coming from sources of “good” fat, such as fish, nuts, and vegetable oils.

The right fats are actually good for you

After so many years of being told otherwise, the idea that fat is good for you is hard to swallow, but true. Are you eating the right type of fat? There are good fats and bad fats to look for in your diet.

Fat Facts: What’s Good About Fat

Fat is the target of much scorn, yet it serves up health benefits you can’t live without. For example:

  • Fat supplies essential fatty acids (EFAs) – Our bodies are incapable of producing the EFAs, known as linoleic acid (LA) and alpha-linolenic acid (ALA), so it must derive them from the food we eat
  • Fat ferries certain nutrients into and around the body – vitamins A, D, E, and K (known as the fat-soluble vitamins) are the best known. They are also stored in fat.
  • Fat is necessary for certain functions in the body – Fat helps maintain healthy skin. It is also important for promoting proper eyesight and is important for brain development in babies and children

Fat Facts: What’s Bad About Fat

I can’t say it enough but there is a well-established link between fat intake and heart disease and stroke risk. Diets that are rich in saturated fat and trans fat (both “bad” fats) raise blood cholesterol concentrations. This contributes to clogged arteries that block the flow of oxygen-rich blood to the heart and brain. But, and this is a big but, very low-fat diets (15% or 34 grams of fat in a 2,000-calorie diet) may not reduce artery-clogging compounds in the bloodstream in everyone. And most people cannot maintain a very low-fat diet in the long run because it doesn’t taste good.. The American Heart Association (AHA) recommends that we get 20% to 35% of our calories from fat. Most Americans get 34% or more.
So remember this -When it comes to dietary fat, quantity and quality count. Dietary fat is categorized either as saturated or unsaturated. Unsaturated fats, both monounsaturated and polyunsaturated, should always be the predominant type of fat in a balanced diet, because they reduce the risk of clogged arteries.
Foods tend to contain a mixture of fats. Monounsaturated fat is the primary fat found in olive, canola, and sesame and avocado oils. It is also found in nuts such as almonds, cashews, and pistachios, peanuts and peanut butter. Polyunsaturated fat is prevalent in corn, cottonseed, safflower oils, as well as in flaxseed and flaxseed oil. Other sources of polyunsaturated fats include sunflower seeds and sunflower oil, soybeans and soybean oil, tub margarine and seafood.

The Facts on Omega-3 Fats

When it comes to good-for-you fat, seafood stands out. Seafood harbors omega-3 fats called DHA (docosahexanoic acid) and EPA (eicosapentanoic acid), unsaturated fats considered central to a child’s brain development and eyesight, and for heart health. The table below compares the Omega-3 unsaturated fats in a variety of fish.

Type of FishOmega-6Omega-3ALA
Halibut (Pacific)
Herring (Atlantic)
Herring (Pacific)
Salmon (farmed Atlantic)**
Salmon (Chinook)
Salmon (Coho)
Salmon (Sockeye)
Sole (Lemon)0.70.2?
Trout (Lake –pink meat)?2.0?
Trout (Rainbow)?0.5?
Tuna (canned Albacore)***
Tuna (canned Bluefin)***

*Another source lists this as less than 0.3
**Farm-raised fish are fed some combination of vegetable and fish oils. A Norwegian study (2004) found that Omega-3 was very low in salmon on pure vegetable oil. Dioxins and PCBs tend to concentrate in oil, so feeding fish oil to fish can significantly raise levels above those in wild populations. Lowest are wild Alaskan and British Columbia salmon.
***One source gives much lower values when tuna is packed in water.
Limit saturated and trans fats, and cholesterol. Eating too many saturated and trans fats, or cholesterol, may raise the level of LDL (bad) cholesterol and increase your risk of heart disease. A saturated fat, the type of fat that is solid at room temperature, is found mostly in animal-based food products. A trans fat is made when liquid vegetable oil is processed to become solid. And cholesterol is a fatty substance found only in animal-based products like egg yolks and whole milk. It is important to eat less than 10 percent of your calories from saturated fats. How do we figure this out?

For example, if you aim to eat 1,250 calories per day, your daily allowance of saturated fat would be less than 10 percent of 1,250 calories or 125 calories. There are approximately 9 calories in a gram of fat. OK, OK. To make the math easier, we’ll use 10 calories per gram of fat. This at least gives you the right idea. Therefore, 125 calories/ 10 g/cal. = 12.5 g which is less than the 100% DV for saturated fat. The table to the right shows the saturated fat limits for people with various calorie needs. Also, you should keep trans fats as low as possible, and eat less than 300 milligrams of cholesterol each day. These limits are recommended so you will not consume too much saturated fat and too many calories in your healthy eating plan.
Unhealthy fats such as saturated and trans fats, and cholesterol, are found in many foods. So, look for choices that are lean, fat-free, or low-free when selecting and preparing meat, poultry, dry beans, and milk products. But be careful, because food manufacturers will add hidden sugars to “fat-free” or “low-fat” products to make them taste better when the fat is removed or reduced. Remember also to look at the fat in the food label and what is the serving size! Serving size may not equate to “eating size.” An easy and quick way to reduce saturated fats is to trim excess fat from meat and poultry and remove the skin from poultry. Additionally, watch out for foods processed or made with certain oils (for example, palm oil, palm fruit oil, palm kernel oil, and coconut oil) that increase the amount of saturated fats in the food. Examples of foods that tend to have saturated fats are fatty cuts of meat, whole milk products, cakes, cookies, pies, crackers, candy, candy bars, household shortening, and creamers. Limiting these foods can reduce saturated fats in your diet.
Trans fats are mostly found in food products made with shortening and partially hydrogenated vegetable oils (liquid oil that is processed to become a solid fat). Most of the trans fats Americans eat come from cakes, cookies, crackers, pies, fried potatoes, household shortening, and hard (stick) margarine. Look for partially hydrogenated oil in the food label and limit these foods. Limiting consumption of many processed foods is a good way to reduce trans and saturated fats.

OilTotal FatSaturated FatsPolyunsaturated FatsMonounsaturated FatsComments
Canola Oil14g1g4g8g1 Omega-3 and 3 Omega-6
Coconut Oil14g12g0.2g0.8g0 Omega-3 and 0 Omega-6; high in medium-chain triglycerides
Corn Oil14g2g8g4g0 Omega-3 and 8 Omega-6
Flaxseed Oil14g1g10g3g7 Omega-3, 2 Omega-6 and 2 Omega-9 (monounsaturated)
Grapeseed Oil14g1.3g10g2.2gVery low in Omega-3 and very high in Omega-6
Olive Oil14g2g1g10g0 Omega-3 and 1 Omega-6; high in monounsaturated and high in antioxidants if unprocessed
Peanut Oil14g3g5g6g0 Omega-3 and 4 Omega-6
Safflower Oil14g2g10g2g0 Omega-3 and 8 Omega-6
Sesame Oil14g2g6g5g0 Omega-3 and 6 Omega-6
Soy Oil14g2g6g1.5g1 Omega-3 and 7 Omega-6
Sunflower Seed Oil14g2g9g3g0 Omega-3 and 8 Omega-6
Wheat Germ Oil14g1g9g3g1 Omega-3 and 7 Omega-6
 # of kernels/oz21236-81810-12 20 halves1674914 halves
Total Fatg17.2214.0118.8313.1421.5713.9620.419.3813.0318.49
Saturated Fatg1.2661.0584.2912.5963.3871.9371.7521.3891.5751.737
Monounsaturated Fatg12.9428.7576.9597.74416.8046.92611.5675.3206.8652.533
Polyunsaturated Fatg2.2453.4635.8242.222.4254.4116.1289.6593.94013.374
Pantothenic acidmg.
Vitamin B6mg.
Vitamin Kmcg4.0009.8n/a0115.33.7.8
Vitamin Emg4.267.431.
Total Phytosterolsmg2731n/a45326229406120

Source: USDA National Nutrient Database for Standard Reference, Release 20, 2007.
*g = gram; **mg = milligram; ***%DV = percent Daily Value; ****mcg = microgram
¹All of the nuts are unsalted; almonds, brazil nuts, hazelnuts, pecans, pine nuts and walnuts are unroasted; cashews, macadamias and pistachios are dry roasted.