Omega-3 fatty acids: where to find them?

Last Updated : 03 July 2003

Although no single food alone can make a person healthy, eating more fish is one way that most of us can help improve our diets—and our health. Many of the studies about beneficial omega-3 fatty acids focus on fish as the primary source. Salmon, sardines, tuna and even shellfish are rich in omega-3 fatty acid content, but increasing your consumption of all types of fish and seafood is recommended.

Sorting out your fats

Experts agree that a diet based on moderation and variety is essential to good health. In other words, eating some of a wide variety of foods provides more complete nutrition and is more beneficial overall than a diet that relies on just a few foods.

It is generally recommended to choose a diet that is low in saturated fat and cholesterol and moderate in total fat. Fatty meats and full-fat dairy products are the major sources of saturated fat in the diet. Sources of unsaturated fats are primarily vegetable oils. Diets higher in monounsaturated and polyunsaturated fats lower "bad" cholesterol levels, while saturated fats increase "bad" cholesterol. Therefore, an ideal diet would be higher in monounsaturated and polyunsaturated fats than the current European diet.

Increase Your Omega-3s

Within the polyunsaturated fat category, there are two important subclasses of fatty acids: omega-3s and omega-6s. Vegetable oils are rich in omega-6 fatty acids, and most Europeans unknowingly get plenty of them in the diet. On the other hand, omega-3 fatty acids are generally lacking in our diets. They are found in fish, shellfish, tofu, almonds, walnuts as well as in some vegetable oils such as linseed, nuts and canola (rapeseed). Omega-3s have a positive effect on cardiovascular health. Another intriguing area of research on omega-3 fatty acids pertains to their role in brain and visual function, as some research suggests they may have a role in preventing macular degeneration, a common form of blindness, and have beneficial effects in some depressive disorders.

Continuing research involves the role of omega-3 fatty acids and the immune system, and suggests a positive influence on rheumatoid arthritis, asthma, lupus, kidney disease and cancer.

It is recommended that you eat fish rich in omega-3 fatty acids twice a week in order to reap specific health benefits. Although all fish aren't high in omega-3s, they still can contribute important amounts of these fatty acids if they're eaten regularly. The following chart provides a general overview of fish and their omega-3 fat content.

Omega-3 Content of Fish and Shellfish (Amounts are in grams per 100g portion*)
Salmon, Atlantic, farmed, cooked, dry heat	1.8
Anchovy, European, canned in oil, drained	1.7
Sardine, Pacific, canned in tomato sauce, drained solid with bone	1.4
Herring, Atlantic, pickled	1.2
Mackerel, Atlantic, cooked, dry heat	1.0
Trout, rainbow, farmed, cooked, dry heat	1.0
Swordfish, cooked, dry heat	0.7
Tuna, white, canned in water, drained solids	0.7
Pollock, Atlantic, cooked, dry heat	0.5
Flatfish (flounder and sole species), cooked, dry heat	0.4
Halibut, Atlantic and Pacific, cooked, dry heat	0.4
Haddock, cooked, dry heat	0.2
Cod, Atlantic, cooked, dry heat	0.1
Mussel, blue, cooked, moist heat	0.7
Oyster, Eastern, wild, cooked, dry heat	0.5
Scallop, mixed species, cooked, dry heat	0.3
Clam, mixed species, cooked, moist heat	0.2
Shrimp, mixed species, cooked, moist heat	0.3
Source: USDA Nutrient Database for Standard Reference

Nutritionally, how does fish compare with meat?

Fish and shellfish are excellent sources of protein that are low in fat. A 100 gram serving of most fish and shellfish provides about 20 grams of protein, or about a third of the average daily recommended protein intake. The protein in fish is of high quality, containing an abundance of essential amino acids, and is very digestible for people of all ages. Seafood is also generally lower in fat and calories than beef, poultry or pork and contain about the same or slightly less cholesterol. The fat content of fish varies depending on the type of fish and season. Shellfish and white fish have very low fat containing less than 5% fat (e.g: shrimps, lobster, mussels, squid, haddock, cod, plaice, sole). Oil-rich fish fat content ranges from 5-25%; sardine and tuna (5-10%), kippers, anchovies, mackerel, salmon (10-20%) and eel (25%). Although oily fish contains quite some fat, the fat is mainly unsaturated. Seafood is also loaded with minerals such as iron, zinc and calcium (canned fish with soft, edible bones).

Getting Into The Swim Of It

Adding more fish and seafood to your diet is easy. One helpful tip is simply substitution. Slowly try substituting fish for one or more types of protein, thus establishing a twice-weekly seafood routine.

Updated Information

EUFIC Review (2014). Facts on Fats - the Basics
EUFIC Review (2015). Facts on Fats - Dietary Fats and Health
Q&A (2015). 8 Facts on Fats