Essentials of Nutrition for Sports

Sources Nutrient Alpha-Linolenic Acid

Alpha-linolenic acid is found in plants, particularly flax seed and

oil, canola and soybean oils, and English walnuts. It is also abundant in perilla seeds and oils and in

purslane, a vegetable used in the

Middle East.

The average daily adult intake of alpha-linolenic acid is about

1.4 grams for men and about 1.0 grams for women, just below the FNB recommended AIs.

Alpha-linolenic acid content of selected foods is listed in

Table

13

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Food

Serving

Alpha-Linolenic acid, g

Flaxseed oil

1 tablespoon

8.5

Walnuts, English

1 ounce

2.6

Flaxseeds

1 tablespoon

2.2

Walnut oil

1 tablespoon

1.4

Canola oil

1 tablespoon

1.2

Mustard oil

1 tablespoon

0.8

Soybean oil

1 tablespoon

0.9

Walnuts, Black

1 ounce

0.6

Olive oil

1 tablespoon

0.1

Broccoli, raw

1 cup, chopped

0.1

Table 13. Alpha-linolenic acid content of selected foods. Eicosapentaenoic Acid, Docosahexaenoic Acid

Fish oils and fatty fish are major dietary sources of

eicosapentaenoic acid and docosahexaenoic acid.

Fatty fish include salmon, rainbow trout, sardines, and mackerel. The average daily adult intake of eicosapentaenoic acid is about

0.05 grams per day. The average daily adult intake of docosahexaenoic acid is about 0.07 grams per day.

Omega-3 fatty acid-enriched eggs are available. One such egg produced by adding flaxseed to hens’ feed is

reported to contain 0.25 g of eicosapentaenoic acid and 0.15 g of docosahexaenoic acid.

Eicosapentaenoic acid and docosahexaenoic acid content of

selected foods is listed in

Table 14

.

Food

Serving

EPA, g

DHA, g

Cod, Pacific, cooked

3 ounces

0.09

0.15

Crab, Dungeness, cooked

3 ounces

0.24

0.10

Herring, Pacific, cooked

3 ounces

1.06

0.75

Oysters, Pacific, cooked

3 ounces

0.75

0.43

Salmon, Atlantic, cooked

3 ounces

0.28

0.95

Salmon, Chinook, cooked

3 ounces

0.86

0.62

Salmon, sockeye, cooked

3 ounces

0.45

0.60

Sardines, packed in oil

3 ounces

0.77

0.65

Shrimp, cooked

3 ounces

0.15

0.12

Trout, rainbow, cooked

3 ounces

0.40

0.44

Tuna, white, packed in water

3 ounces

0.20

0.54

Fish oil, menhaden

1 gram

0.13

0.09

Fish oil, salmon

1 gram

0.13

0.18

Table 14. Eicosapentaenoic acid a

nd docosahexaenoic acid content of

selected foods. Synthesis of Eicosapentaenoic and Docosahexaenoic Acids

Humans can synthesize eicosapentaenoic acid and

docosahexaenoic acid from alpha-linolenic acid.

In men, about 8% of dietary alpha-linolenic acid is converted to

eicosapentaenoic acid and up to 4% is converted to docosahexaenoic acid.

In women, about 21% of dietary alpha-linolenic acid is converted

to eicosapentaenoic acid and 9% is converted to docosahexaenoic acid.

Variations in dietary omega-6 and long-chain omega-3

eicosapentaenoic acid levels may affect the efficiency of alpha-

Nutrition for Sports, Essentials of 82