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Home Fatty Acids Omega-3 fatty acids and major depression: A primer for the mental health professional
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Omega-3 fatty acids and major depression: A primer for the mental health professional |
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Page 2 of 7
Table 1
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Various Sources of EPA and DHA
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Fish/Seafood
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Total EPA/DHA (mg/100 g)
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Mackerel
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2300
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Chinook salmon
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1900
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Herring
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1700
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Anchovy
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1400
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Sardine
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1400
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Coho salmon
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1200
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Trout
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600
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Spiny lobster
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500
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Halibut
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400
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Shrimp
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300
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Catfish
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300
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Sole
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200
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Cod
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200
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USDA Nutrient Database http://www.nal.usda.gov
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The dietary intake of omega-3 fatty acids has dramatically declined in
Western countries over the last century, the North American diet
currently has omega-6 fats outnumbering omega-3 by a ratio of up to
20:1. There are a number of reasons for this skewed ratio, most notably
the mass introduction of the aforementioned omega-6 rich oils into the
food supply, either directly or through animal rearing practices [8].
The ideal dietary ratio of omega-6 to omega-3 has been recommended by
an international panel of lipid experts to be approximately 2:1 [9].
Given that approximately 20% of the dry weight of the brain is made up
of PUFA and that one out of every three fatty acids in the central
nervous system (CNS) are PUFA, the importance of these fats cannot be
argued [7]. Considering that highly-consumed vegetable oils have significant omega-6 to omega-3 ratios (see Table 2),
it is quite plausible that, for some individuals, inadequate intake of
omega-3 fatty acids may have neuropsychiatric consequences. While far
from robust at this time, emerging research suggests that omega-3 fatty
acids may be of therapeutic value in the treatment of depression.
Table 2
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Omega-6 and Omega-3 Content (%) of Dietary Oils
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Oil
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Omega-6
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Omega-3
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Safflower
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75
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0
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Sunflower
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65
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0
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Corn
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54
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0
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Cottonseed
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50
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0
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Sesame
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42
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0
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Peanut
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32
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0
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Soybean
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51
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7
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Canola
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20
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9
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Walnut
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52
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10
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Flax
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14
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57
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USDA Nutrient Database http://www.nal.usda.gov/
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Last Updated ( Sunday, 14 October 2007 )
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