Comparison of vegetable and fish oil in the provision of N-3 polyunsaturated fatty acids for nervous tissue and selected organs

Rats were fed (ns were their mothers from 2 weeks before mating) with a semi-synthetic diet deficient in alpha-linolenic acid (peanut oil-based) but containing linoleic acid At age 5 weeks, the animals were divided into several groups that were fed for 3 weeks varying amounts of (n-3) series polyunsaturated fatty acids, either as alpha-linolenic acid (by addition of rapeseed oil to the peanut oil) or as very long chain acids (by addition of fish oil). Compared with vegetable oil, equal quantities of fish oil gave a higher concentration of docosahexaenoic acid (DHA) in all the tissues. About two-fold more vegetable oil than fish oil was needed to obtain the same quantity of DHA in all the tissues. Three weeks of the new diet were not enough to stabilize DHA concentrations in rat nervous tissue, but recovery was more rapid with fish oil than with vegetable oil. For non-nervous tissue, increases in DHA levels were lower with vegetable oil than with the same amount of fish oil, and fish oil provided more very long chain (n-3). (C) Elsevier Science Inc. 1997.