Fish oil and safflower oil change plasma fatty acids in women
What it found
In ten young women, a five-day fish diet raised plasma EPA and DHA and lowered the n-6/n-3 ratio, while a safflower oil diet raised linoleic acid.
The study was in people.
What they found
Studies in people
Linoleic acid changes
The proportion of linoleic acid fell in the plasma of women on the fish diet and rose in those on the safflower oil diet.
EPA and DHA rise
Plasma levels of EPA and DHA were significantly higher in the fish diet group.
Fatty acid ratios
The ratio of EPA to arachidonic acid was higher, and the n-6/n-3 and n-9/n-3 ratios were lower, in the fish diet group compared with the safflower oil group.
No change in some fats
No significant difference was seen in the proportion of alpha-linolenic acid between the two groups.
What the authors conclude
“From these results, it seems likely that fish oil in the common Japanese diet is a favorable source of plasma EPA and DHA even in such short term supplementation and with such a small amount of daily consumption.”
Also in their conclusions
- They say it seems likely that fish oil in the common Japanese diet is a favorable source of plasma EPA and DHA even in such short term supplementation and with such a small amount of daily consumption.
- They conclude that the fish diet enriched blood plasma lipids in the n-3 family polyunsaturated fatty acids, especially EPA, and remarkably decreased the n-6/n-3 ratio even though these subjects ingested such a small amount of these acids in the common Japanese diet for an experimental period as short as 5 days.
How it was done
The authors wanted to see how fish oil and safflower oil, as the main polyunsaturated fats in a common Japanese diet, affect plasma fatty acids in humans.
Ten female student volunteers aged 21 to 22 were split into two groups of five. One group ate a fish diet and the other a safflower oil diet for five days. Blood was taken at the start, on day three, and on day five.
What it can’t tell you
- This was a small study of ten young women over five days, so the results may not apply to other people or longer periods.
- The study measured plasma fatty acid levels, not health outcomes like heart disease.
Who paid
- Authors work at
- University of Ilorin, Nigeria
The paper
- Title
- Effect of fish oil and safflower oil in common Japanese diet on human plasma fatty acid composition
- Type
- Study
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Ogunleiye AJ, Muraoka A, Niizeki S, et al (1990). Effect of fish oil and safflower oil in common Japanese diet on human plasma fatty acid composition. Journal of nutritional science and vitaminology. doi:10.3177/jnsv.36.4-supplementi_423Free full textPubMed 2150530DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error