Effects of dietary fish oil on platelet function and plasma lipids in hyperlipoproteinemic and normal subjects.
Level 2 - randomized trial
Individual randomized crossover trial
PubMed 3178928 · doi:10.1016/0021-9150(88)90158-x
What was done
A randomized crossover trial evaluated dietary supplementation with an encapsulated fish oil concentrate (Maxepa, providing 3.24 g EPA and 2.16 g DHA daily) compared to a safflower oil control for 6 weeks each. The study included 25 participants across three groups: 9 normal subjects, 10 patients with type IV hyperlipoproteinemia, and 6 patients with type IIB hyperlipoproteinemia. Outcomes measured were platelet function, thromboxane synthesis, total plasma fibrinolytic activity, and plasma lipids and lipoproteins.
What was found
Fish oil slightly prolonged bleeding time in all groups and modestly inhibited platelet aggregation in type IV hyperlipoproteinemic and normal subjects. In normal subjects, thromboxane synthesis showed a 41% partial inhibition from baseline. Plasma total fibrinolytic activity did not change significantly in any group. Fish oil markedly decreased triglycerides and VLDL-cholesterol. HDL-cholesterol increased after fish oil in type IV hyperlipoproteinemics (4.11 +/- 0.13 mmol/l vs. 3.10 +/- 0.16 mmol/l, Maxepa vs. safflower oil), while an adverse increase in LDL-cholesterol was also noted in this group.
Why it matters
The study shows that high-dose fish oil reduces triglycerides with minor antiplatelet effects, but may lead to an unfavorable rise in LDL-cholesterol in type IV hyperlipoproteinemia.
Limits
The sample size was very small (n = 25 total across three subgroups), the intervention duration was short (6 weeks), clinical cardiovascular outcomes were not evaluated, and key numerical data for several outcomes were not reported in the abstract.
Cited by
- context In early research by Dr. Bill Harris, administering 30 grams of omega-3 per day to humans produced no negative effects over a short duration.