Effects of n-3 fatty acids on blood rheology.

In spite of the recent flurry of interest in n-3 fatty acids, haemorheological effects have been somewhat neglected. When quantifying blood rheology by means of blood viscosity, plasma viscosity, haematocrit, red cell deformability and red cell aggregation measurements, it is observed that all these parameters (except for haematocrit) are altered significantly when an increasing dose of n-3 fatty acids is given to volunteers. In patients with hyperlipoproteinaemias similar effects are seen during an 8-week medication period. n-3 fatty acids seem to increase blood fluidity by at least two independent mechanisms: changing red cell deformability possibly by altering the cell membrane composition, and lowering plasma viscosity possibly by altering the protein pattern of the plasma. The therapeutic potential of the observed changes lies in increasing blood flow in ischaemic tissues and needs to be explored more thoroughly.