Journal Name:
Am J Clin Nutr
Article Title:
Influence of long-term diet modification on platelet function and composition in Moselle farmers
Date Written:
1986
Volume:
43
Number:
NA
Page:
136
Author(s):
Renaud, S.; Godsey, F.; Dumont, E.; Thevenon, C.; Ortchanian, F.; Martin, J.L.
Article:
In this landmark study conducted in 1986, dietary canola oil supplementation was used to determine if alpha-linolenic (ALA) intake can influence platelet function. Platelet function and composition, lipemia, and dietary habits were evaluated yearly in 98 male farmers from Moselle (East of France) before and after decreasing, in half of them, dietary saturated fats from 16.2% to 9.9% of calories (P/S from 0.32 to 0.97). Dietary modification over the period was through substitution of normal fats with oil and margarines, Subjects were provided margarines in which polyunsaturated fatty acids were either 53.7% (group P) made only from sunflower oil, or were 50.2% (group A) from sunflower and canola oil. The oil supplied to the 2 groups was a mixture of sunflower and canola oil such that both groups received ALA in addition to omega 6 linoleic acid. A remaining two groups (B and R), used as controls, were advised to keep their dietary habits for one more year.
One year after these dietary changes, cholesterol and triglycerides decreased by approximately 10%, platelet aggregation to thrombin decreased by 81%, and platelet clotting activity was reduced by 30%. However, ADP aggregation was enhanced by 54%. At 2 yr the P/S was decreased to 0.7 and diet was also modified in controls, with 18:2 being increased mostly in one group (P/S = 0.81) and 18:3 in another (P/S = 0.59). In both groups, the main platelet function tests were significantly depressed 1 yr later.
The present long-term diet modification in French farmers with P/S ratio from 0.6 to 1.0 suggests:
1) Thrombin-induced aggregation was the parameter the most efficiently influenced by a decrease in the intake of saturated fat and a concomitant increase in polyunsaturated fat.
2) ADP aggregation was not beneficially influenced by a P/S ratio of approximately 1.0 especially with a high intake of both 18:2 and 18:3.
3) The aggregation to collagen, without being influenced as markedly as thrombin, could be improved especially when the P/S ratio was depressed to 0.6-0.8.
The authors speculate that ALA is more closely associated than 18:2 with improved clotting activity of platelets and aggregation to thrombin. This is in accordance with beneficial effects of omega 3 fatty acids on platelet functions, especially eicosapentaenoic acid 20:5 (n-3) which was significantly increased in plasma and platelet lipids in response to a higher intake of ALA.
The present study was one of the first to demonstrate that simply changes to a person’s fat intake through the replacement of SFA with canola oil can influence beneficially all the platelet function tests found to be increased in populations with a high intake of saturated fats, associated with a high mortality rate from CHD. These moderate changes in dietary habits consist mostly of replacing dairy fats by canola oil and margarines.
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