Olive oil- and sunflower oil-fried sardines in the prevention of rat hypercholesterolemia.

The effect of diets containing olive-oil-fried sardines (diet 1) or sunflower-oil-fried sardines (diet 3) upon the serum cholesterol-raise induced by dietary cholesterol was studied after a 4-week experiment in growing Wistar rats. Results of diet 1 were compared to those obtained in diets containing casein plus olive oil (diet 2), whereas results of diet 3 were compared to those obtained with casein plus sunflower oil (diet 4). All diets contained cholesterol and bovine bile as a cholesterol-raising agent. The hypercholesterolemic effect of dietary cholesterol in fried-sardine groups (a total cholesterol (TC) increase of 0.9 mmol/L (p < 0.05 and 0.4 mmol/L (not significant) in groups 1 and 3, respectively) was markedly lower than in groups 2 and 4 (a TC increase of 13.9 mmol/L (p < 0.01) and 18.2 mmol/L (p < 0.01), respectively). Serum triglyceride levels decreased in fried-sardine diets (p < 0.05) while they increased in casein diets (p < 0.05). HDL-cholesterol levels appear lower in diet 1 than in diet 2 (p < 0.05), but similar in diets 3 and 4. However, HDL-fraction carries in diets 1, 2, 3 and 4, 13%, 4%, 53% and 5% of TC, respectively. Results showed that fried-sardine diets exert a powerful check effect on the cholesterol-raising effect induced by dietary cholesterol.