Although saturated fat and cholesterol in the diet are pathogenic for cardiovascular disease, the n-3 fatty acids from fish are actually protective and by a variety of mechanisms prevent coronary deaths and, in particular, cardiac arrest.

Ideally, the diet best designed to produce the optimal action to prevent cardiovascular disease would be low in saturated fatty acids and high in EPA and DHA from fish or fish oil (13). The low-saturated fat diet would lower total cholesterol and LDL and the fish oil would lower tniacylglycerol and VLDL. However, as already emphasized, the most powerful action of the n-3 fatty acids from fish and fish oil in cardiovascular disease is to prevent ventricular fibrillation and sudden death.

PMID: 9209190

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