THE DANGEROUS SIDE OF FISH OIL
Report #7246
Many North Americans take fish oil pills because they think it helps to protect them from suffering heart attacks.
A recent study from China shows that fish oil pills may increase some people's chances of getting a heart attack. Before the bad LDL cholesterol can form plaques that plug arteries, it must be converted to another form called oxidized LDL cholesterol. Taking extra fish oils causes the body to form a type of LDL cholesterol that is unusually susceptible to forming oxidized LDL plaques.
Many studies show that people who eat deep sea fish twice a week are less likely to suffer heart attacks than people who don't eat fish. Deep sea fish oils contain omega-3 polyunsaturated oils that help to prevent the clotting that causes heart attacks. However, this benefit maximizes at eating fish twice a week. There is no additional benefit from eating fish more often than twice a week. So eating moderate amounts of deep sea fish may help prevent heart attacks, but taking extra fish oils may actually cause heart attacks by causing more plaques to form.
By Gabe Mirkin, M.D., for CBS Radio News
Tsai, P.J.; Lu, S.C. Fish oil lowers plasma lipid concentrations and increases the
susceptibility of low density lipoprotein to oxidative modification in healthy men.
Journal of the Formosan Medical Association. SEP 1997;96(9):718-726. The fish oil diet
significantly reduced the plasma concentrations of total cholesterol, total triglyceride,
very low density lipoprotein (VLDL)-cholesterol, and VLDL-triglyceride (p <0.05) compared with the soybean oil diet, irrespective of dietary cholesterol content. Our results suggest that fish oil lowers plasma lipid levels significantly but results in a form of LDL that is more susceptible to oxidation in vitro."
Reported 10/6/97; Checked 9/5/05