A study has shown that fish oils are more effective than the statin drug Lipitor in positively affecting the levels of HDL ("good") cholesterol in obese and insulin-resistant men. HDL cholesterol protects against atherosclerosis by removing excess cholesterol from arterial cells, and low HDL levels can increase the risk of cardiovascular disease, particularly for those who are obese or insulin resistant.
In the six-week study, fish oils and Lipitor were given to 48 men, both separately and combined. Fish oil and Lipitor together greatly lowered plasma triacylglycerols and raised HDL cholesterol levels.
But only fish oil also influenced HDL cholesterol by altering the production and catabolism rates of HDL apolipoproteins (catabolism is the breakdown of complex molecules metabolically into simpler ones). Lipitor did not increase this effect when combined with the fish oils, and did not produce a similar effect on its own.