LDL cholesterol is considered the 'bad cholesterol' because it can contribute to plaque build-up in the artery walls - which can narrow the arteries, and set the stage for heart attacks and strokes..A study published in the Journal of the American College of Cardiology found that six widely used dietary supplements promoted for improving heart health including brands of fish oil, cinnamon, garlic and turmeric were not effective at lowering bad cholesterol.The study compared the impact of these particular supplements to the impact of a low dose of a statin (cholesterol-lowering medication) or a placebo. The study involved 190 adults with no prior history of cardiovascular disease. Study participants were ages 40 to 75, and different groups got a low-dose statin called rosuvastatin, a placebo, fish oil, cinnamon, garlic, turmeric, plant sterols or red yeast rice for 28 days. The statin had the greatest impact and significantly lowered LDL compared with the supplements and placebo.The average LDL reduction after 28 days on a statin was nearly 40 per cent. The statin also had the added benefit on total cholesterol, which dropped on average by 24 per cent and on blood triglycerides, which dropped 19 per cent. None of the people who took the supplements saw any significant decrease in LDL cholesterol, total cholesterol or blood triglycerides, and their results were similar to those of people who took a placebo.