High cholesterol levels and the use of cholesterol-lowering drugs called statins were both linked to a lower risk of colorectal cancer, but new research shows that a high cholesterol level is what's responsible for lowering cancer risk.

According to the new study published in the journal PLOS Medicine, blood cholesterol levels are inversely related with the risk of colorectal cancer. This means that the higher the level of cholesterol in the blood, the lower the risk of developing colorectal cancer. The link between blood cholesterol levels and colorectal cancer risk were observed to occur regardless of statin use.

"Although the risk of colorectal cancer was lower in statin users versus non-users, when we compared those who continued statin therapy versus those who discontinued the therapy, such that each group shared the same indication for statin therapy, there was no difference in risk," said Ronac Mamtani, MD, MSCE, an assistant professor of Hematology/Oncology from the Perelman School of Medicine at the University of Pennsylvania and the Abramson Cancer Center, and lead author of the study, in a statement.

For the study, researchers compared statin use and blood cholesterol level between 22,163 patients with colorectal cancer and 86,538 patients without colorectal cancer, which served as the control, from a database of electronic records of more than 10 million patients from United Kingdom's primary care practices.

The researchers then discovered that statin-users have lesser risk of colorectal cancer compared to non-users. But they didn't find any significant difference in the colorectal risk between those patients who continued to use statin and those who have stopped taking the drug.

They also found out that every 1 mmo/L increase in the total blood cholesterol level reduces risk of developing colorectal cancer by 10 percent. Additionally, researchers have observed a significant drop in the total serum cholesterol of patients at least a year before they are diagnosed increase the risk of having colorectal cancer by 1.25-fold and 2.36-fold in users and non-users of statin respectively.

With these findings, researchers have set their sights on the potential of blood cholesterol levels as a marker for an early diagnosis of colorectal cancer.