Higher HDL Cholesterol May Cut Colon Cancer Risk
Study Suggests HDL Levels May Be a Useful Indicator of the Risk of Colon Cancer
Colon Cancer, HDL, and Metabolic Syndrome continued...
Blood samples and dietary questionnaires provided at enrollment were compared to determine if major differences existed between the colorectal cancer patients and people who did not develop the cancer.
Overall, the colorectal cancer patients were heavier and reported being less physically active than non-patients.
Just two blood levels -- HDL and another blood fat known as apolipoprotein A-1 (ApoA) -- were found to be associated with colon cancer risk. But after excluding patients with the shortest follow-up, only higher HDL was associated with a reduction in colon cancer risk.
No association was seen between levels of either blood fat and rectal cancer.
The study is published online in the journal Gut.
Low HDL and Inflammation
Bueno-de-Mesquita says low HDL levels may increase colon cancer risk by promoting systemic inflammation. High HDL has been linked in previous studies to high levels of proteins that prevent inflammation.
“It is important to point out that HDL may just be a bystander or indicator of unknown factors that influence the risk for this disease,” he says.
Edward Giovannucci, MD, professor of nutrition and epidemiology at the Harvard School of Public Health, calls the new research “interesting and well done.”
Giovannucci has also studied the impact of metabolic syndrome on colon cancer risk.
“This study suggests that we should look at HDL cholesterol more closely, but I don’t think it is a closed case,” he told WebMD. “Other abnormalities may be as important, or perhaps more so.”
He agrees the possible impact of HDL on colon cancer risk is deserving of further study, but adds that higher levels of HDL may prove to be little more than a marker for metabolic syndrome.
“HDL cholesterol may be acting as a more stable and reliable indicator of metabolic syndrome [than insulin resistance]. But whether it is the direct causal factor requires more work,” he says.