Can Your Metabolic Health Affect Your Colorectal Cancer Risk?
A new study involving normal-weight postmenopausal women found that poor metabolic health was associated with an increased risk for colorectal cancer
About 4.4 percent of men and women in the United States will be diagnosed with colorectal cancer at some point during their lifetime, according to statistics from the National Cancer Institute.
Each person’s risk of developing colorectal cancer is linked to numerous genetic, environmental, socioeconomic, and lifestyle factors, according to the authors of a new study that was published recently in Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research.
The study showed that normal-weight postmenopausal women who were metabolically unhealthy had a significantly increased risk for colorectal cancer compared with those who were metabolically healthy.
Even though poor metabolic health is usually associated with obesity, 30 percent of normal-weight adults are believed to be metabolically unhealthy worldwide, says the lead author of the study, Xiaoyun Liang, MD, PhD.
Dr. Liang, who is an associate professor at Beijing Normal University in China, adds that the results of the study highlight how important it is for women to be aware of their metabolic health status, which can be assessed using standard clinical tests.
And she added: "Recognition that normal-weight women who are metabolically unhealthy may have an increased risk for colorectal cancer could result in more timely use of preventive interventions and reduce the burden of this deadly disease."
Metabolic health is often assessed by measuring waist circumference, blood pressure, and levels of triglycerides, glucose, and high-density lipoprotein cholesterol – HDL-C, so-called "good" cholesterol – in the blood. People have metabolic syndrome if they have three or more of the following: elevated waist circumference, elevated blood pressure, elevated levels of triglycerides, elevated levels of glucose, and low levels of HDL-C. In this study, people were considered metabolically unhealthy if they had two or more of those factors excluding elevated waist circumference.
For the study, Liang and colleagues used data from 5,068 postmenopausal women enrolled in the Women’s Health Initiative. All the women were classed as normal weight based on having a body mass index (BMI) from 18.5 kg/m2 to <25 kg/m2; 33.7 percent of them were metabolically unhealthy.
During a mean follow-up time of 14.3 years, 64 of the 3,358 women who were classed as metabolically healthy were diagnosed with colorectal cancer and 50 of the 1,710 metabolically unhealthy women. After adjusting for numerous factors that affect colorectal cancer risk, the researchers calculated that women who were metabolically unhealthy had a 49 percent increased risk for colorectal cancer relative to with those who were metabolically healthy.
The researchers also found that women with metabolic syndrome had a more than two-fold higher risk for colorectal cancer relative to those who were metabolically healthy.
It is important to remember that this study involved only postmenopausal women. Therefore, the study’s funding can be generalized only to postmenopausal women and not men or younger women, said Dr. Liang.
Another limitation of the study, she explained, was that BMI and components of metabolic health were measured only at the time of enrollment in the Women’s Health Initiative and possible changes over time could not be considered in the analysis. The study was supported by a grant from the National Cancer Institute.