High BMI may improve some cancer treatments, but it's complicated

A new study investigates the 'obesity paradox,' which refers to the fact that excess body fat may be a cancer risk, but could also improve a patient's response to cancer treatment in certain cases. The new research comes out of Flinders University, where scientists looked into clinical trials involving an immunotherapy treatment used for non-small-cell lung cancer called atezolizumab. Patients who had higher BMIs were also found to have better responsiveness to the drug.

Being overweight and obese is considered a cancer risk due to the inflammation it causes, among other things. The link between excess body fat and cancer is a strong one, spurring public health campaigns that advise the public about this risk. However, in certain cancer cases having a high BMI may improve the outcome of the treatment protocol.

The new study out of Flinders University found that across four different clinical trials, patients who had a high BMI and were receiving the treatment atezolizumab experienced a 'significant reduction' in mortality. In this case, a high BMI was one exceeding 25 kg/m2.

A total of 1,434 people participated in the research, of which 49-percent were listed as normal weight, while the remaining 34-percent were overweight and 7-percent were obese. Dr. Ganessan Kichenadasse, the study's lead investigator, explained:

We need to do further studies into the possible link between BMI and related inflammation, which might help to understand the mechanisms behind [the] paradoxical response to this form of cancer treatment ... Our study provides new evidence to support the hypothesis that high BMI and obesity may be associated with response to immunotherapy.

Of course, the link between cancer risk and obesity remains. Excess body fat is a known health risk and may be the catalyst for a number of serious, chronic health conditions, including high blood pressure, heart disease, type-2 diabetes, autoimmune conditions, high cholesterol and triglycerides, and much more. Public health organizations advocate for weight loss in order to help protect one's long-term health.