Contemp Clin Trials. 2011 Jan;32(1):69-73.
An urgent need to include risk-benefit analysis in clinical trials investigating conjugated linoleic acid supplements in cancer patients.
Malnutrition and weight loss are common in patients with cancer, both factors could potentially affect the response and tolerance to treatment, decreased quality of life, and thus associate them with poor survival. Conjugated linoleic acid (CLA) is shown to have beneficial health effects in healthy and disease situations including chemoprotective properties in various experimental cancer models. However, the anticarcinogenic property of CLA in animal and tissue culture models could not be confirmed in the Netherlands Cohort Study on Diet and Cancer and a prospective cohort of Swedish women. Cancer patients are already at increased risk of anorexia and there are evidences that CLA suppresses appetite even in healthy individuals. Risk/benefit analysis of CLA supplementation has never been reported before and it is not clear whether any beneficial anti-tumor effect of CLA prevails over its anti-appetite and/or weight lowering side effect in these patients. I suggest that clinical trials investigating CLA supplements in cancer patients, measure appropriate variables such as food intake, weight, and appetite change to yield preliminary data for future trials. I also suggest that data from previous trials that have administered CLA supplements to cancer patients be re-analyzed retrospectively to attempt to find out any effect from routine nutritional measures such as weight, serum albumin and such as those.