Functions and Health Benefits of Conjugated Linoleic Acid: A Review of Controlled Clinical Trials

The term “Conjugated linoleic acid (CLA)” refers to a class of linoleic acid isomers. During the recent years, scientists have particularly regarded this fatty acid as a functional food. However, the findings of the studies in health benefits of CLA are inconsistent. The purpose of this study was to review the articles that investigated the effects of CLA on different aspects of health.
Controlled clinical trials including human, animal and in vitro studies having been published since 2000 till 2016 in English were searched in PubMed, ISI Web of Science, Scopus and Science Direct databases. Sixty four articles were finally selected to review the results.
Findings of the researche indicated that CLA has an anticarcinogenic function. In some studies CLA had beneficial effects on bone metabolism and it is suggested that CLA may be useful in prevention and treatment of osteoporosis. In addition supplementation with CLA in animal and human models leaded to reduction in body fat mass and improvement in insulin resistance and lipid profile. However, some studies reported adverse effects of CLA intake including accumulation of fat in tissues, elevation of lipid peroxidation and inflammation markers.
Although benefits of CLA intake are shown in several studies, side effects of this fatty acid are reported in other researche. It is necessary to design further studies to more precise investigation of the benefits and risks of CLA.