New research published at PlosOne on-line provides evidence that supplementing with creatine monohydrate (CrM) and conjugated linoleic acid (CLA) induce greater strength and muscle gains and a greater reduction of body fat (especially abdominal fat) than exercise alone.

This study was performed by engaging older adults, who had never strength trained but were relatively healthy, in a controlled exercise program for six months.  About half the group took a placebo and the other half took creatine and CLA supplements, both with no change in dietary habits. 

The scientists report that all the participants experienced better functional ability and strength as a result of the resistance exercise training. However, those who took the CrM and CLA combination enjoyed better results - they had better gains in muscle endurance, superior increase in fat-free mass and a larger drop in the percentage of body fat, compared to the placebo group.

I consider these supplements to be safe and effective when used properly.  It is important to note that there were no adverse health effects in this study and that all the liver, blood, and serum tests were reported as normal or no change.