As discussed in the Product Review of Weight Loss Supplements, clinical studies suggest that 7-keto DHEA may help you lose weight -- but the evidence is preliminary. People in these studies were put on reduced-calorie diets (and, in one study, an exercise program). Those taking 7-keto DHEA lost more weight than those who took a placebo. 7-keto DHEA appears to increase metabolism, allowing the subjects in the studies (all of whom were obese or overweight) to burn more calories.
However, questions remain for 7-keto DHEA: 1) The clinical studies have been short -- just 1 week to 8 weeks, so the long-term effects are not known, and 2) although 7-keto DHEA has generally appeared safe in these short studies, the long-term side-effects of 7-keto DHEA are not known. Some changes in thyroid function have been noted and one patient experienced a decrease in red blood cells.
For more information about the dosage and side-effects of 7-keto DHEA, as well as quality ratings for two different 7-keto DHEA supplements we purchased, see the Product Review of Weight Loss Supplements, which also includes information about many other supplements for weight loss.