7-Keto isn't exactly DHEA...
7-Keto is a metabolite of DHEA, it doesn't have any hormone properties.
Numerous studies show that 7-Keto can substantially reduce bodyfat (especially when used in combination with guarana) while inhibiting muscle wasting. The studies have shown that 4 weeks using 100-200 mg daily is ideal to notice significant fat loss. It has a 2-4 week half-life, so I only use it for 12 weeks before stopping.
There are zero side effects associated with 7-Keto. But it's very expensive! I use a thermogenic called Lean System 7, which has really worked well at shrinking fat cells.