You can give specific information about what you're offering and still leave something to the imagination. Free in your ad. Free is still a big response booster. Just make sure that you can tie your product into your freebie. Without good health you can't enjoy life to the fullest.
Health related products are a big seller because of the way they're positioned.
Increase your health and everything else in life becomes better. This taps into the need to feel that you are better than others. No one really admits this is what they want, but what do you think all these self-improvement products are all about. Giving you an invisible advantage over others. People will do far more to avoid pain than they will to gain pleasure.