Slim in 6 is a 6 week diet and exercise program from BeachBody.
The program is mostly the work of Debbie Seibers, who has been involved in the fitness industry for some time. Upon joining BeachBody, she went on to develop a number of videos and programs. These eventually culminated in the Slim in 6 program.
Slim in 6 (while still available) has been superceded by Insanity or P90X. See a review of the P90X Fitness and Nutrition Plan here.
Slim in 6 is predominantly a fitness program. Priced at a total of $60-$70, it comprises 5 DVDs, a well-presented printed journal, nutrition guide, and 6-Day diet plan (that is normally sold as a separate item).
You have to be prepared for a lot of cardiovascular exercise and strength training!
It's a big commitment - but many people report success with this format. A strong aerobic component is an excellent part of any weight loss program, but there is a possibility that it could be too much for some. Whilst aerobic exercise can be done daily (or more), with resistance (weight) training you often need more than 24 hours for your muscles to recover.
Like any program advertised using infomercials, there are loads of fitness models to be seen. For a fair number of people, the type of body seen in the ads is unobtainable from a 6 week program.
However if you follow the program there is no doubt that weight loss will occur. Exercising 5 out of 6 days, along with a well-managed diet will lead to fat loss.
Slim in 6 is an good aggressive program (research shows home-based exercise works) - but it will not suit everyone. If you are a person that struggles with motivation to exercise, or are not comfortable going to a gym, or have a difficult schedule - the home-based format may help.
The issue with many of these programs is not they don't work, but that you need to do some habit work in order to keep at it! It can also get frustrating trying to work out in a small living room.