As far as I know, and Im not really an expert, Ill explain my understanding of it. They are similar in many ways
Lipotrim is prescribed by a GP or pharmacist, it cannot be bought anywhere. It is used under very close supervision with the above people. The Lipotrim programme comprises three phases, the weight loss phase during which patients can be expected to lose weight at a consistent rate of around one stone (6.4kg) per month. This is accomplished with specially designed total food replacement nutrient complete formula meals. This is followed by a very critical transition phase, where traditional foods are reintroduced according to a structured schedule. The third phase, maintenance, is lengthy but the most ordinarily neglected aspect of obesity management. Maintenance involves ordinary foods. Patients are educated to select and prepare foods with very low fat content. Lipotrim formula foods can still be available to patients during the transition and maintenance phases of the programme, but still require positive release from the doctor. Without proper assistance with maintenance, most patients will regain the lost weight. The recent addition of a range of maintenance products which do not require medical assistance has been of substantial help in aftercare.
CD
Has different stages and costs no less than £32.55 per week, Sole source which is meal replacement then add a meal every 4 weeks, then maintenence and stabalisation in different stages, or you can start off on a 790 calorie diet with them too.
Lighter life
Is the one I know least about, as far as I can tell it offers much the same as CD but with the added bonus of counselling with regards to food.
Hope this helps, I am on CD but there are many on here that have followed both, the main one that springs to mind is icemoose, aka mike, you could message him to ask his opinion. If I am wrong about any of this info im sorry!
If you need anymore help just let me knowx