There is no shortage of commercial weight loss programs like Jenny Craig, Lite n Easy, Weight Watchers, Take Off Pounds Sensibly (TOPS), and Overeaters Anonymous (OA). The basic premise for people on these diets involves choosing from their low calorie and quite healthy food options, then you pay and they send it out to you.
Usually they have a staff member who calculates how many calories you need to have to lose weight, and they ensure you have adequate amounts of the major macronutrients.
So what is the evidence? Which ones work?
There is always caveats with evidence – what I see in the clinic and what the big trials tell us. In 2016 a team of Johns Hopkins researchers reviewed 4,200 studies for solid evidence of their effectiveness but concluded only a few programs have shown that their users lose more weight than those not using them and just dieting by themselves. The only two programs that had good evidence for their use after a year were Weight Watchers and Jenny Craig, with some promising but not clear benefit for the Nutrisystem diet.
Though even those who did lose weight only lost 3-5% more on the program that those not on the program and just followed their own diet with a supportive health professional.
However, the major pro is the convenience factor because meals are supplied and that is very good for some people. The downside of this though is that at some point you still need to learn how to create healthy eating and cooking habits yourself. So initially these programs can be a great support but eventually turn into a handicap.
Their major downside is they can be very expensive. Costs of the commercial programs, which ranged from zero for Web-based weight-loss apps to between $570 and $682 per month for programs that require clients to buy replacement meals. The average was about ~$150/week/person depending on the number of days and meals, which is about ~$5-13AUD per meal depending on the meal, dinner being the most expensive.
So in the end you have to decide. For some the cost is too much and for some it is extremely worthwhile and effective. I work with patients of all different backgrounds and some find it very hard to prepare their own meals for a variety of reasons and for them have seen these programs work well.