For the record, a meal replacement is not a ‘protein shake’ – a meal replacement is a scientifically formulated product that contains similar macronutrients to that of a meal (20-30g total carbohydrate) as well as a full micronutrient profile with far fewer calories than that of a meal. Meal replacements were originally formulated and used with patients who were in need of rapid weight loss prior to surgery, when completely replacing all meals controlled calorie and carbohydrate intake to such an extent that the patient was put into ketosis and were able to lose weight rapidly.
While still used for this purpose, meal replacements are also commonly used on many ‘diet’ programs with the same goal, helping individuals to control calorie intake as well as being used as a meal option for meals which are commonly missed, such as breakfast.
Being trained as a dietitian, I was of course taught by academic types that as a nutritionist the focus should always be on fresh, healthy, natural food and using such products was really only a good option for those who were in desperate need of weight reduction under medical supervision ie as a dietitian always promote ‘real food’.
It was not until I began working at The Children’s Hospital almost 10 years ago solely with overweight and obese children and teens that I began experimenting with these products. In client cases in which I had an overweight teen that generally skipped breakfast, I began using these products as a breakfast alternative. The teens were often happy to ‘drink’ their high protein breakfast and almost to my disbelief we started to get positive weight loss results with these teens, even better than we got when we used standard breakfast options of cereal or eggs on toast.
It is was this observation that lead me to approach a supplier of meal replacement products in Australia to look at supplying product for a research trial and ultimately an endorsement of these products as I do get positive results using them in clinical practice for weight loss.
This is not to say that I recommend meal replacements for all of my clients but I do find that for breakfast skippers, busy executives who often miss meals and for those who need a weight loss kick-start after finding themselves on a tough weight loss plateau that meal replacement products can support weight loss.
To this day I still do not really know why these products work so well, but I do know that if I nutritionally model breakfast with a similar macronutrient ratio to than of a meal replacement that I do not get the same weight loss results and all I can put this down to is the calorie restriction even if it is only a 100 calorie difference between the standard breakfast option and a meal replacement product.
Then of course there is the ongoing aggression that arises whenever sugar is spied on a nutrition label. Meal replacements tend to be relatively high in sugars as a high protein drink will taste pretty ordinary without some sort of sweetener or sugar base to sweeten it up. This appears to have no negative outcome on insulin release or weight loss in these products simply as the high protein load of these products is likely to be buffering the sugar load, particularly as part of a tight calorie control.
Of course it would be amazing to have a randomized controlled trial that really investigates why and if these products really do work but I unfortunately do not have the 3 to 5 years an RCT takes to justify using these products, I need to get results with my weight loss clients now.
As is the case with every option in nutrition and life in general people can ultimately make their own decisions when it comes to the way they choose to go about weight control. It is not my job to tell everyone what they should do for weight loss. Nor is it to constantly defend why I choose different options working with clients towards sustainable weight loss – this is the art of my own clinical practice but if asked I can give my best scientifically informed opinion on what I find works well in practice and that is what I have done in the case of meal replacements. Whether or not you agree is up to you but there really is no need to get so nasty about it.