I think if you and your daughter understand the limitations of what this sort of diet is, (sounds like Lighter Life) and what some of the unwanted side affects can be (smelly breath, for example), very high re-put on rate that doesn't help somebody suffering with existing poor body issues then at least it's going into it with full knowledge.
It's a very clever marketing campaign and it WILL deliver the results but there is ABSOLUTELY no room to introduce any of the poor eating habits during the programme. Once you stop the programme, if you introduce those bad habits again it's very likely that the weight will go back on (and how!) and that losing weight again will take time as the metabolism stabilises.
If I were going to do what your daughter wants to do, this is what I'd do and in the order I'd do it:
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- Work out my priorities, ie. - fit in my dress and play with my children.
- Confirm in my head what I will have to give up - eating food with the family - or at any other time - in the normal way.
- Realise that I'd have to find time to exercise and tone my body because with that dramatic weight loss, I'd have loose skin. At 26 I'd be able to 'snap back' BUT it comes at a cost so, like it or not, fit or not, I'd have to look at something like Jillian Michaels' very effective DVDs. That's half an hour a day, no messing, amusing and easy exercise it is NOT.
- Accept that counselling is NOT optional, not even for my childrens' 'wants'. Their needs their father will have to take care of. For me to succeed, I'd have to be prepared to take a step back and not use the children as an excuse at ANY point.
- Coming to terms with my weight loss... like giving up smoking, the brain plays 'tricks'. When the body senses 'starvation' or something akin to drastically different eating habits, it releases 'cravings' (whatever chemicals those are) to encourage eating. I'd have to be prepared to FOLLOW THE PLAN COME WHAT MAY, there is no OUT, only a definite fail. That's why the counselling is so important.
- Telling my family and getting their buy-in - this is important because I wouldn't be eating normally anymore, not for the duration.
- EXIT Strategy. The plan isn't for life. I would reach a crossroads at the end of it. What would I do? It's all well and good to say that I would switch straight to healthy eating and step up my exercise as I get fitter. The reality, from this plan, is that I would switch to my old habits - either immediately or by degrees. The net result would be terrible.
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Particularly for the long term, OP, when your daughter has the nice photos, what does she want then? What is she prepared to do for up-keep?
I know that you're prepared to do whatever it takes to make her happy but I think you need to consider also 1) you can't do it for her, and 2) it will possibly break your heart if whatever caused the weight to pile on in such a short time hasn't specifically been addressed. Putting on weight very fast can put even more pressure on organs and joints than gaining it slowly and steadily.
Make no mistake, your daughter is under significant pressure as the wedding has been paid for. It would be a very good idea, if you can afford it, for she and/or you to see if you can find a specialist in the field to just talk to, without judgement, but letting you know the pitfalls as well as the highlights.
You will need support yourself, OP - I think you should have a good chat with your husband to see what his worries and fears are. You need to be united in your decision and at peace with it.
Good luck and best wishes, OP, you sound lovely. 