So this isn't healthy if you want to keep it off long term. Lighter Life will get you close to that result if you stick rigidly to it, but its not for the faint hearted and you need to bare in mind that it is not a long term solution. You would also need to do it 'properly' through a councillor rather than alone (as it won't work). Anything where you don't actually eat isn't great for you psychologically, and often at the end of the programme you will super over indulge to 'make up' for it.
Slow and steady is the best and healthiest approach - having battled with my weight since I was 12/13 I am fully aware... lighter life, cambridge, ww, sw, drugs, non-prescribed drugs (from a quack), slim fast, low calorie, low fat, paelio, Atkins, Dukan... every time I lost and every time I put more back on.
At most I've lost 18lbs over 2 weeks, but I was morbidly obese and had to undertake a liver reducing diet in preparation for wls, and then a further 15-20lbs in the two weeks following.
Try and be realistic with what you are after... if its to make you happy, weight loss often doesn't on its own...