15 lbs in 2 weeks is really no way healthy. set aside all the scientific findings and just try to think about this analogy, how long did it take for you to build up that weight? i bet you didn't bulk up 15 lbs in 2 weeks because that too is unhealthy. so that goes the same in losing such weight. but if you really would push, i guess i'd agree with the suggestion that you should cut your limbs, you'd even lose more than 15 lbs in that way.