Noddy; the realization of the depth of 'trial' that some are subjected to daily, gives those of us who seem to possess reasonable health, great appreciation, and extreme nervousness!
on the subject of 'diet', i would like to add that the popularity of 'low carb.' diets, Atkins, and the like, is based upon the sad case that physical activity is waning in the general population, a circumstance within which cutting down on carbohydrates makes sense. However, the elevated protein intake of such diets opens the door to many more dangerous situations than are exacerbated by excess weight!
The answer lies in increasing the level of activity in small but constant stages, and maintaining it; rather than trying to create a synthetic resizing, based upon poor nutritional choices!
Consult an experienced nutritional expert first, and a competant physician second (and self educate with a broad range of critically approved text), before subjecting your body to any 'extreme' plan.