The diet was designed to make it difficult for a particular gut bacterium to thrive.
It worked, because after 23 weeks, the population of that bacterium had gone from 35% to zero.
Perhaps coincidentally, the man lost 51 kilos, despite not exercising.
Or just perhaps, the hypothesis that gut bacteria can do other sorts of harm, not just give you ulcers, may have some truth. We'll have to see more and larger studies, but the general hypothesis that the modern epidemic of obesity may indeed be just that - a bacterial epidemic that anyone can catch - is looking more plausible. The high sugar high refined starch Western diet may be to blame, but I'm wondering how much that is due to it being what the enterobacter likes rather than its actual calorie load. And I wonder it's why diets that are at first sight illogical are effective.
New Scientist article (may require registration)