I mean she lasted 10 years on the diet, is the diet really to blame or is cholera to blame? Like I guess maybe she didn’t wash a few of them thoroughly enough and caught it? It does raise a lot of questions.
The answer is “Yes”. And no it doesn’t raise a lot of questions, tbh.
If you eat badly - no matter which way - your body is automatically weaker and less able to withstand hardship.
Make it weak enough, and then find the right hardship, and congralations, you are now dead.
Note that both of these are on a sliding scale: You can eat 100% healthy, a hardship such as a nuclear bomb exploding while pressed on your eyeball will still do you in. You can have the worst of diets for years, and as long as nothing at all immediately threatens you, you’ll survive. And somewhere in between, Zhanna managed to make her body weak enough that a simple cholera infection did her in.