A casual friend of mine (female, 27 years old) has suffered from some kidney stones and other minor problems. hot flashes, low energy, etc.
Her doc is working to isolate the issue, and put her on a 400-calorie per day diet. He believes it will help him to isolate whatever issue she's having internally.
I don't know her all that well, so I didn't want to stick my opinion in there, in case her doc is correct and I'm not. I didn't think 400 calories was enough to sustain life. She's on the diet indefinitely, or at least a month until the next appointment. light-headed, etc, on the first days of the diet.
How can a human function on 400 claories? Is that a dangerous diet? She loves her doc and swears he'd never steer her wrong, and I sure don't have all the details. Are there scenarios where 400 kcal per day is okay?