There's a net of dieting resorts around Poland doing "Dieta Dąbrowskiej" among some other health-oriented stuff. In essence it's calorie restriction on veggies

There's a net of dieting resorts around Poland doing "Dieta Dąbrowskiej" among some other health-oriented stuff. In essence it's calorie restriction on veggies for 2-6 weeks at a time supplemented with blood tests and physical activity. She (Dąbrowska) states that it resets the immune system, restricts cancer growth (or even puts cancers into recession), helps with diabetes and cures food intolerance. Proof for it is provided as "I've seen people that improved". I'm highly skeptical about it as my vegan-celiac-fit family part got hyped for it and went through a 3 week run. They came back with anecdotal self-healing miracles. The diet is around 600-700 kcal a day, low on sugar. Supposedly it stimulates autophagy giving all of the stated benefits (on top of cleansing out "toxins"). As a side note I found that food intolerance is in fashion recently. There's one (!) test offered in my area for it called the Food Detective (made by Cambridge Nutritional Sciences Ltd.). I'm highly skeptical of it too as there's no competition and I couldn't find any studies confirming it's effectiveness. My main concern is the potential impact on the brain. I vaguely recall some study observing neuron loss during extended periods of starvation. Also having some sensible studies to back it up (or debunk it) would be nice.