Hi Karen, he donates all the income from the FMD towards more research so doesn't benefit financially from it at all from what I have read. For example "Longo created a company, L-Nutra, to market the diet, and retains majority ownership. He intends to funnel any personal profits into a nonprofit to fund research."

https://www.statnews.com/2017/06/13/fasting-diet-valter-longo/