Link to the article: https://pubmed.ncbi.nlm.nih.gov/31879752/
Intermittent fasting (IF) and Paleolithic (Paleo) have been studied before and found to be effective in controlled studies. The study gave 250 overweight patients the option of Mediterranean, IF, or Paleo diets. Most chose IF. Many patients did not stick to their diet over the course of a year. On average there was weight loss if patients stuck to their diet. However, between IF, Paleo, and a Mediterranean diet, no statistical differences in weight loss could be determined.
TL;DR Intermittent fasting (IF) and Paleolithic (Paleo) are effective in controlled studies, but without oversight, people tended not to stick with the diet. Those that did had reduction in weight overall