If you check out all the "Magic Pill Debunking" videos on YouTube, most of them were produced by butt hurt vegans. And some of those vegans are extremely anxious about anybody challenging their beliefs, it's almost like a cult. Worse thing is , this documentary does not even mention vegan / vegetarian style of eating in a bad light. Part of healthy Ketogenic diet actually IS eating a lot of vegetables such as broccoli, cauliflower, cabbage, asparagus, and other plant you would typically find in a green leafy salad... They simply take offense to the protein part of ketogenic diet, and cite the health risks of low carb / high protein diet, without realising, that it is NOT ketogenic way of eating. Ketogenic diet macronutrient ratio is around 20g/day or around 4-5% carb (not LOW carb , maybe NO CARB to VERY low carb) and MEDIUM protein intake. If those vegans and some but hurt dietitians took time and look at the latest SCIENCE behind Ketogenic diet, they would see how it's beneficial to any human being. It's not just some average , one of many diets that will fade, but a fundamental change in metabolism type. While on Keto you have all the benefits of fasting, it does help to slow down / stop the growth of cancer cells (as they can't use ketones as fuel) , your mitochondria can effectively convert ketone bodies to energy even if imflamations are present, which it cannot do very well with glucose, burning ketones produces much less oxidative stress which means less free radicals in the body, etc, etc, can't go into too much detail here. None of those critics either here or in those youtube videos , have any deeper knowledge of Ketogenic diet, they make their OWN assumptions of what it is, but so far I haven't seen ONE critic that actually properly understand what this diet / way of eating is about.
Check out PhDr Dom D'Agostino on youtube, or Dr Berg for example, for some deeper understanding of this diet and it's benefits.