“We do not recommend the diet,” he says. “It works for weight loss, and the liver insulin resistance we observe might be transient. But the diet is simply not necessary and probably not the best choice for weight loss,” he says. “Ketogenic diets are often very low in fiber, which may have bad effects on gut health and overall health, especially over a long term. Diets high in fiber and low in fat work equally well or better than low-carb plans, in many studies, to achieve weight loss and lower glucose intolerance.”
The first meta-analysis worth noting collected the data from 10 randomized trials comprising 1376 participants in total.  After analyzing the research, a key relationship emerged between dietary carbs and blood sugar levels. In short, the researchers described their finding thus: “the greater the carbohydrate restriction, the greater glucose lowering…” 
And it’s not just this study, either. Several other studies have found that keto leaves rodents unable to process carbs, leads to insulin resistance, and, more long-term, causes non-alcoholic fatty liver disease, which is when your liver accumulates lots of fat and begins to shut down. Triglycerides and inflammation go way up, too.
People claiming huge benefits of these supplements – despite the lack of solid scientific support – may sometimes have a financial reason to believe in the supplements. Some of these products are sold under a multi-level marketing arrangement, where sales people are paid based on commission. For example, the company Prüvit sells drinkable ketones, called KETO//OS with a multi-level marketing structure.