Another difference between older and newer studies is that the type of patients treated with the ketogenic diet has changed over time. When first developed and used, the ketogenic diet was not a treatment of last resort; in contrast, the children in modern studies have already tried and failed a number of anticonvulsant drugs, so may be assumed to have more difficult-to-treat epilepsy. Early and modern studies also differ because the treatment protocol has changed. In older protocols, the diet was initiated with a prolonged fast, designed to lose 5–10% body weight, and heavily restricted the calorie intake. Concerns over child health and growth led to a relaxation of the diet's restrictions.[18] Fluid restriction was once a feature of the diet, but this led to increased risk of constipation and kidney stones, and is no longer considered beneficial.[3]
"Not only do I love IQ BAR's all-natural taste and smooth-yet-crunchy texture, but also its ingredient list," says registered dietitian Kathleen Wright, R.D. IQ Bars are loaded with healthy fats, fiber, and protein from plant-based foods like nuts, seeds, and fruit, she says. This low net carb, high-fat treat promotes sustained energy throughout the day and makes a perfect keto-friendly choice for snackers on the go. (But read this first: Is It Healthy to Eat a Protein Bar Every Day?)
The main criticisms include fears about fat intake and the process of ketosis.The argument over whether saturated fats are unhealthy has been settled in the research literature (they are not). If you need more info, there are several good books to read on this subject.  For more information about the type of fats to eat, see the saturated vs unsaturated fats page.  The right side column on that page has books which provide more information.

Note: Are you a vegetarian or vegan and want to go on a ketogenic diet? It’s still possible! Just keep in mind that the dietary restrictions can sometimes be a little bit intense. Make sure to plan ahead and prepare to aid your success. To help out, we’ve published articles (with 7 day meal plans included) for both the vegetarian ketogenic diet and the vegan ketogenic diet.
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