Variations on the Johns Hopkins protocol are common. The initiation can be performed using outpatient clinics rather than requiring a stay in hospital. Often, no initial fast is used (fasting increases the risk of acidosis, hypoglycaemia, and weight loss). Rather than increasing meal sizes over the three-day initiation, some institutions maintain meal size, but alter the ketogenic ratio from 2:1 to 4:1.[9]

The ketogenic diet is not a benign, holistic, or natural treatment for epilepsy; as with any serious medical therapy, complications may result.[28] These are generally less severe and less frequent than with anticonvulsant medication or surgery.[28] Common but easily treatable short-term side effects include constipation, low-grade acidosis, and hypoglycaemia if an initial fast is undertaken. Raised levels of lipids in the blood affect up to 60% of children[38] and cholesterol levels may increase by around 30%.[28] This can be treated by changes to the fat content of the diet, such as from saturated fats towards polyunsaturated fats, and if persistent, by lowering the ketogenic ratio.[38] Supplements are necessary to counter the dietary deficiency of many micronutrients.[18]

Try Googling “TDEE Calculator”. Once you plug in your stats, the site will calculate your total daily energy expenditure. This is a useful guide in determining how many calories to eat. From there, if you are trying to lose weight, just reduce your caloric intake, increase your expenditure (through exercising more), or use a combination of the two.

A review of multiple studies in the journal Nutrients found that ketogenic diets are connected to significant reductions in total cholesterol, increases in “good” HDL cholesterol levels, dips in triglycerides levels and decreases in “bad” LDL cholesterol; there are questions as to whether diets high in saturated fat negate these benefits. The same paper reports that a ketogenic may slightly reduce blood pressure, but science is still very scant on this point.
But there is evidence that low-carb diets may increase metabolism, according to a paper published November 14 in BMJ. Researchers found that overweight adults who lowered carbohydrates and added more fat into their diets burned about 250 calories more each day than people on high-carb, low-fat diets. The study is impressive because it's the largest, most expensive, and controlled study of its kind.
I eat relatively healthy and fairly low carb (I am already gluten free). I am interested in getting into Ketosis for the the health benefits, but am quite thin for a guy and don’t want to lose any weight. I look at the sample diet above and am pretty sure I would drop weight quickly (I consume about 2,500+ calories daily now). I eat 3 meals plus 2-3 snacks (snacks mostly of nuts (with raisins that would have to go), greek yogurt (would switch to plain), peanut butter, cheese and fruit (would need to reduce qty)). Would eating straight up butter be ok for additional calories also once I am in Ketosis?