On the ketogenic diet, carbohydrates are restricted and so cannot provide for all the metabolic needs of the body. Instead, fatty acids are used as the major source of fuel. These are used through fatty-acid oxidation in the cell's mitochondria (the energy-producing parts of the cell). Humans can convert some amino acids into glucose by a process called gluconeogenesis, but cannot do this by using fatty acids.[57] Since amino acids are needed to make proteins, which are essential for growth and repair of body tissues, these cannot be used only to produce glucose. This could pose a problem for the brain, since it is normally fuelled solely by glucose, and most fatty acids do not cross the blood–brain barrier. However, the liver can use long-chain fatty acids to synthesise the three ketone bodies β-hydroxybutyrate, acetoacetate and acetone. These ketone bodies enter the brain and partially substitute for blood glucose as a source of energy.[56]
Normal dietary fat contains mostly long-chain triglycerides (LCTs). Medium-chain triglycerides (MCTs) are more ketogenic than LCTs because they generate more ketones per unit of energy when metabolised. Their use allows for a diet with a lower proportion of fat and a greater proportion of protein and carbohydrate,[18] leading to more food choices and larger portion sizes.[4] The original MCT diet developed by Peter Huttenlocher in the 1970s derived 60% of its calories from MCT oil.[15] Consuming that quantity of MCT oil caused abdominal cramps, diarrhea, and vomiting in some children. A figure of 45% is regarded as a balance between achieving good ketosis and minimising gastrointestinal complaints. The classical and modified MCT ketogenic diets are equally effective and differences in tolerability are not statistically significant.[9] The MCT diet is less popular in the United States; MCT oil is more expensive than other dietary fats and is not covered by insurance companies.[18]

Net carbs are what we track when following a ketogenic diet. This calculation is pretty straightforward. Net Carbs = Total Carbs – Fiber. For example, one cup of broccoli has 6g of total carbs and 2.4g of fiber. That would mean one cup of broccoli has 3.6g of net carbs. We count Net Carbs  because dietary fiber does not have a significant metabolic effect. 
I never set out to lose a certain amount of weight when I started, I just wanted to be healthy for myself and my kids. In the beginning it was tough, I was used to eating a whole large pizza with ranch for dinner, or 3 grilled cheese sandwiches dipped in barbecue sauce. Veggies were eschewed unless they were a topping on my cheeseburger. I remember my first week I packed a salad with chicken and bacon and blue cheese dressing, and that was pretty good. Then I made some brats and sauerkraut and mustard with a side of broccoli. Hey this isn't so bad. I got in to the habit of picking a protein and a veggie and mix and matching for variety. Chicken, pork chops, brats, steak, and broccoli, Brussels sprouts, asparagus, green beans were my staples. I didn't weigh or count macros, I just avoided the bad carbs and focused on the good. https://philosophyofhealthorg.tumblr.com/