A systematic review in 2016 found and analysed seven randomized controlled trials of ketogenic diet in children and young people with epilepsy. The trials were done among children and young people for whom drugs failed to control their seizures, and only one of the trials compared a group assigned to ketogenic diet with a group not assigned to one. The other trials compared types of diets or ways of introducing them to make them more tolerable. Nearly 40% of the children and young people had half or fewer seizures with the diet compared with the group not assigned to the diet. Only about 10% were still on the diet after a few years. Adverse effects such as hunger and loss of energy in that trial were common, with about 30% experiencing constipation.
When it comes to starting the keto diet (or any diet for that matter), there's one thing all experts agree on. You *must* have a plan. "Never try to wing a keto diet," says Julie Stefanski, R.D.N., C.S.S.D., L.D.N., a dietitian based in York, PA, who specializes in the ketogenic diet. "Set a start date and get prepared by reorganizing your pantry, planning out meal and snack options, and purchasing appropriate foods and dietary supplements," she says. "The biggest reason people have a hard time sticking with keto is that people don't have enough interesting foods to turn to, and high-carb favorites win out over good intention. If you didn't buy foods at the grocery store that fit the guidelines, there won't be an easy option in the fridge when you really need it." (A great place to start is this List of High-Fat Keto Foods Anyone Can Add to Their Diet.)
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. 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.
As you transition from three meals to two meals or even to one meal a day, you will need to consume more fat. There are all sorts of great desserts you can create that support your weight-loss program. There are also keto bombs, which are fat-rich cookies that can be consumed at the end of the meal to make it incredibly easy to do intermittent fasting. Here are some examples:
Initially you may be surprised that on keto diets you eat less frequently. That’s because the fats are pretty satisfying. But as you normalize and adjust into a ketogenic state, that may change and your appetite may increase. That’s fine and completely normal. Use whatever diet you decide to follow as a starting point – it should be “written in pencil” so that you can make changes along the way. Consider adding an extra meal, marginally increasing the size of the meals or just adding a shake between meals. It’s up to you – just listen to your body. For example for me, I added a low-carb “green powder” shake supplement to my regimen along with either flax seed oil or some nuts in order to satisfy my hunger.