Some people eat three times a day and occasionally snack in between (note that frequent snacking could mean that you’d benefit from adding fat to your meals, to increase satiety). However, there’s some evidence that frequent snacking isn’t wise when trying to lose weight. Some people only eat once or twice a day and never snack. Whatever works for you. Just eat when you’re hungry.
When you eat less than 50 grams of carbs a day, your body eventually runs out of fuel (blood sugar) it can use quickly. This typically takes 3 to 4 days. Then you’ll start to break down protein and fat for energy, which can make you lose weight. This is called ketosis. It's important to note that the ketogenic diet is a short term diet that's focussed on weight loss rather than the pursuit of health benefits.
Initial human studies that compared fasting every other day to eating less every day showed that both worked about equally for weight loss, though people struggled with the fasting days. So I had written off IF as no better or worse than simply eating less, only far more uncomfortable. My advice was to just stick with the sensible, plant-based, Mediterranean-style diet.
If you’ve decided to move forward in trying the keto diet, you will want to stick to the parameters of the eating plan. Roughly 60 to 80 percent of your calories will come from fats. That means you’ll eat meats, fats, and oils, and a very limited amount of nonstarchy vegetables, she says. (This is different from a traditional low-carb diet, as even fewer carbs are allowed on the keto diet.)
After about two to seven days of following the keto diet, you go into something called ketosis, or the state your body enters when it doesn't have enough carbs for your cells to use for energy. That's when you start making ketones, or organic compounds that your bod then uses in place of those missing carbs. At this point, your body also starts burning fat for more energy, says Beth Warren, R.D., founder of Beth Warren Nutrition and author of Living A Real Life With Real Food.
Frederick F. Samaha, M.D., Nayyar Iqbal, M.D., Prakash Seshadri, M.D., Kathryn L. Chicano, C.R.N.P., Denise A. Daily, R.D., Joyce McGrory, C.R.N.P., Terrence Williams, B.S., Monica Williams, B.S., Edward J. Gracely, Ph.D., and Linda Stern, M.D., “A Low-Carbohydrate as Compared with a Low-Fat Diet in Severe Obesity,” N Engl J Med 2003; 348:2074-2081. http://www.nejm.org/doi/full/10.1056/NEJMoa022637.
Make sure that you don't get hungry by eating small portions throughout the day at regular intervals. Between your meals, eat a 150-calorie snack to keep your metabolism burning and to stave off hunger. Be sure that you don't eat a fattening snack such as sweets or crisps. When you're hungry, your body conserves calories and slows down your metabolic processes.
If you need to eat more or fewer calories per day, you can adjust accordingly by simply taking out or adding a bit more of the ingredients already included in a recipe. For example, adding/removing a tablespoon of olive oil or butter will add/remove about 100 calories. If you like or dislike certain recipes, feel free to shift things around. Make sure to keep an eye on the calories so you’re still falling within an acceptable range of your daily goal.
Obviously, it’s still possible to lose weight on any diet – just eat fewer calories than you burn, right? The problem with this simplistic advice is that it ignores the elephant in the room: hunger. Most people don’t like to “just eat less”, as it may result in having to go hungry forever. Sooner or later, a normal person will likely give up and eat, hence the prevalence of “yo-yo dieting”. While it should be possible to lose weight on any diet, some appear to make it easier and some to make it much harder.