The easiest macro to calculate in the ketogenic diet is fat. Once you've got your carbs and protein set, simply fill the rest of your daily calorie needs with fat sources. If you find yourself wanting to gain a bit of weight, add approximately 500 calories, or 55 grams. If you want to lose weight, cut down on your fat intake by 200-500 calories, or 22-55 grams.
Diarrhea can also be due to a lack of fiber in the diet, says Kizer, which can happen when someone cuts way back on carbs (like whole-grain bread and pasta) and doesn’t supplement with other fiber-rich foods, like vegetables. It can also be caused by an intolerance to dairy or artificial sweeteners—things you might be eating more of since switching to a high-fat, low-carb lifestyle.
I was a Corpsman (not a corpse-man as some recent somewhat fanatical president would say), and I can tell you many stories of Marines and Sailors who maintained restrictive diets (aka picky eaters). Most obvious was lack of sustaining energy (hypoglycemia) at mile 15 (with 80lbs of gear including a 6.5lb rifle and 200 rnds of ammo, etc.) and depletion of essential vitamins, electrolyte imbalance. They were always the first to collapse and have to hear me scold “see I told you so.” An IV of D5W usually does the trick (D is for dextrose, OMG!)
When in the hospital, glucose levels are checked several times daily and the patient is monitored for signs of symptomatic ketosis (which can be treated with a small quantity of orange juice). Lack of energy and lethargy are common but disappear within two weeks.[17] The parents attend classes over the first three full days, which cover nutrition, managing the diet, preparing meals, avoiding sugar and handling illness.[18] The level of parental education and commitment required is higher than with medication.[43]

H. Guldbrand, B. Dizdar, B. Bunjaku, T. Lindström, M. Bachrach-Lindström, M. Fredrikson, C. J. Östgren, F. H. Nystrom, “In Type 2 Diabetes, Randomisation to Advice to Follow a Low-carbohydrate Diet Transiently Improves Glycaemic Control Compared with Advice to Follow a Low-fat Diet Producing a Similar Weight Loss,” Diabetologia (2012) 55: 2118. http://link.springer.com/article/10.1007/s00125-012-2567-4.

The remaining calories in the keto diet come from protein — about 1 gram (g) per kilogram of body weight, so a 140-pound woman would need about 64 g of protein total. As for carbs: “Every body is different, but most people maintain ketosis with between 20 and 50 g of net carbs per day,” says Mattinson. Total carbohydrates minus fiber equals net carbs, she explains.
The ketogenic diet is a medical nutrition therapy that involves participants from various disciplines. Team members include a registered paediatric dietitian who coordinates the diet programme; a paediatric neurologist who is experienced in offering the ketogenic diet; and a registered nurse who is familiar with childhood epilepsy. Additional help may come from a medical social worker who works with the family and a pharmacist who can advise on the carbohydrate content of medicines. Lastly, the parents and other caregivers must be educated in many aspects of the diet for it to be safely implemented.[5]
One area where food tracking can be especially helpful, though, is ensuring that you're hitting the right ratios of macronutrients—protein, carbs, and fat. "The most researched version of the ketogenic diet derives 70 percent of calories from healthy fats, 20 percent from protein, and only 10 percent from carbs," explains Charles Passler, D.C., nutritionist, and founder of Pure Change. "In the ideal world, each keto meal and snack should have that same (70/20/10) ratio of macronutrients, but studies have shown that you'll still achieve great results even if each meal varies slightly from that ratio, just as long as you don't exceed 50 grams per day of carbs, or eat those carbs in one sitting," says Passler. In order to achieve these ratios without a preset meal plan from a dietitian or doctor, some food tracking is probably going to be necessary. But once you get the hang of things, you may not need it anymore.
Staying in Ketosis long-term: Chronic Ketosis can cause fatigue, muscle soreness, insomnia and nausea. "Unless you have a medical condition that requires you to stay in Ketosis for long-term, you shouldn't stay in that state for a prolonged period without any carb ups," Mavridis suggests. And if you're a beginner, "it’s recommended that you go through the fat-adaptation phase so that your body becomes accustomed to burning both glucose and fat for fuel," says the nutritionist.
For any individual with diabetes, discussing dietary changes — especially those as dramatic as the ones the ketogenic diet requires — with your healthcare team is essential. Because carbohydrates are broken down into glucose in the blood, cutting carbohydrates from your diet could cause levels to crash rapidly depending on your current medication regimen. Such a change may require significant adjustments to medication and insulin to prevent dangerous side effects such as low blood sugar, called hypoglycemia. (8)
“One of the best meal planning tips I’ve ever received is to structure breakfast and lunch so that you don’t have to think too much about it,” says Emily Bartlett, co-founder of Real Plans. “If you’re okay with repetition, it’s ideal to have a simple selection of recipes for breakfast—including some that can be taken on the go. For lunch, go ahead and use your leftovers with a fresh green salad, and be sure to include a dressing that you really love.”

When you’re eating the foods that get you there (more on that in a minute), your body can enter a state of ketosis in one to three days, she adds. During the diet, the majority of calories you consume come from fat, with a little protein and very little carbohydrates. Ketosis also happens if you eat a very low-calorie diet — think doctor-supervised, only when medically recommended diets of 600 to 800 total calories.
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