In the beginning, you’ll have to go very low in carbs, around 20 to 30 g a day, to ensure your body goes into ketosis, advises Mancinelli. (Some people call a keto diet anything that limits carbs to less than 50 g a day, though there are various types of keto.) And that can be difficult. When you’re eating a high-fat and very-low-carbohydrate diet, you’re eliminating many foods, including fruit, most dairy, starchy veggies, whole grains, and legumes (and certainly all sugar). It’s difficult and at times uncomfortable.
In the short term, before you begin to lose weight, you may also experience what people call the keto flu, a state that lasts about a week as your body adjusts to the diet. That can include extreme fatigue and foggy-headedness. (Not everyone feels this,Mancinelliallows.) Knowing that ketoflu is a possibility can help you plan the best time to start the diet. You can also mentally prepare for this transition period — reminding yourself that it’s only temporary can help immensely.
For these reasons, “some people won’t be able to stay on it,” says Mancinelli. You should aim to give it at least six weeks. After that, if you feel exhausted or hate eating the food, then the diet is probably not for you. However, if you feel energetic after keto flu symptoms subside within a couple of weeks, which some people report, you may see success with the plan.
