I don’t think it’s practical to be in ketosis or maintain total adherence to the keto diet, or any other diet for that matter, 24 hours and 7 days a week for the rest of your life. It really wouldn’t make life enjoyable either to miss out on cakes, candies, breads, pasta, and other foods that will knock you out of ketosis.
I do think, as a lifestyle, it is sustainable over the long term. I’ve been living it for more than 20 years. During the holidays or other special occasions I eat like any normal person. Life is to be lived after all and denying yourself certain foods will only lead to a return to poor eating habits. There is nothing wrong with the occasional indulgence, especially once you’ve reached your body type goals.
A long-term ketogenic diet could lead to micronutrient deficiencies as the years go by. Although a keto diet can be loaded with highly nutritious vegetables, fats, and proteins; it is still quite a restrictive diet. This means you may start eating the same limited foods again and again. This absence of food variety can disturb your micronutrient consumption.Inquirer.net
A good way to curb micronutrient deficiency is to eat a lot of low-carb veggies. Also, alternate the types of meat you eat.