Like all ketogenic diets, the Atkins diet functions via caloric control through restricting carbohydrate intake. Particularly during the early stages, or the induction phase, carbohydrates, other than fiber, cannot become part of your diet. Consuming an easily digested sugar or saccharide such as maltodextrin will result in dietary disaster unless you do it at just the right time. The Atkins diet focuses on burned ketones, or fatty acids as your primary source of energy. While a small amount of amino acids and sugars will be burned at all times, when the bulk of your energy is coming from ketones, you are said to be in ketosis.

Maltodextrin is a simple and easily digestable sugar. It is sometimes used as a food additive, and often added to post-workout supplements to refill sugars depleted during training. Maltodextrin is normally made from corn starch, and is often used as an artificial sweetener. It is also used in the brewing process of many alcohols, including beer. If maltodextrin is manufactured from wheat instead of corn starch, which is a common process, it may contain significant amounts of gluten.

Maltodextrin by any name and process is a sugar, and needs to be avoided for most purposes while on the Atkins diet. Consuming sugar in any quantity not only knocks you out of ketosis, the more you consume the longer it takes you to get back into a ketogenic state. In most scenarios, avoid maltodextrin in all forms, as it not only limits your ability to remain in ketosis, it is primarily a source of empty calories. The sole exception being immediately after a workout.

The only time it is safe to consume maltodextrin while on the Atkins diet is immediately after a workout, and even then you should not consume much. Intense resistance training or exhaustive endurance exercise will deplete the sugar you store in your muscles, in addition to your blood sugar. Following a workout, consuming a small amount of simple sugar, such as maltodextrin, will refill depleted muscle gylcogen without greatly disturbing your ketogenic state. A small amount of protein consumed in conjunction with maltodextrin helps promote recovery from training, according to a 2007 study in the "Journal of the International Society of Sports Nutrition."