My 18-year-old son started fasting yesterday. Just out of the blue, he said he was going to fast for a week and only drink juice or milk for “lows.” What are the risks involved?

In general terms, the risk for your son could be accelerated ketoacidosis. Starvation and/or other related dietary measures (such as the Atkins Diet) leads to the production of ketones. Thus, these dietary maneuvers are sometimes referred to as ketosis-prone diets. The absence of insulin, as in type 1 diabetes, also leads to the production of ketones. Why do the ketones develop? In large part, they are due to the natural metabolism of fat as starvation (and insulin deficiency) leading to the use of fat for energy.

In the patient with type 1 diabetes who receives inadequate insulin, the process of ketosis can progress to ketoacidosis, which can be fatal. If your son plans to use this dietary plan as a means to by-pass the need for insulin, he will not be doing himself any favors and it could be dangerous. Having said that, in the years before the discovery of insulin, starvation diets were part of the therapy for patients with diabetes. Such diets, while probably prolonging life, were not without consequence (starvation) but were extremely strict with little or NO carbohydrates allowed.

Your son has gotten some bad information or has poorly interpreted information he has received. He needs to talk with his pediatric endocrinologist! In the meantime, if he is pumping, watch out for HYPOglycemia. If he stops pumping (but is consuming some carbohydrates), watch out for what might be stubborn DKA!

DS