The Nature of the Diet

When a person has GSD type I, the enzyme that converts galactose and fructose to glucose is deficient or missing. This means that any food containing fructose, galactose, lactose, or sucrose should be avoided since it cannot be converted to glucose. In addition to causing increased storage of glycogen, the non-utilizable sugars enter alternative pathways causing an increase in lactic acid, triglycerides, and uric acid.

What to eat then?

With all GSD types it is important to consume adequate amounts of complex carbohydrates in your diet. Failure to eat sufficient carbohydrates can increase the frequency of hypoglycemia. In addition, lack of carbohydrate intake will increase glycogen and/or fat breakdown leading to lactic acid formation (GSD types I and XI).

Uncooked cornstarch is a complex starch that provides a steady amount of glucose because it is digested at a slower rate than other complex carbohydrates. However, the combination of taking cornstarch and eating complex carbohydrates such as whole grain breads and cereals, grains, brown and wild rice, whole wheat pasta, crackers, beans (i.e. garbanzo, pinto, kidney), and starchy vegetables with each meal is important to maintain appropriate blood sugar levels. It is just as important to avoid excess intake of simple sugars such as cookies, cakes, pies, candies, doughnuts, ice cream, soda, Kool-Aid, strawberry Hershey’s syrup, fruit juices, etc. to help keep the liver and muscles healthy.

In GSD I, glucose-6-phosphate cannot be dephosphorylated to free glucose. Managing this condition entails overnight continuous gastric high-carbohydrate feedings; frequent daytime feedings with energy distributed as 65% carbohydrate, 10% to 15% protein, and 25% fat; and supplements of uncooked cornstarch; these are general guidelines and should be supervised by your dietitian.

Here is a sample for a full day schedule for our son (he was around 2 years and 3 months at the time):

  • 5:30AM 1st formula mix feed (9g enfamil powder soy milk + 8.5g Cornstarch. mix with 50ml of water. And give him 25ml through G-Tube while he’s still sleeping)
  • 8AM 2nd formula mix feed (18g enfamil powder soy milk + 16g Cornstarch. mix with 100ml of water. And give
    him 100ml through G-Tube, pump or 4 syringes of 25ml each over 30 min period)
  • 9:30AM oral feed (soup made from a protein like fish, beef or chicken, with some vegetables and a carb like pasta, brow rice or potatoes …, he will usually eat around 20grams, and if he has no appetite, we might give him a small snack like veggie chips and he might eat 2 to 3 sticks)
  • 10:30AM 3rd formula mix feed (18g enfamil powder soy milk + 16.5g Cornstarch. mix with 100ml of water. And give him 100ml through G-Tube, pump or 4 syringes of 25ml each over 30 min period)
  • 12:30PM oral feed (soup made from a protein like fish, beef or chicken, with some vegetables and a carb like pasta, brow rice or potatoes …, he will usually eat around 30grams or if napping, give him 25ml from the following mix: 9g enfamil powder soy milk + 8.5g Cornstarch + 50ml of water)
  • 1:30PM 4th formula mix feed (18g enfamil powder soy milk + 16.5g Cornstarch. mix with 100ml of water. And give him 100ml through G-Tube, pump or 4 syringes of 25ml each over 30 min period)
  • 3:30PM oral feed (soup made from a protein like fish, beef or chicken, with some vegetables and a carb like pasta, brow rice or potatoes …, he will usually eat around 30grams)
  • 4:30PM 5th formula mix feed (18g enfamil powder soy milk + 15.5g Cornstarch. mix with 100ml of water. And give him 100ml through G-Tube, pump or 4 syringes of 25ml each over 30 min period)
  • 6PM oral feed (soup made from a protein like fish, beef or chicken, with some vegetables and a carb like pasta, brow rice or potatoes …, he will usually eat around 30grams)
  • 7PM 6th formula mix feed (18g enfamil powder soy milk + 16.5g Cornstarch. mix with 100ml of water. And give him 100ml through G-Tube, pump or 4 syringes of 25ml each over 30 min period)
  • 8:30PM oral feed (soup made from a protein like fish, beef or chicken, with some vegetables and a carb like pasta, brow rice or potatoes …, he will usually eat around 15grams)
  • 9:30PM 7th formula mix feed (9g enfamil powder soy milk + 8g Cornstarch. mix with 50ml of water. And give him 25ml or 50ml depending on his sugar levels through G-Tube, pump or 1-2 syringes of 25ml each over 30 min period)
  • 11PM Glycosade (9g enfamil powder soy milk + 60g Glycosade. mix with 100ml of water. And give him all of it. around 150ml through G-Tube, pump or 4 syringes of ~40ml each over 30 min period)
As you can imagine, this is a very tedious schedule and you have to be on point, because if you start pushing one feed over by 15min for ex, then you have to shift the rest of the feeds for the rest of the day. We leverage a lot of tools and calculators which I’ve built in order to facilitate with the management of all of these related tasks. Everything is synced with our smartphones, from generating the feeding schedule every morning using google spreadsheets, to pushing it into a google calendar, and then setting up the right reminders and alarms for notifications; 

Sample Recipes

Progress Reports