Low carbohydrate diets improve blood glucose control in patients with Maturity Onset Diabetes of the Young.

This study was published in the Journal of International Medical Research 2011;39(6):2296-301

Study title and authors:

The Influence of Dietary Carbohydrate Content on Glycaemia in Patients with Glucokinase Maturity-onset Diabetes of the Young.

Klupa T, Solecka I, Nowak N, Szopa M, Kiec-Wilk B, Skupien J, Trybul I, Matejko B, Mlynarski W, Malecki MT.

Department of Metabolic Diseases, Jagiellonian University Medical College, Krakow, Poland; Krakow University Hospital, Krakow, Poland.

This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/22289546

Maturity Onset Diabetes of the Young (MODY) is a group of diabetes disorders that affects about 2% of people with diabetes. MODY is often not recognised and people may be treated as Type 1 or Type 2 diabetes by their doctors. 

MODY has the following characteristics:

(i) Diabetes presents at a young age, usually less than 25 years of age.

(ii) MODY runs in families through several generations. A parent with MODY has a 50% chance of passing on MODY to their child. 

(iii) People with MODY do not produce enough insulin; this is different to Type 2 diabetes where people frequently produce lots of insulin but don't respond to their insulin.

There are six varieties of MODY:

MODY 1 Rare form of MODY. Similar effects to MODY 3.

MODY 2 Causes between 10-65% of MODY. Causes mild diabetes. Often diagnosed in childhood or pregnancy.

MODY 3 Causes between 20-75% of MODY. Causes progressive diabetes and patients may get diabetes complications. Usually diagnosed after puberty.

MODY 4 Rare form of MODY. Seems to produce relatively mild diabetes.

MODY 5 Rare form of MODY. Associated with kidney disease that is often diagnosed before diabetes.

MODY 6 Extremely rare form of MODY. Severity of diabetes unknown as yet. 

This study concerns MODY 2 which is a mutation in the glucokinase gene on chromosome 7. Glucokinase is an enzyme that acts as a glucose sensor so the beta cells in the pancreas produce the correct amount of insulin after a meal. However in MODY 2 the mutated glucokinase enzyme is less responsive to glucose entering the blood stream which results in continuously elevated high blood glucose levels.

This study evaluated the effect of the quantity of dietary carbohydrate on glucose levels in 10 glucokinase mutation carriers: seven with MODY and three with prediabetes. The patients were exposed to a 60% high-carbohydrate diet for two days and then switched to 25% low-carbohydrate diet for another 2 days.

The study found:

(a) On the high-carbohydrate diet, glucose levels were significantly higher compared with the low-carbohydrate diet.

(b) On the high-carbohydrate diet, spikes in glucose levels occurred significantly more frequently compared with the low-carbohydrate diet.

This study suggests that diets with a low carbohydrate content may improve blood glucose control in patients with Maturity Onset Diabetes of the Young.

Links to other studies:

The case for high fat/low carbohydrate diets in diabetes management

High fat/low carbohydrate diet decreases risk of heart disease

Diabetes patients health benefits from a high fat/low carbohydrate diet