Researchers from Canada compared the effects of a low-glycemic index (GI) diet vs a high-cereal fiber diet in patients with type 2 diabetes.

GI is a measure of the effects of carbohydrates on blood sugar levels.

• Carbohydrates with a high GI are digested rapidly and release glucose rapidly into the blood.
• Carbohydrates with a low GI are digested slowly and release glucose gradually into the blood.
• Comparisons are made to white bread (GI of 100): glucose at 138, brown rice at 81, and fructose at 31.

First, the details.

• 210 participants being treated for type 2 diabetes were randomly assigned to receive 1 of 2 diet for 6 months.
  • High-cereal fiber
  • Low-GI dietary advice
• At the start of the study, participants had an A1c of 7.1% (the goal is less than 7% for this marker of long-term diabetes control).
• The average body mass index (BMI) was about 31 (overweight).

And, the results.

• A1c decreased significantly with the low-GI diet vs the high-cereal fiber diet.
• HDL (good) cholesterol increased significantly with the low-GI diet compared to a decrease with the high-cereal fiber diet.
• Reducing the dietary GI was associated with a significant reduction in A1c and an increase in HDL cholesterol.

The bottom line?
The authors concluded, “In patients with type 2 diabetes, 6-month treatment with a low-GI diet resulted in moderately lower A1c levels compared with a high-cereal fiber diet.”