Glycemic Index And Brain Function

The Study

In this interesting study, 25 type 2 diabetics consumed a high or low glycemic breakfast, lunch and dinner on 2 separate occasions. The glycemic index is a measure of how a carbohydrate food impacts your blood sugar. High glycemic foods cause a spike in glucose and insulin levels and low glycemic foods have a more modest impact on blood sugar and insulin. All subjects went through a battery of cognitive tests during each study day.

The subjects had a significant improvement in global cognitive and executive functioning when comparing the low glycemic day to the high glycemic day.

American Journal of Clinical Nutrition 2023; 117:859-69.
 
Take Home Message

It sounds funny saying this, but the way you eat can impact how smart you are. Your brain works better when you eat in a way that provides a stable blood sugar.

The authors proposed several potential mechanisms for the cognitive benefits seen in this study after the low-glycemic index meal plan:

-More energy on the low GI day was responsible for the improvements in cognitive function.

-A better mood on the low GI day was responsible for the improvements in cognitive function.

-Less hunger on the low GI day was responsible for the improvements in cognitive function.

-Improvements in cerebral blood flow may also be responsible.

When it comes to carbs, focus on fruits, vegetables, legumes and whole grains such as oatmeal, quinoa and brown rice. Strictly limit bread, pasta, white rice and sugar.