Drinking High Carbohydrate Shakes Can Hamper Heart Function

01 Apr 2016 --- Scientists have found that drinking a high carbohydrate shake can have an acute and detrimental effect on heart function.

After drinking a high-carbohydrate shake many things can happen, including increases in glucose and insulin.

Researchers studied 33 individuals who were given an acute carbohydrate load in the form of a “high-carb” shake.

They studied their blood levels for six hours looking for things like whether this acute metabolic challenge could alter the heart's production of atrial natriuretic peptide (ANP).

ANP is a hormone that helps the body get rid of excess salt and reduces blood pressure.

Before the participants began the study, they were normalized on a standard diet for a couple of days to remove any background dietary variability.

The findings, published in the Journal of the American College of Cardiology (JACC), showed that drinking the high-carb shake led to a 25 percent reduction in ANP in participants over the course of several hours.

If a high dietary carbohydrate load suppresses circulating ANP concentrations, this would be a disadvantage to obese individuals who have lower ANP levels to begin with.

"The carbohydrate load had a significant and notable effect on circulating ANP levels. Experimental studies suggest that it's not good to make less ANP and ‘Carb loading’ may not be ideal for the body," said senior author Thomas Wang from Vanderbilt University Medical Center in the US.

“When you take in a high-carb shake a lot of things happen, including increases in glucose and insulin,” he added. "However, the increase in glucose appears to be the main thing driving the drop in ANP levels," Wang explained.

UAB's Pankaj Arora, M.D., first author of the JACC study, helped to work out the novel chemical pathways that mediated the effect of glucose on heart cells.

This novel mechanism involved a molecule known as miR-425, which the research group has previously described as an inhibitor of ANP production. The glucose causes the cells to make more miR-425, and that, in turn, causes a reduction in ANP.