New Link Between Obesity and Insulin Resistance Uncovered

The high BCAA protein levels found in obese individuals, combined with high fat diets, could significantly increase the incidence of pre-diabetic insulin resistance. Because obesity and diabetes are so closely linked, this finding could go a long way in explaining the cause and effect of the obesity-diabetes connection, as well as lay the foundations for future preventative treatments for diabetes in obese individuals.

Branched-chain amino acids (BCAAs) are a common dietary protein, found most prominantly in meat. BCAAs have also been found in past research to be in high abundance in obese individuals. While this observation itself has not been proven to significantly impact the development of dangerous conditions related to obesity, such as diabetes and heart disease, the potential has been there that BCAA mechanisms may contribute to the development of these conditions.

Specifically, it was found by the current researchers that high levels of BCAAs in obese individuals effect the “metabolic processing” of the amino acids, which could be the connection that leads to insulin resistance. Says senior author Dr. Christopher Newgard, “In the case of the amino acids, we also are finding increased levels of their metabolic breakdown products, which suggests the whole system for handling the amino acid metabolic process has been overloaded.”

This “overload” was shown to be directly linked to insulin resistance in obese mice being fed high fat diets, in the current study. “Insulin resistance occurred in animals with a diet high in the branched-chain amino acids, but only if they were ingested along with a high level of fat in the diet,” says Dr. Newgard.

Since obese people very often ingest diets high in fat, if the above findings are confirmed in future human studies, a potential chemical explanation for why insulin resistance is so common in obese individuals, could result.

Source: Defeat Diabetes Foundation: Newgard, Christopher. Jane Gore, Mary. Duke University Medical Center news release. April 2009.