Scientists have discovered an immune system pathway in the brain that they think is the root cause of diseases related to obesity, Reuters reports. When mice were overfed, the hypothalamus secreted a compound that suppressed the conversion of food into energy, and led to inflammation associated with heart disease and diabetes. Altering the gene responsible through genetic engineering kept the mice slim and healthy.
A lead author of the study thought the actions of the hypothalamus were adaptations tailored to an earlier time in evolution, when food was scarce. Today, “this pathway is mobilized by a different environmental challenge—overnutrition.” Though genetic engineering in humans isn't an option, drugs or gene therapy might someday suppress the hypothalamus’ outdated activity. (Read more hypothalamus stories.)