In our climate-changing world, one threat is rising temperatures and concerns about heat waves. If that statement is not strong enough, researchers at the University of California Irvine have found evidence of the damage heat stress causes to the body at the molecular level—damage to the gut, liver and brain especially in the elderly. The study, in the journal Scientific Reports, used laboratory animals to demonstrate a communication system in the body that touches everything from the gastrointestinal tract to the nervous system. Authors say by investigating the effects of heat stress on communications between the brain, gut and liver they hope to better protect our increasingly vulnerable aging population from the encroaching intense heat waves.