An Amhersts environmental health scientist has developed an “overlooked hypothesis” to help explain the global population decline expected to begin in 2064: social stress. The article was published in the journal Endocrinology. Stress from social media and other empty or overwhelming social interactions may lead or contribute to changes in reproductive behavior and reproductive physiology, says Alexander Suvorov, associate professor at UMass Amherst School of Public Health and Health Sciences. Through research, he examines various theories surrounding past population declines as models predict a “remarkable” decline from 9.7 billion people in 2064 to 8.8 billion End of the century. “A unique feature of the coming population decline is that it will be caused almost exclusively by reduced fertility, rather than by factors that increase mortality (war, epidemics, starvation, weather conditions). extreme weather, predators and catastrophic events),” he wrote. Suvorov outlines a hypothesis connecting reproductive trends with population density, proposing that density reflects the quality and frequency of social interactions. “Increasing population numbers contribute to less meaningful social interactions, social withdrawal, and chronic stress, followed by reproductive suppression,” the manuscript states. Over the past 50 years, a 50% decrease in sperm count has occurred. Stress is known to inhibit sperm count, ovulation and sexual activity, notes Suvorov. Although changes in reproductive physiology are often attributed to the effects of endocrine-disrupting pollutants, Suvorov believes it is not the only factor. “Numerous laboratory and wildlife studies have demonstrated that population peaks are always followed by stress and reproductive suppression,” Suvorov said. “When high population densities are achieved, something is happening in the nervous system that is preventing reproduction. The same mechanisms that occur in wild animals may also be at work in humans. ” Suvorov points to several changes in reproductive behavior that contribute to population decline, including people having fewer children and waiting longer to start families or choosing not to have children. But he says biological changes can also occur. More research is needed, he said, such as studies to determine cortisol levels in people’s blood, an important measure of stress. “A better understanding of the causal chain involved in reproductive suppression by factors related to population density may help develop interventions to treat infertility and other reproductive conditions “, Suvorov wrote. He hopes his hypothesis offers an exciting area of research that scientists from different fields will be interested in exploring. “The goal of this article is to draw attention to a completely overlooked hypothesis – and which is raising more questions than giving answers,” Suvorov said. “I hope it will trigger the interest of people from very different fields and that after additional research we will have a much better picture of how population density is connected to stress.” society and how social stress is connected to reproduction and what we can do about it.” A common place to start, he suggests: “Back off social media.”
