Would you rather receive 50 euros today or wait a month to receive 100 euros? The answer says more about your health than you might imagine.
In a new study of almost 135,000 people, a team of researchers identified 11 genetic regions associated with the so-called temporal discount — the tendency to choose immediate rewards over bigger but future rewards.
The study concluded that people with a genetic predisposition to impatience showed associations with 212 medical conditionsalthough environmental factors play a much greater role than genes.
The genetic relationship is far from simple: impatience appears linked to ADHD, depression and smoking, but the opposite pattern is observed in disorders such as Obsessive-Compulsive Disorder, anorexia and schizophrenia, in which people, from a genetic point of view, tend to prefer to wait for greater rewards.
Scientists have discovered that the ability to delay gratification is, in part, inscribed in our DNA and that people who have more difficulty waiting are more likely to develop problems such as addictions, obesityheart disease, chronic pain and earlier health problems.
The , conducted by researchers from the University of California San Diego Researchers and the Californian company and published this Tuesday in Molecular Psychiatryidentified 11 specific sites in human DNA linked to this trait, known as temporal discounting (delay discounting).
The conclusions indicate that the impatience is not just a characteristic of personality or a matter of willpower. It is hereditary and has biological roots that are reflected in various dimensions of mental and physical health.
According to , researchers asked participants to answer a simple questionnaire, with 27 different choices. Someone who consistently chooses to smaller immediate rewards instead of bigger rewards in the future presents a more pronounced “discount”.
The team identified different genetic regions associated with this behavior, with clusters of genes in areas already known to influence the propensity to taking risks, intelligence, body weight and various psychiatric disorders.
As common genetic variants explain about 10% of the variation in the way people value immediate rewards over delayed rewards. Although environmental factors play a much more important role, this genetic component remains relatively stable throughout life.
Genes that shape the “now or later” decision
One of the main discoveries involves the chromosome 6where a genetic variant is located between two genes previously associated with the propensity to take risks, smoking, alcohol consumption, bipolar disorder and body mass index.
Another key point on chromosome 16 contains 18 genes that influence the brain development, intelligence and eating behaviorss. Changes in this region have been implicated in autism, ADHD, schizophrenia and obesity.
One of the identified genes, the SULT1A1produces a dopamine-induced enzyme in brain cells. Dopamine has been studied for decades in the context of reward and decision making, and this genetic link fits into this line of investigation.
Another gene, SH2B1helps regulate brain growth. Mice modified to lack this gene present brain development problems and aggressive behaviors.
The study shows that the genetic relationship with impatience is far from linear. A more pronounced temporal discount appears genetically linked to a greater risk of smoking, ADHD, depression and obesity.
But the pattern is reversed for Obsessive-Compulsive Disorderanorexia, autism, schizophrenia and bipolar disorder: people with a greater genetic predisposition to these conditions tend to prefer to wait for greater rewards. At both ends of the spectrum there are risks for health.
A intelligence and level of education were the factors that showed the strongest genetic overlap with temporal discounting.
But when researchers mathematically removed these effectsremained 19 associations, including links to smokingbody weight, brain connectivity patterns, digestive disorders and chronic pain.
In other words, some of the genetic factors linked to impatience are still present even after accounting for the role of intelligence and education.
Genetic risk predicts more than 200 medical conditions
To understand whether these findings translate into concrete effects on healthresearchers calculated time-discounted genetic risk scores for nearly 67,000 patients using clinical records from Vanderbilt University Medical Center.
The study found a link between a greater genetic risk of steeper discounting and 212 different medical diagnoses.
In addition to the expected links to tobacco use and mood disorders, this genetic risk was related to respiratory diseasessuch as chronic airway obstruction, heart disease, type 2 diabetesdigestive problems and chronic pain.
There were also age-related patterns. In young adults, a greater genetic load for temporal discounting was associated with more complications in pregnancy.
In middle-aged adultslinks to substance use disorders stood out, depression, diabetes and obesity. In older adults, cardiovascular associations predominated, including myocardial infarction and coronary disease.
Many of these associations have weakened When researchers took into account the smokingwhich suggests that cigarettes may explain part of the health consequences of impatience.
Even so, links to vision problems persistedskin diseases and some types of cancer, which indicates that there are multiple pathways linking impatience to health status.
Track impatience and impulsivity
People with more pronounced temporal discounting have relapse rates higher when trying to quit smoking. If impatience has identifiable biological roots, Future treatments may act on these mechanismsalthough this is far from being a clinical reality at the moment.
However, thousands of genetic variants contribute with very small effects. No single gene provides enough information to predict whether someone will have difficulty with impatience. Simple genetic tests will not be able to answer this question.
“Understanding the genetic and biological roots of temporal discounting opens up many new possibilities,” he says Sandra Sanchez-Roigesenior study author and associate professor of Psychiatry at UC San Diego School of Medicine, in a statement.
«In the future, temporal discounting could become a clinically useful markerwhich helps us improve behavioral and pharmacological treatments aimed at impulsivity», adds the researcher.
Different types of impulsive behavior have different biological bases. A person may be impatient with delayed rewards, but not necessarily be someone who acts without thinking or who likes to take physical risks.
Environmental factors play a huge role. Socioeconomic stress, trauma, substance use, and life experiences shape how people make decisions over time.
Growing up in poverty or living under chronic stress can, quite understandably, push someone towards a preference for immediate rewards.
Some of the associations between health and temporal discounting may rather reflect consequences of disadvantageous behavior than a direct biological link.
People who strongly devalue the future may smokeovereating, or avoiding preventative medical care — behaviors with immediate benefits but high long-term costs.
The temporal discount ends up link psychiatric and physical health in ways that traditional diagnoses do not capture, influencing health trajectories over decades and across seemingly disconnected medical domains, the study authors conclude.
