The number of sports venue operators (top) and total wagers in the U.S. (bottom) surged from 2017 to 2023. (Image courtesy of John W. Ayers of UC San Diego.)
Unprecedented Growth in Sports Betting
Since the 2018 Supreme Court ruling, the study documents staggering growth in the sportsbook industry:
- The number of states with operational sportsbooks grew from 1 in 2017 to 38 in 2024.
- Total sports wagers skyrocketed from $4.9 billion in 2017 to $121.1 billion in 2023, with 94% of wagers during 2023 placed online.
“Sports betting has become deeply embedded in our culture,” said Matthew Allen, a third-year medical student. “From relentless advertising to social media feeds and in-game commentary, sportsbooks are now everywhere. What was once a taboo activity, confined to the fringes of society, has been completely normalized.”
The researchers note these trends are projected to grow, in no small part due to the industry’s investment in sportsbooks as the future of gambling, as evidenced by Caesars Entertainment’s rebranding to Caesars Sportsbook and Casino.
A Public Health Blind Spot
“Despite gambling addiction as a recognized disorder in the Diagnostic and Statistical Manual of Mental Disorders, it remains largely overlooked in healthcare and public health with no formal ongoing surveillance,” said Kevin Yang, M.D., a third-year resident physician in the Department of Psychiatry. “Without systematic surveillance, we are flying blind while millions bet on sports.”
To fill this gap, the research team analyzed aggregate Google search trends for queries that mentioned gambling, addiction, addict, anonymous or hotline, from January 1, 2016, through June 30, 2024.
“Many people struggling with addiction don’t openly discuss it, but they do turn to the internet for answers,” said Davey Smith, M.D., professor of medicine and director of ACTRI. “By analyzing search trends, we can gain real-time insight into the true scale of gambling addiction in the U.S.”
Record Levels of Gambling Addiction Help Seeking
Parallel with the growth in sportsbooks, internet searches for help with gambling addiction, such as “am I addicted to gambling”, have cumulatively increased 23% nationally since Murphy v. NCAA through June 2024. This corresponds with approximately 6.5 to 7.3 million searches for gambling addiction help-seeking nationally, with 180,000 monthly searches at its peak.
By state, the opening of sportsbooks consistently corresponded with increased demand for gambling addiction help seeking. Illinois (35%), Massachusetts (47%), Michigan (37%), New Jersey (34%), New York (37%), Ohio (67%), Pennsylvania (50%) and Virginia (30%) all experienced significant increases in gambling addiction-related searches following the opening of any sportsbooks in their state.
“The significantly higher search volumes observed in all eight states make it virtually impossible that our findings occurred by chance,” said Atharva Yeola, a student researcher in the UC San Diego Qualcomm Institute. “Statistically speaking, the probability of these results happening randomly is less than one in 25.6 billion.”
Online Sportsbooks Drive Even Greater Risk
The study found that online sportsbooks had a substantially greater impact on gambling addiction help-seeking than traditional brick-and-mortar sportsbooks. For example, in Pennsylvania:
- The introduction of retail sportsbooks led to a 33% increase in gambling addiction help seeking searches during the five months before online sportsbooks launched.
- When online sportsbooks became available, searches surged 61%—a significantly greater and more sustained increase that persisted for years