Among 5,152 U.S. adults tracked from 2021–2023 in the CHASING COVID Cohort, being sedentary combined with moderate-risk alcohol use produced the sharpest elevation in anxiety and depression risk. In a healthier subsample (n=3,141, excluding chronic conditions), sedentary moderate-risk drinkers showed a nearly doubled risk of moderate-to-severe anxiety/depression symptoms compared to active low-risk drinkers (aRR=1.92, 95% CI: 1.50–2.45). Physical activity statistically modified this relationship on both additive (RERI=0.61) and multiplicative scales among healthier participants, though not in the full cohort.
This preprint, not yet peer-reviewed, adds meaningful texture to a long-debated question: can exercise buffer the mental health harms of alcohol? The answer here is nuanced — physical activity appears protective primarily among otherwise healthy adults, suggesting that underlying health status conditions the interplay between these behaviors. The finding aligns with prior observational work showing exercise attenuates stress-axis dysregulation and inflammation, both implicated in alcohol-related mood disorders. Crucially, the effect modification disappears in the full sample, implying sick-quitter bias — where ill individuals who reduced drinking appear as low-risk drinkers — can obscure true associations. Limitations include observational design precluding causality, self-reported activity and alcohol measures, and a COVID-era cohort that may not generalize broadly. Still, for clinicians and adults managing mental health, these findings reinforce that regular physical activity may partially offset depression risk linked to moderate drinking — an incremental but practically meaningful insight.
