Marion Feddersen Welkner
Principles and Practice of Clinical Research Program, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Facultad de Medicina, Clínica Alemana, Universidad del Desarrollo, Chile
Jorgelina Stegmann
Principles and Practice of Clinical Research Program, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Department of Research, Fundacion SPINE, Buenos Aires, Argentina
Miray Nilufer Cimsit Kemahli
Anatolia IVF and Women’s Health Center, Turkey
Diego Perez Paez
Principles and Practice of Clinical Research Program, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Clínica Dávila, Santiago, Chile
Hanna Bennewart
Principles and Practice of Clinical Research Program, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Dresden International University, Germany
Laura Amaral de Lara Resende
Principles and Practice of Clinical Research Program, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Virtu Oftalmologia, Belo Horizonte, Brazil
Fernando Espinoza
Hospital Central Militar, Mexico
Paula Aranguren
Principles and Practice of Clinical Research Program, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Beth Israel Deaconess Medical Center, Boston, MA, USA
Paula Bertagnoli
Principles and Practice of Clinical Research Program, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Faculdade São Leopoldo Mandic, Campinas, Brazil
Sarah Burgos
Principles and Practice of Clinical Research Program, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Two Oceans in Health, Santo Domingo, Dominican Republic
Nikolaos Paschos
Faculty of Dental Medicine, Medical University, Sofia, Bulgaria
Carlos Roa
Principles and Practice of Clinical Research Program, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Centro de Diagnóstico Medicina Avanzada y Telemedicina (CEDIMAT), Santo Domingo, Dominican Republic
Natália Puschnick Gimenez
Principles and Practice of Clinical Research Program, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Faculdade São Leopoldo Mandic, Campinas, Brazil
Letícia Cabreira dos Santos
Principles and Practice of Clinical Research Program, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Faculdade São Leopoldo Mandic, Campinas, Brazil
Lissa Raquel Sandoval Castillo
Principles and Practice of Clinical Research Program, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Universidad Francisco Marroquín, Guatemala City, Guatemala
Karla Andrade Ruiz
Principles and Practice of Clinical Research Program, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Universidad San Francisco de Quito, Hospital Metropolitano de Quito, Ecuador
Siddiha Poovelil Shahulhameed
Principles and Practice of Clinical Research Program, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Hamad Medical Corporation, Doha, Qatar
Paulina Troncoso Escudero
Principles and Practice of Clinical Research Program, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Laboratorio de Diagnóstico Molecular y Biomarcadores, Facultad de Medicina, Clínica Alemana, Universidad del Desarrollo, Chile
Priscila Sales Barroso
Principles and Practice of Clinical Research Program, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Eli Lilly do Brasil, São Paulo, Brazil
Yulissa Hernández Frías
Principles and Practice of Clinical Research Program, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Centro de Diagnóstico Medicina Avanzada y Telemedicina (CEDIMAT), Santo Domingo, Dominican Republic
Daniela Vicinansa Monaco Ferreira
Principles and Practice of Clinical Research Program, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Faculdade São Leopoldo Mandic, Instituto de Pesquisa São Leopoldo Mandic, Campinas, Brazil
Ala Hassan
Principles and Practice of Clinical Research Program, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Hamad Medical Corporation, Doha, Qatar
Henrique Balseiro Zin
Principles and Practice of Clinical Research Program, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Faculdade de Medicina da Universidade de São Paulo, Brazil
Alice Campanholo de Oliveira
Principles and Practice of Clinical Research Program, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Faculdade São Leopoldo Mandic, Campinas, Brazil
Jae Kyung Jo
Principles and Practice of Clinical Research Program, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Blue Hill Medical Foundation, Suwon, Republic of Korea
Fernando Jose Gomez Juarez
Principles and Practice of Clinical Research Program, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Universidad Francisco Marroquín, Guatemala City, Guatemala
Roy Rosado
Principles and Practice of Clinical Research Program, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Universidad Francisco Marroquín, Guatemala City, Guatemala
Abstract
Background: Depression is a leading global cause of disability, and identifying modifiable lifestyle factors such as caffeine intake may help mitigate its burden. Although caffeine consumption has been proposed as protective against depressive symptoms, existing evidence remains inconsistent and often insufficiently adjusted for key confounders.
Objective: To examine the association between caffeine intake and depressive symptoms among U.S. adults using data from the 2017–2018 National Health and Nutrition Examination Survey (NHANES).
Methods: This cross-sectional study was conducted and reported according to STROBE guidelines. Adult NHANES participants were included. Daily caffeine intake (mg/day), assessed via 24-hour dietary recall, was categorized as low, moderate, or high. Depressive symptoms were measured using the Patient Health Questionnaire-9 (PHQ-9) and classified into five clinically meaningful severity levels. Weighted ordered logistic regression models were used to evaluate associations between caffeine intake and depressive symptom severity, adjusting for demographic, socioeconomic, lifestyle, and clinical covariates, including age, sex, education, body mass index (BMI), marital status, family income, ethnicity, smoking status, sedentary behavior, thyroid disease, diabetes, and cardiovascular disease.
Results: The analytic sample included 4,503 adults (mean age 47.3 years; 51.8% female). Caffeine intake was low in 47%, moderate in 27%, and high in 26% of participants. In weighted univariable analyses, both moderate (OR 0.73; 95% CI 0.60–0.90; p=0.006) and were associated with lower odds of more severe depressive symptoms compared with low intake. After multivariable adjustment, only high caffeine intake remained independently associated with lower depressive symptom severity (OR 0.62; 95% CI 0.48–0.80; p=0.001). In adjusted models, female sex, obesity, unmarried status, current smoking, thyroid disease, and cardiovascular disease were independently associated with higher odds of depressive symptoms, whereas higher educational attainment and higher family income were independently associated with lower odds of depressive symptoms.
Conclusions: High caffeine intake was independently associated with lower depressive symptom severity in U.S. adults, even after accounting for a broad range of confounders. However, several demographic, socioeconomic, and health-related factors exerted stronger and opposing influences on depressive symptoms. These findings suggest that while caffeine consumption may play a modest protective role, addressing broader social and health determinants is likely more impactful for depression prevention and management. Longitudinal studies are needed to clarify causality and temporal relationships.
