Tabriz University of Medical Sciences Journal of Cardiovascular and Thoracic Research 2008-5117 18 1 2026 03 30 Beyond calories: the effect of meal patterns on obesity risk in the IRanian National Obesity Registry 26 31 10.34172/jcvtr.026.33600 EN Mina Nosrati https://orcid.org/0000-0002-6300-8806 Niosha Samadi Ali Mottaghi Moghadam Shahri Mahsa Tousi Farnaz Farrokhzadeh Fateme Kourepaz Najmeh Seifi Khalil Kimiafar https://orcid.org/0000-0003-0351-4675 Majid Ghayour Mobarhan https://orcid.org/0000-0002-1081-6754 Journal Article 10.34172/jcvtr.026.33600 2025 05 22 2025 10 11 Introduction: The prevalence of obesity is increasing. Eating habits are modifiable factors that may be effective in reducing obesity. We aimed to investigate the relationship between meal frequency and daily breakfast and the presence of obesity. Methods: A total of 4137 overweight and obese individuals registered on IRanian National Obesity Registry (IRNOR) in 2022 were recruited into this cross-sectional study. Individual data was recorded using a self-reported questionnaire. Multivariate logistic and linear regressions were used to evaluate the association between meal frequency, daily breakfast and obesity. Results: There was a lower significant odd of obesity (odd ratio (OR)=0.80, 95% confidence interval (CI): 0.69-0.93; P=0.004) in people who reported having more than three meals a day. There was a lower odd of obesity (OR=0.79, 95%CI: 0.69-0.91; P=0.001) in individuals who had daily breakfast and higher odds of obesity (OR=1.21, 95%CI: 1.03-1.42; P<0.01) for individuals who reported dinner as their main meal of the day. There was a significant association between eating frequency and daily breakfast with central obesity in men and in women; there was a significant inverse relationship between eating breakfast and central obesity. Conclusion: Meal frequency and eating breakfast daily as a modifiable eating habits can lead to improvement obesity.