Introduction: Omega-3 is one of the most essential fatty acids  that the body must receive from the diet. Many studies have shown that there is a relationship between consuming  diet containing omega-3 fatty acids (EPA, DHA) and maintaining brain function and reducing cognitive impairment. The present study aimed to determine the predictors of omega-3 supplements consumption in order to prevent the elderly Alzheimer based on the Health Belief Model (HBM) constructs.

Methods: This analytical cross-sectional study was conducted on 323 elderly referring to the health centers of Tehran city in 2016 selected using a random sampling method. The data collection tool included demographic information, knowledge, and the HBM constructs, distributed after confirming its validity and reliability. The results were analyzed by SPSS-18 software using statistical tests, including Chi-square, independent t-test, Pearson correlation coefficient, Spearman test, and logistic regression model.

Results: Logistic regression analysis showed that the best predictors of omega-3 supplements consumption were, respectively, knowledge, performance, self-efficacy, and perceived susceptibility that could predict 74.5% of consumption or not consumption of omega-3 supplementation. 

Conclusion: The present study led to identify the most powerful constructs of the HBM in predicting the behavior of omega-3 supplements consumption in the elderly. Therefore, this model can be designed and implemented as a reference framework to design educational interventions in preventing Alzheimer’s disease.