Cooperative and caring behaviors are key drivers of human social progress, especially during catastrophes or pandemic events. While COVID-19 pandemics was arriving to Colombia in absence of any approved therapeutic strategy or vaccine, and based on evidence from other viral diseases, we anticipated to hypothesize the protective role of some nutritional supplements such as Vitamin D and C against SARS-CoV2. Therefore, for health workers, we proposed a voluntarily nutritional supplementation plan to fortify their immune system aiming to prevent or mitigate eventual COVID-19 infection and disease. Using the behavioral EAST framework, all our health workers (n = 1,063) were invited via email to participate voluntarily in a supplementation strategy for a period of 3 months. 77.4% accepted participation, and among them, we identified a group with optimal adherence to the proposed supplementation plan (20%) and a predominant group with no adherence at all (57.29%). Adherence seemed to be associated to a risk perception bias that was predominant in female workers and those workers performing in working areas with higher risk of infection. Of importance, adherence to the supplementation strategy was associated to a lower percentage of COVID-19 diagnostics (12%) as compared with that observed in non-adherence participants (19%). Moreover, the sustained adherence during the time of intervention seemed to promote adoption of this target behavior, as up to 35% of the adherent participants remained attached (on their own) to the supplementation habit, 3 months after the end of the intervention. All these data show the potential relevance of EAST frameworks as tools to trigger health care and altruistic behaviors to avoid the spread of pandemic diseases. In line with other authors, our observations suggest that nutritional vitamin D and C supplementation could mitigate the risk of COVID-19, highlighting the behavioral and biological relevance of this type of interventions during emerging or re-emerging infectious diseases.