**5. Conclusions**

Our findings shown that practicing acts of kindness decreased materialism and external aspirations aimed at financial success. However, we observed the same effect in the control condition. Although our study is not conclusive as to whether practicing kindness leads to a decrease in materialism, it does indicate that kind women are less oriented toward external materialistic aspirations and more toward internal aspirations, especially those related to maintaining good relationships with other people, and are less willing to buy impulsively. Overall, kindness interventions are a promising tool for practitioners to reduce materialism and therefore have the potential to improve public health. We believe that our pioneering research will initiate further research to examine the impact of practicing kindness on materialism and consumption behavior.

**Supplementary Materials:** The following supporting information can be downloaded at: https: //www.mdpi.com/article/10.3390/ijerph192316339/s1.

**Author Contributions:** Conceptualization, D.D. and R.T.; methodology, D.D. and R.T.; formal analysis, D.D. and R.T.; investigation, R.T.; resources, D.D. and R.T.; data curation, R.T.; writing—original draft preparation, D.D.; writing—review and editing, D.D. and R.T.; project administration, R.T.; funding acquisition, D.D. All authors have read and agreed to the published version of the manuscript.

**Funding:** The study was funded by the Faculty of Psychology and Cognitive Science, Adam Mickiewicz University in Pozna ´n.

**Institutional Review Board Statement:** The study was conducted in accordance with the ethical standards of the Institutional Research Committee (Ethical Committee of Faculty of Psychology and Cognitive Science, Adam Mickiewicz University in Pozna ´n) and with the rules of the Helsinki Declaration of 1975, as revised in 2013. The Institutional Research Committee in 2019, when the study was conducted, did not require submission of the study procedure for approval if the study did not raise ethical concerns.

**Informed Consent Statement:** Informed consent was obtained from all subjects involved in the study.

**Data Availability Statement:** The dataset is available for free download from the Open Science Framework (https://osf.io/bc67z/?view\_only=bf4933a3537c4fb3be29baec43a5b761, accessed on 6 October 2020).

**Conflicts of Interest:** The authors declare no conflict of interest.
