SUMMARY
Achieving equity in health is an ethical challenge worldwide. Although it is known that health depends on diverse factors, bioethics has been focused on equity in health care.The knowledge of the macro-determinants of health and their effects in the practices and analysis, as well as the principles of autonomy and justice, legitimize equity in health as a substantive area of bioethics. Some relevant issues are: relation between macro-determinants of health and lifestyles; social distribution of freedom of choice; ethical tensions in health promotion policies; justice in health care; ethical appreciation of construction of indicators and their evaluation; definition of "health" and "equity in health". The analysis of equity in health opens new fields of reflection and practice towards a bioethics centered in population health.