Globalization is the process of increasing interconnections and linkages, within societies and across geography, due to improved communication and expanded world trade. It limits the differentiation wrought by human cultural evolution, and homogenizes health practices, diet and lifestyle. There are both beneficial and adverse consequences of the globalization process. Globalization also presents a challenge to the development of ethics for practice and advocacy by food and nutrition professionals. Among the related terms, ‘morals’, ‘values’ and ‘ethics’, the latter connotes the basic rules of conduct for interactions within society and with the inanimate environment; rules based on recognized principles (ethical principles). The application of these principles is to resolve ethical dilemmas that arise when more than one interest is at play. Recognized ethical principles include autonomy, beneficence, non-maleficence, justice, utility and stewardship. These can be framed in the context of issues that arise during advocacy for material and behavioural changes to improve the nutritional health of populations. Clearly, at the global level, codes of good conduct and the construction of good food governance can be useful in institutionalizing ethical principles in matters of human diets and eating practices. Ethical dilemmas arise in the context of innate diversity among populations (some individuals benefit, whereas others suffer from the same exposures), and due to the polarity of human physiology and metabolism (practices that prevent some diseases will provoke other maladies). Moreover, the autonomy of one individual to exercise independent will in addressing personal health or treatment of the environment may compromise the health of the individual's neighbours. The challenges for the professional in pursuit of ethical advocacy in a globalized era are to learn the fundamentals of ethical principles; to bear in mind a respect for difference and differentiation that continues to exist, and which should exist, among individuals and societies; and to avoid a total homogenization of agriculture and food supplies.