Discuss why nutrition is a central component in health promotion. What are some of the nutritional challenges for emerging populations? What roles do nutritional deficiency and nutritional excess play in disease?  (Using 200-300 words APA format with at least two references. Sources must be published within the last 5 years. There should be a mix between research and your reflections. Add critical thinking in the posts along with research. Apply the material in a substantial way.) Note: Please do not use material from Course Hero as my instructor checks it. Original material needed please.