Chapter 8 – Vitamins

8.1 Introduction to Vitamins

Malia paha he iki ‘unu, pa‘a ka pōhaku nui ‘a‘ole e ka‘a.

Perhaps it is the small stone that can keep the big rock from rolling down.

Vitamins and the Case of the Karat Banana

Vitamins are essential nutrients that our bodies require in small amounts to maintain good health. They come from the foods we eat, so when a diet lacks certain types of food, vitamin deficiencies can occur.

A striking example comes from Pohnpei, a Pacific island in the Federated States of Micronesia. For generations, people there have eaten traditional foods such as fresh papaya, mango, pineapple, coconut, bananas, and seafood. In recent years, however, many residents have shifted toward imported, processed foods that are low in vitamins and minerals.

Karat Banana look similar to a mango
Figure 8.1.  Karat bananas look very similar to mangos with an orange flesh, which is high in vitamin A. (Image by University of Hawaii at Mānoa licensed CC BY-NC-SA.)

This change has led to serious health problems. In one study of children aged two to five, more than half were deficient in vitamin A.[1]

To address this issue, the Island Food Community of Pohnpei began promoting the bright-orange karat banana, a traditional variety rich in beta-carotene, which the body can convert into vitamin A. Encouraging families to return to this local, nutrient-dense food has helped reduce vitamin A deficiency and preserve cultural food traditions.

Watch: Island Food Community of Pohnpei – Karat Banana Story

Learn more: islandfood.org

Chapter 8 Learning Objectives

By the end of this chapter, you will be able to:

  • Define vitamins and explain how they differ from macronutrients in supporting health.
  • Compare fat-soluble and water-soluble vitamins and describe how they are absorbed, stored, and excreted.
  • Identify the major functions, food sources, and health benefits of vitamins.
  • Describe the consequences of vitamin deficiencies and toxicities, including populations at greater risk.
  • Evaluate Dietary Reference Intakes (DRIs), food sources, and supplements as ways to meet vitamin needs.


  1. Yamamura CM, Sullivan KM. Risk factors for vitamin A deficiency among preschool-aged children in Pohnpei, Federated States of Micronesia. J Trop Pediatr. 2004;50(1):16-19. https://www.ncbi.nlm.nih.gov/pubmed/14984164 ↵

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