Vitamins and Their Essential Functions

Study Notes

Introduction

Vitamins are essential nutrients required by the body to carry out various normal functions. They play a crucial role in maintaining health and can prevent deficiency diseases. Unlike macronutrients like carbohydrates, proteins, and fats, vitamins are needed in smaller quantities. There are two classes of vitamins: fat-soluble and water-soluble. Fat-soluble vitamins include A, D, E, and K, while water-soluble vitamins consist of C and the B vitamins (thiamine, riboflavin, niacin, pantothenic acid, biotin, and choline). Each vitamin plays a distinct role in the body, and deficiencies can lead to specific health issues.

Essential Roles of Vitamins

Fat-Soluble Vitamins

Vitamin A

Function: Essential for eye health and prevents night blindness.

Vitamin D

Function: Promotes calcium absorption for bone growth and helps regulate immune response.

Vitamin E

Function: Acts as an antioxidant, protecting cells from damage caused by free radicals.

Vitamin K

Function: Necessary for blood clotting and maintains healthy bones.

Water-Soluble Vitamins

Vitamin B1 (Thiamine)

Function: Supports energy production and nerve function.

Vitamin B2 (Riboflavin)

Function: Helps convert food into energy and supports cellular processes.

Vitamin B3 (Niacin)

Function: Plays a key role in DNA repair and energy metabolism.

Vitamin B5 (Pantothenic Acid)

Function: Involved in synthesizing cofactors used in energy production and fatty acid formation.

Vitamin B6 (Pyridoxal phosphate)

Function: Synthesizes neurotransmitters, hemoglobin, and supports metabolic reactions.

Vitamin B7 (Biotin)

Function: Assists enzymes involved in energy production, cell signaling, and protein synthesis.

Vitamin B9 (Folate)

Function: Important for DNA synthesis and growth.

Vitamin B12

Function: Necessary for proper nerve function and brain development, and supports DNA synthesis.

Vitamin C (Ascorbic Acid)

Function: Acts as an antioxidant, helps with collagen production and wound healing.

Dietary Sources of Vitamins

Essential vitamins can be obtained through a balanced diet rich in fruits, vegetables, whole grains, lean proteins, and dairy products. Each food source contains different combinations of vitamins, so it's important to consume a wide variety to ensure adequate intake.

Recommendations for Vitamin Intake

The National Academies of Engineering and Medicine have established Dietary Reference Intakes (DRIs) for various vitamins based on age, gender, and other factors. These values are recommended daily levels of intake to meet the nutrient needs of nearly all healthy individuals.

Description

Learn about the different classes of vitamins, their essential roles in the body, dietary sources, and recommended intake levels. Understand how vitamins like A, D, E, K, and various B vitamins play crucial roles in maintaining health and preventing deficiencies.