Vitamins were first discovered in 1921
- Casamir Runk coined the term vitamin
	- Vita = life
	- Amine = a type of nitrogen containing substance
	- The first discovered vitamin was thiamin
- There are 13 known vitamins, plus 5 vitamin like substances
- It is unlikely that any new vitamins will be discovered - (babies and sick people can live on synthetic liquid diet?)
- A vitamin is a complex organic compound that regulates certain metabolic processes
	- Cannot be synthesized in sufficient quantities by the body
	- Occurs naturally in foods
	- Deficiency disorder occurs if substance is missing from the body
	- They do not provide any energy
- Vitamins are organic, but they differ from macronutrients:
	- **Not metabolized for energy**
	- Present in small amounts in foods
	- Required in milligram and microgram amounts
- Because vitamins are organic
	- They are subject to heat degradation
	- Exposure to excessive heat, alkaline substances, light, and air can destroy certain vitamins
	- **Water soluble vitamins can leach out of food and dissolve in cooking water**
# Fat Soluble Vitamins
- Fat soluble vitamins are **K, A, D, E**
	- Found in lipid portions of the body
	- Associate with lipids in the body
	- **Digested and absorbed with fats
	- Stored in the body
	- Can cause toxicity

| Nutrient            | Function                                                                                                                                 | Deficiency                                                                                                                                                      | Toxicity                                                                                                            | Sources                                                                                                       | Other Info                                                                         |
| ------------------- | ---------------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------- |
| Vitamin A (Retinol) | - Vision (Retina + Cornea)<br>- Growth and Reproduction<br>- Immune Function<br>- Epithelial (Skin)<br>- Cells<br>- Bone<br>- Remodeling | - Night Blindness (Nycatlopia)<br>- Xerophthalmia<br>- Dry Eyes -> Blindness<br>- Poor Growth<br>- Dry Skin or Tissue<br>- ^ Causes increased risk of infection | - Carotenemia (Orange colored skin)<br>- Birth defects<br>- Bone fractures<br>- Liver damage<br>- Nausea / Vomiting | Vegetables:<br>- Yellow, orange, or dark green (pumpkin, squash, carrots, spinach)<br>Milk and Dairy Products | - Retinol's precursor is beta-carotene (antioxidant)<br>- Helps with wound healing |
|                     | -                                                                                                                                        |                                                                                                                                                                 |                                                                                                                     |                                                                                                               |                                                                                    |
# Water soluble vitamins
- Water soluble vitamins are the **B-vitamins**: thiamin, riboflavin, niacin, vitamin B-6, pantothenic acid, folate, biotin, vitamin B-12, and **vitamin C**.
	- They dissolve in water
	- **Very limited amounts are stored** with the exception of B-12
	- **Kidneys will filter out excess water soluble vitamins**
	- Less likely to be toxic

# Oxidization
- An *oxidizing agent* is a substance that removes electrons from atoms or molecules
- A *free radical* is a substance (C, H, O) with an unpaired electron
	- Highly reactive, damages and destroys molecules
- **Antioxidants (Vitamin E, C)** are substances that **give up electrons to free radicals to protect cells**

# Vitamin Intake
**Bioavailability** is the amount of a vitamin available for use in the body
- Factors that affect how available a vitamin is include:
	- How long it takes the vitamin to pass through the intestinal tract
	- Certain health conditions that affect the absorption of facts
	- By cooking with a little bit of fat, you better absorb fat soluble vitamins from that meal.
- Natural sources of vitamins typically provide higher availability
It's important to preserve the vitamin content of food, ways to do so include:
- Avoid decaying, wilting, or bruised fruits or vegetables
- Fresh produce should refrigerated at high humidity, away from the open air
- Exposure to excessive heat, alkaline (salty) substances, light, and air can all reduce the vitamin content of food
- **Vegetables should be cooked in small amounts of water, using quick cook methods**