Vitamin B3 (Niacin)

Vitamin B3, also known as niacin, is a water-soluble vitamin that is essential for the body's metabolism. It plays a crucial role in converting food into energy and is important for maintaining the health of the skin, nervous system, and digestive system.

Functions of Vitamin B3

• Energy Production: Vitamin B3 is a key component of coenzymes involved in the production of energy from carbohydrates, fats, and proteins.
• Cellular Metabolism: It is involved in over 200 enzymatic reactions in the body, contributing to the proper function of cells and tissues.
• Cholesterol Regulation: Niacin has been shown to help lower LDL cholesterol and triglycerides while increasing HDL cholesterol levels, thereby supporting cardiovascular health.
• Skin Health: Niacin is essential for maintaining healthy skin and is often included in skincare products for its beneficial effects.

Sources of Vitamin B3

Vitamin B3 can be obtained from a variety of food sources, including:

• Meat (beef, pork, turkey, chicken)
• Fish (tuna, salmon)
• Nuts and seeds
• Legumes (peas, lentils)
• Whole grains
• Fortified cereals
• Mushrooms
• Green vegetables (avocado, asparagus)

Deficiency and Toxicity

A deficiency of vitamin B3 can lead to a condition known as pellagra, characterized by symptoms such as dermatitis, diarrhea, and dementia. However, vitamin B3 toxicity is rare and usually occurs only with high-dose supplementation, leading to symptoms such as flushing, itching, and liver toxicity.

Recommended Intake

The recommended dietary allowance (RDA) for niacin varies by age and gender. As of 2021, the RDA for niacin for individuals aged 14-18 is 16 mg per day for males and 14 mg per day for females.

Study Guide

Here are some key points to remember about vitamin B3 (niacin) for your study guide:

1. Function of vitamin B3 in energy production and cellular metabolism
2. Sources of vitamin B3 in food
3. Effects of vitamin B3 deficiency and toxicity
4. Recommended dietary allowance (RDA) for niacin

Understanding the importance of vitamin B3 and its role in the body's overall health can help you appreciate the significance of maintaining a balanced diet that includes this essential nutrient.