Vitamin B-3 (Niacin)

Functions:

• Contributes capture and use energy released from carbohydrate, fat and protein
• Assist in the manufacture of body fats
• Helps maintain normal nervous system functions
• Tryptophan is a precursor of niacin

Deficiency:

• Pellagra:skin disorders, nervous and mental disorders, diarrhea, indigestion and fatigue

Recommended Requirement 

• 16 mg
• High intake over 500 mg/d cause rapid heart beat, nausea, headache, cramps, decreased liver function  

Sources:

• Dairy products, nuts, dried beans, grains, cereals, meats