1. Biotin
Although biotin deficiency is rare, the following may include: hair loss, dry-scaly skin, cracking in corners of mouth (cheilitis), swollen and painful tongue (+magenta in color;glossitis), dry eyes, loss of appetite, fatigue, insomnia and depression
Symptoms of possible overdose may include the following: insomnia, excessive thirst and frequent urination
Purpose: metabolize carbs., fats and amino acids-all building blocks of protein
2. Although iron deficiency is rare, the following may include: dizziness, fatigue, lightheadedness, fast heart rate or palpitations, brittle nails, pallor or shortness of breath
Symptoms of possible overdose may include the following: upset stomach, constipation, nausea, vomiting, abdominal pain and diarrhea
Purpose: make hemoglobin, a protein in red blood cells that carry oxygen from the lungs to all parts of the body, and myoglobin, a protein that provides oxygen to the muscles