Vitamin B1 aka Thiamine | Vitamin Breakdown
B1, more important than you might think. Some symptoms in the early stages of thiamine deficiency include irritability, fatigue, apathy, abdominal pain, drowsiness and poor concentration. Later stages of thiamine deficiency are much more severe and can manifest in a number of ways. A few manifestations are tachycardia (fast heart beat), vomiting, heart failure, weakness, itching, blue skin color, numbness and memory loss.