Vitamin B1, also known as thiamine, is important for the nervous system, digestion, muscles, heart, and repairing alcohol-damaged nerve tissues. However, it is destroyed by high temperatures, alcohol, and coffee. A lack of vitamin B1 can cause tingling sensations, confusion, balance issues, loss of appetite, exhaustion, and difficulties concentrating. Good food sources of vitamin B1 include yellowfin tuna, beans, cooked corn, brussels sprouts, nuts, cereals, and veggie products.