The recommended daily allowance for vitamin B1, also known as thiamine, is 1.2 milligrams a day. It's not only necessary for mental health it's also great for your hair, skin, muscle growth, appetite, and digestion. To my drinkers and partiers out there, you need to know that alcohol actually destroys vitamin B1. As little as one drink a day can cause a vitamin B1 deficiency. Some early symptoms of vitamin B1 deficiency include depression, mood shifts, and mental dysfunctions. Vitamin B1 deficiency is actually not uncommon today because we eat a diet filled with refined, processed foods. To avoid becoming deficient make sure you're including plenty of B1 vitamin enriched foods. These foods include whole grains, liver, grass fed organic meats, nuts, and seeds. If you're eating a healthy diet, but are experiencing some of the symptoms I mentioned, it would be a good idea to get a B1 complex supplement. That way you'll know for sure that you're getting enough of the B1 vitamin.