Thiamin, also called Vitamin B1, is a water-soluble vitamin that functions as a coenzyme to help release energy from the foods you eat. It is generally better to get your vitamins from foods, rather than pills, but many healthy experts recommend that you take a daily vitamin/mineral supplement as a safety net to fill in the gaps in your diet.
Many foods contain small amounts of Vitamin B1, but here is a list of foods that are a more significant source.
Pork, Fortified cereals, Fortified and enriched grains and products made from them, including bagels, biscuits, breads, crackers and pasta, Soy milk, Tomato juice, Split peas, Lentils, Sunflower seeds, Macadamia nuts, Cashews, Pistachios, Winter squash--baked and mashed, including acorn, butternut, Hubbard, buttercup, Lima beans, Navy beans, Sweet corn, Green peas, Wheat germ, Watermelon, Potatoes, Asparagus, Oranges, Pineapple canned in its own juice.
B vitamins are water soluble.
Water-soluble vitamins, as the name suggests, can be dissolved in water, so they are absorbed directly into your blood stream. They travel freely though the blood to the sites in your body where they are needed and any excess can be removed by the kidneys and excreted through the urine.
Vitamins in foods can be destroyed by light, heat and oxygen.
Storage methods and food preparation techniques will affect the amount retained by the foods. To minimize this problem, refrigerate produce in airtight containers, and during preparation, steam or cook vegetables lightly, avoiding high temperatures and extended cooking times whenever possible.
Note: Alcoholics are at particular risk for a B vitamin deficiency, since alcohol inhibits the ability of the body to absorb vitamins. This means that even if an alcoholic is eating lots of nutrient-rich foods, the body may not have access to enough thiamin to maintain good health. There could also be a thiamin deficiency, if alcohol is replacing food in the diet.