Virtually any food you consume provides vitamins and minerals, although processed junk foods tend to have lower amounts than produce, low-fat milk and other nutritious foods. Most vitamins and minerals separate from other food components and absorb into your bloodstream through the small intestine. Some nutrients have additional steps that further delays absorption. For example, vitamins A, D, E and K are fat-soluble, meaning they absorb and are stored alongside fat. If you take a multivitamin with these nutrients but do not eat something with fat when you take it, your system may not pick up these vitamins. Vitamin B-12 absorbs differently than any other nutrient. This vitamin attaches to a protein called intrinsic factor in your stomach. Once B-12 and intrinsic factor combine, your small intestine is able to pick it up and send it to your bloodstream.