Capsules are gelatin containers that dissolve quickly, and in most cases, are the best choice. Because they're not compressed like the tablets, you will typically have to take two of them to equal one tablet, but always follow label instructions or those of a physician.
One important thing with vitamin supplements is that you want to make sure you absorb as much as possible; otherwise, you are just wasting your money. Studies have shown that individual vitamin isolates found in supplements are only about 10 percent absorbed, while vitamins that are derived directly from a fresh plant source are 77-93 percent absorbed. Minerals have an even lower absorption rate -- 1-5 percent. But from plants like raw broccoli, the minerals are 63-78 percent absorbable.
The reason for this difference in absorption is that in nature, each vitamin and mineral molecule is attached to a protein molecule. That's why you must take your vitamin supplements with meals -- unless stated otherwise on the label. During digestion, only about 10 percent of the vitamin and mineral molecules, aided by enzymes, will attach to the protein molecules found in your food allowing them to be absorbed and used by your cells. Without these accompanying proteins, the body will see the vitamin isolates as a foreign substance and filter them out. That's why you might have noticed bright yellow urine after you take a vitamin -- that's your body's way of getting rid of chemicals it thinks it can't use.
When selecting a vitamin supplement, make sure it has adequate amounts of the vitamins and minerals you want. Remember only about 10 percent of what is in the supplement will be absorbed. Look for the BP (British Pharmacopoeia) or USP (United States Pharmacopoeia) designation on the label. You will find the USP or BP initials next to the vitamin, and this designation means the vitamin isolates are of the highest quality and are easily dissolved in the digestion process.