Dear Doctor. Blonz: My question is not about taking supplements, but whether there is a difference in nutritional value between those taken as pills and those taken in liquid or other form. A close friend tells me that the multivitamin pills I take are essentially useless as most of their nutritional value is never absorbed once they pass through the digestive system. She is convinced that liquid vitamins are the way to go because the body uses them almost completely. She mentioned that liquid supplements are 97 percent bioavailable and absorbable, while pills, capsules, and tablets are 3 to 20 percent absorbed. Please comment. – AH, Scottsdale, Arizona
Dear AH: We must first assume that the quantities stated on the Supplement Facts label are contained in the product (and that everything in this product is declared on the label). Assuming we are dealing with similar compounds and amounts, the key would be whether they are in solution when they reach the small intestine area where they are absorbed. It does not matter whether the product is in a pill, tablet, capsule, gel capsule, powder or liquid form before swallowing.
The USP, which stands for the United States Pharmacopeia, sets standards for strength, quality and purity of the ingredients. Their standards are that single-coated tablets disintegrate within 30 minutes in a simulated gastric environment. Delayed-release products should dissolve after one hour of holding together. This “delay” can be used on compounds that are at risk of being destroyed in the acidic environment of the stomach. Coatings that delay release are also used with compounds that are formulated for slow release rather than full release. These techniques are also used with medication.
