GLOSSARY

Water-Soluble Vitamin Absorption uses varied, sometimes saturable routes; water solubility means neither unlimited absorption nor universal dose safety.

For example, record amount, food form and time before training when assessing a meal; neither a label value nor one blood peak alone establishes complete absorption and use.

Vitamins do not share one uptake route; water or fat solubility provides a useful starting point rather than explaining every exception. Food release, carriers, bile or binding proteins can contribute. Greater intake does not always increase absorption proportionally, and some excess is excreted. Athletes benefit from adequate food and identifying deficiency causes rather than competing for the largest package number or assuming every formulation behaves alike.

Fat-soluble vitamins commonly use fat digestion, bile and micelles during absorption, with carrier particles supporting transport. Some meal fat can assist, but an extremely fatty meal is not universally required. With fat malabsorption, simply increasing oral intake may not solve the problem; cause, formulation and body status also require consideration.

Food-bound B12 must first be released, then normally uses gastric intrinsic factor and absorption in the terminal small intestine. A small fraction can also enter by an independent pathway. Package amount is therefore not the absorbed amount, and gastric or ileal problems can impair status despite adequate food. These mechanisms help explain why dietary and medical correction strategies can differ.