GLOSSARY

Goblet Cell secretes mucins supporting the mucus layer, distinct from the main absorptive cell's role.

The mucosa actively interfaces with food and microbes, combining selective uptake with defense. The intestinal barrier includes cells, junctions, mucus and immune functions rather than one sealed wall. Research permeability changes do not diagnose disease from fatigue or bloating alone. Persistent athlete symptoms warrant assessment; a promise to repair the gut immediately does not replace identifying the cause and maintaining adequate nutrition.

Villi are multicellular mucosal projections; microvilli are tiny extensions of individual absorptive cells. Microvilli form the brush border containing enzymes and transporters. Crypts are invaginations with renewing and specialized cells. These organizational levels differ. Greater surface supports absorption, but the appearance or name of a structure does not calculate the absorbed percentage of a person's meal or prove a supplement increases it.

Enterocytes absorb and process nutrients, goblet cells secrete mucus, and Paneth cells contribute antimicrobial defense. Enteroendocrine cells release food-related hormonal signals. This diversity shows that intestinal function involves more than rapid absorption. More of one nutrient does not necessarily enhance every cell type. Claims of improved uptake require functional evidence rather than simply naming a cellular mechanism or identifying a protective secretion.