Dear Matthew Alice:

While taking my daily vitamin, I paused to study the back of the container. the elements that have me puzzled are the "inactive" ingredients. What do they do or not do?

D.S. and J.S., University Heights

The best explanation of the purpose of inactive ingredients might be the story of Winslow and Peaches, two of the more inert members of the Alice clan — some remote twigs from Ma Alice's side of the nut-bearing family tree, we were told (but could never actually prove). Their theoretical relativity ensured them an invitation each year to Ma's bacchanalian family reunion — a sort of combination bination rugby tournament, swap meet, and prosperity seminar, with plenty of beer. Winslaw and Peaches always showed up early and invariably wedged their large butts into the two best lawn chairs closest to the refreshment table and spent the rest of the day reading magazines. Every year we'd beg Ma to drop them from the guest list, and every year she'd refuse so she wouldn't hurt their feelings. No Winslow, no Peaches, no party was the rule. The duo contributed nothing to the merriment, but without them, there'd be no party at all. Winslow and Peaches were inactive ingredients.

Pharmaceutically speaking, inactive ingredients contribute nothing to the purpose of the medicine but are necessary for manufacturing the tablet to begin with. Not knowing what brand you use, I can't say for sure which inactive ingredients yours contains. But here's an example of the chemical equivalents of Winslow and Peaches in one such vitamin tablet. Microcrystalline cellulose, hydroxypropyl methylcellulose, magnesium stearate, acetylated monoglycerides, vegetable starch, and silica (derived from rocks) are blended with the active ingredients to keep them evenly mixed and flowing smoothly in the tablet-making process. Lactose (milk sugar) is only a filler, so the tablets won't be the size of fly specs. Talc (more pulverized stones) is used to line the molds the pills are formed in and is sometimes added as a filler. Thrtrazine is yellow dye no. 5, a coloring agent. Dicalcium phosphate is a preservative, and the tablet coating contains ethylcelluJose, stearic acid, and carnauba wax (yes, a food-quality version of the palm-leaf exudate they spray on your car at the car wash).