Q: How much of the sodium in a can of soup is absorbed by the solid contents and how much remains in the liquid? I would think the solid contents would absorb so much of the salt that there would be less in the liquid. You guessed it: To reduce sodium, I eat the solids and throw out the liquid.

A: That’s probably impossible to answer, says Anna LaBarre, a registered dietitian in Durham, N.C., with the Rice Diet Program, which works with patients on weight loss and heart disease through a whole-foods, no-salt-added diet. For one thing, the solids in soup vary so much.

The only study LaBarre knew of that comes close looked at canned beans. That study found that if you rinse canned beans, you can remove as much as 40 percent of the sodium. But the liquid in canned beans is very different from soup.

You also might be losing valuable nutrients by discarding the soup liquid. When you boil vegetables, much of the nutrients end up in the cooking liquid.

Instead of discarding the liquid, LaBarre suggests that it would make more sense to simply find a low-sodium canned soup and eat the whole thing.