It's clear from the comments and questions that nobody wants to be there. One woman declines most of the food samples and scowls at the fragrant spices that are passed around the room.

No one seems too sure what a low-sodium diet will mean — except possibly the end of life as they've always known it. Ronald Souza, an enthusiastic home cook who lives in Chinatown, sums it up: "Gonna have to throw out everything in my cupboard."

"This is a hard one," says registered dietitian Terry Leong, REHAB's food and nutrition services manager. She thinks it may be a more difficult adjustment for most people than cutting out fat or sugar.

REHAB dietitian Moanalia Bachiller, who teaches the low-sodium cooking classes, tries to emphasize the good news: "Salt, like sweet, is a learned thing. It's what you've been used to. That means you can change (your salt preferences). The trick is to gradually reduce the sodium in your diet."

Sodium, she explains, is a necessary nutrient that occurs naturally in food, even unsalted food, and also is found in water to a greater or lesser degree, depending on how the water is treated. Our need for sodium is so small, however, that we could meet it without ever touching a salt shaker, by just eating a balanced diet.

Normally, excess sodium passes through the body, but research has shown that some "salt-sensitive" people tend to retain sodium, which contributes to a number of health problems, most notably high blood pressure, a condition that puts you at risk for heart attack and stroke. Because there is no way to predict who is salt-sensitive, it behooves everyone, whether or not they have been placed on a low-sodium diet, to be mindful of the sodium they consume and to try and stay below the National Academy of Science's recommended standard of less than 2,300 milligrams per day.

The skeptical questions start as soon as Bachiller has explained these and other sodium basics.

The queries come in two forms, both indicative of denial:

• "There isn't a lot of sodium in (this or that favorite ingredient), is there?"

The answer is almost always yes, there is. That news is often met by a sigh, shrug or roll of the eyes.

• And, "it's OK to use a little bit (shoyu, ko chu jang, onion salt, Spam, etc.), isn't it?"

The answer is, what do you mean by "a little"? And how often would you use "a little"? And are you sure "a little" wouldn't lead right back to a lot?

Bachiller displays a variety of spices, spice mixtures and other flavoring agents that can be used to make up for the loss of sodium-rich ingredients. Souza scrunches his nose at the bottle of Mrs. Dash Seasoning Blend. Several around the table nod, and one woman whispers, with emphasis, "Pilau." Nobody's too enthusiastic about this herb and spice mixture frequently recommended as a salt substitute.

But the table is impressed when Bachiller passes around two samples of pepper — one pre-ground from the jar and one freshly ground. The difference is apparent even from a few feet away; the spice, fresh ground in a coffee mill Bachiller keeps only for spice grinding, has an inviting and layered fragrance. The pre-ground pepper smells faint and chemical. Appreciative nods and sniffs greet this demonstration.

The mood begins to lighten as information is shared. One woman recommends the salt-free seasonings found at Executive Chef. Souza gives everyone his recipe for cold ginger chicken. A lively discussion centers around salt-free shoyu. Everyone's eager to try it. Leong tells how to make namasu (Japanese pickled vegetables) without shoyu or salt, relying for flavor on a vinegar-sugar-ginger mixture — an idea met with interest and some skepticism.

The mood lightens considerably as Bachiller turns out one dish after another in which the lack of salt is noticeable but not at all hard to take. A taco salad with fresh-made cucumber salsa and chili-spiced hamburger is delicious — and with only 14 milligrams of sodium, instead of the heart-slapping 340 milligrams of sodium per serving in a product such as Lawry's Taco Seasoning Blend. Several people take seconds.

An easily-tossed-together bean and corn salad rates murmurs of approval, with no sense of deprivation.

And even a spiced chicken dish — a sort of curry made with pan juices and an Indian garam masala spice mixture — rated approval, although to our salt-sensitized palates it begged for a little more savor at 60 milligrams of sodium per serving. The dish sparked a lively discussion of possible variations.

As the group walks out after two hours, clutching plastic containers of house-made poultry rub, there's a happier buzz of conversation. But Leong knows what each individual faces: "The key to change is the frame of mind. If you go into it thinking your food is just going to be bland and flavorless no matter what you do, it's going to defeat you," she said. "You have to be willing to give it a try and stick with it until your tastes change."

Next week: Low-salt, local-style and Asian recipes.