COFFEE? TEA? What would I like in it? Cream? Milk? Sugar? Honey? Sweet 'N Low? Equal? Sweet One? Splenda?

Now, what went into that beverage? The first four are easy: dairy product, dairy product, beet or sugar-cane derivative, bee food. But what, exactly, are those final four, and the differences between them? And do I want them in my drinks and food?

Sweet 'N Low (and Sugar Twin) contains calcium saccharin, which is 300 times sweeter than sugar. Right out of the little packet, to my taste buds, it's the most bitter of the four, with a consistency like a slightly grainy powdered sugar.

Saccharin was discovered by a couple of American chemists in 1879, and its safety was first challenged in 1911, when a board of federal scientists decided the "adulterant" should be limited to products "intended for invalids." Sugar shortages during the two world wars eased the restrictions, and in 1958, when the Food and Drug Administration began to require its approval of food additives before they went on the market, saccharin was exempted along with other ingredients "generally recognized as safe."

Fitness news you can use Sweetness on the Web • For the FDA's history and overview of sweeteners, go to www.fda.gov/ fdac/features/1999/699_sugar.html. • The American Dietetic Association has a nice overview of sweeteners at www.eatright.org. • The Calorie Control Council (www.caloriecontrol.org) is a nonprofit association representing the low-calorie and reduced-fat food and beverage industry. • The Sucralose Toxicity Information Center is at www.holisticmed.com/ splenda/. • The Aspartame (NutraSweet) Toxicity Info Center is at www.holisticmed.com/ aspartame/. Over 55 and working out Americans older than 55 are the fastest-growing demographic age group in health clubs and fitness centers, according to a recently published study sponsored by the International Health, Racquet & Sportsclub Association. Its Health Club Trend Report found that just over 13 percent of the U.S. population (older than age 6) belongs to a health club or fitness center of some kind. Between 1987 and 2000, the number of Americans over age 55 who belong to a gym or fitness center grew by 380 percent; during the same period, total U.S. health-club membership grew by almost 90 percent, reaching a record 33 million members. Members over age 55 visited their club an average of 97 days in 2000, more frequently than any other age group. Ask Molly Questions on workouts, equipment or nutrition? Send them to Ask Molly, Pacific Northwest magazine, The Seattle Times, P.O. Box 70, Seattle, WA 98111, or e-mail mmartin@seattletimes.com

Another sweetener, cyclamate, was used in the 1960s but banned in 1970 when studies linked it to bladder cancer. After a 1977 Canadian study showed that saccharin caused bladder cancer in rats, the FDA proposed banning it for all purposes except as a tabletop sweetener. But the public was not ready to give it up, especially diet-soda fans. After all, at the time, saccharin was the only artificial sweetener on the market. And those rats had ingested saccharin equivalent to as many as 800 diet sodas a day. So Congress placed a moratorium on the ban, but required a label on foods with saccharin, warning that it might be a health hazard. It wasn't until last year that government officials decided there was no clear link between the sweetener and cancer in humans, and dropped saccharin from its list of cancer-causing chemicals.

Equal (also NutraSweet) contains aspartame, which was approved in 1981. A bit akin to grainy powdered sugar, it is slightly bitter and 180 times sweeter than sugar. It loses sweetness when heated, so isn't useful in baked goods. Aspartame contains two amino acids, phenylalanine and aspartic acid, which can be harmful to people with the rare hereditary disease phenylketonuria, those who have advanced liver disease, some pregnant women, and anyone at very high doses, when it may cause brain damage. The FDA requires a warning on the label of all products containing aspartame.

Sweet One (and Sunett) contains the simple sugar dextrose along with acesulfame-potassium (or acesulfame-k), which the FDA approved in 1988 and is 200 times sweeter than sugar. To me it is less bitter than saccharin and more than aspartame; its grain is almost as fine as powdered sugar. It can be heated, but for texture often is substituted for only half the sugar in a recipe.

The most recently approved (in 1998) is sucralose, brand name Splenda. It's the least bitter of the four, is 600 times sweeter than sugar but tastes most like it, for good reason: It's made from sugar, by replacing three hydrogen-oxygen groups on the sugar molecule with three chlorine atoms. It can be used in cooking and baking as well as a tabletop sweetener.

Despite all that FDA approval, Web sites about artificial sweeteners abound. In a single search, pages sponsored (not always obviously) by manufacturers pop up alongside those questioning the safety of artificial sweeteners. Some play off the idea that anything natural is healthful and anything artificial is dubious. Some suspect the FDA is in cahoots with the manufacturers of artificial sweeteners. Some simply don't trust the government.

From what I can tell, it's nearly impossible for the average consumer — or journalist — to weigh all that information and reach any firm conclusions

In the meantime, three other sweeteners are under FDA review. Two — neotame and alitame — are descendants of aspartame. The third is cyclamate, which is cycling back around with a petition for its reapproval.

For me, what comes to mind whenever I'm presented with an artificial sweetener is something completely unscientific, something a Japanese friend said once when she passed up the offer of a Teflon pan:

"I don't trust it."

Molly Martin is assistant editor of Pacific Northwest magazine. Ellen Banner is a Seattle Times staff photographer.