Cumberland Packing, the company that manufactures Sweet'N Low, occupies a boxy building across the street from the Brooklyn Navy Yard. It sits amid the factories of Fort Greene, the last of New York City's vanishing industrial base. The neighborhood is ringed by housing projects, dark windows looking out on the long skies over Williamsburg.

During peak hours at Cumberland, the packing machines rattle and the building vibrates and the workers shout over the racket, and all of this builds into a roar. As the packets are filled, saccharin dust drifts into the air, and you breathe it into your lungs. It flavors everything sickly sweet. To make Sweet'N Low, Cumberland uses tons of cream of tartar, dextrose, and saccharin each day. The ingredients are combined in a mixing room on the second floor, a lab where workers wear bathing caps and booties. You see them behind glass, stirring the pre-mix. This product is fed into tremendous whirling, Sheeler-esque machines, which cut and load it into packets and dump them onto a conveyor belt that winds through the factory like a river. Every packet is tested and weighed. On the factory floor, the conveyor belt breaks into tributaries, each headed for a different machine. Ladies in hairnets direct this flow into boxes, which totter off to the shipping bay, where they are loaded onto trucks that carry them all over the region.

In the 1950s, Cumberland Packing was a prosperous little factory, part of the belt of industry that stretched along the Brooklyn waterfront. My grandfather Benjamin Eisenstadt, who started Cumberland in 1946, employed a few dozen people. The company grossed perhaps a hundred thousand a year, most of it plowed right back into the factory: new machines, more workers. Ben brought home just enough money to buy a car, support a family, send his kids to summer camp. He was packing sugar, duck sauce, perfume, and tokens. My mother, who worked at the factory when she was in high school and college, said she could tell the nature of a run by the smell in the air. Cumberland had become a transit station, a place where the raw material of the borough was given shape and sent into the market.

In 1956, Ben and his son Marvin, who would eventually take over the company, began the research that would culminate, later that year, in the invention of Sweet'N Low. There are legends about this discovery, as well there should be. It's the place where the stream goes under the rocks and emerges as a swift and dangerous river, where the needling problems of a middle-class Brooklyn family become the soap-opera stuff of the super-rich.

According to legend, the invention was an expression of character. That is, the nature of Sweet'N Low can tell you about the nature of Ben, is an extension of Ben, or is Ben himself in another form. Sweet'N Low as a sacrament. Sweet'N Low as the holy wafer. Take it onto your tongue and let it dissolve. The rush of sweetness is followed by a bitter aftertaste. That aftertaste is the soul of Ben. My mother said the spark came when Ben was on a diet. Ben was always on a diet because he was never happy with who he was—a psychosis that runs through the family. "Because of this diet, Grandpa Ben was not eating anything with sugar," said my mother. "In those days, the only substitute was Sucaryl. It came in little pills that you carried in a vial. You put one into a cup of coffee. Or there was a liquid that came in an eyedropper. If you were having iced tea, you might add two drops. But the liquid was too sweet. And the pills never dissolved. My father loved grapefruit. He would crush the pills and spread it on the grapefruit, but that never really worked. It bothered him. It was a problem he wanted to solve."

Ben launched the product in 1957, at first positioning it as a medicine, an aid to diabetics.

For Ben, grapefruit is like the apple of Newton, that part of the material I world that cracks him on the skull and jars loose the obstruction.

"I have no idea how he came up with it," my Aunt Gladys told me. "Yes, he was on a diet, but I don't know. People were dieting and using saccharin, so, O.K., I guess he decided, 'Let's invent a sugar substitute.'"

Is this what happened?

Well, Ben was on a diet and he did sprinkle mashed-up saccharin-and-cyclamate pills on his grapefruit, but he did not take the logical next step on his own. The idea for an artificial sweetener in powder form was in fact brought to him by the executives at a long-defunct pharmaceutical company. These men asked Ben if he could devise a sugar substitute that could be packed by Cumberland in the same way the company was packing sugar. Fake sugar, real packets. To these men, fake sugar was imagined less as a food than as a medicine. It would be sold to hospitals and drugstores. It would be used mostly by diabetics. With this simple idea, the pharmaceutical executives were offering a solution to a problem new in history, the American problem of plenty. Not the scarcity of food, but too much. Too many burgers, too many shakes, too many candy bars, too many calories.

"The drug company came to us," said Marvin. "They wanted us to make a sugar substitute. At that time, there was just Sucaryl, put out by Abbott Laboratories."

Even if they did not know it, Ben and Marvin were entering into a plot to overthrow sugar, which had been the king of the Western diet for 500 years.

In 1957, Ben hired a chemist to help him devise a mixture that would approximate the look and feel of sugar. Much is made of Marvin's chemistry degree, but, in truth, Dr. Kracauer was the professional on the project. Paul Kracauer is like Pete Best, the first drummer of the Beatles, mostly expunged from lore, but the name endures on the patents. When my mother mentions his name, it's with drama, like the name of a villain in a silent movie: "Dr. Kracauer." I picture it written in wavy freak-show letters: DR. KRACAUER RETURNS! I guess this is because of the name itself, which has an Eastern European concentration-camp ring, but also because of my sense that here is the evil genius behind it all.

In devising the formula, Ben was especially wary of saccharin's aftertaste. "In many cases this bitter aftertaste actually makes the person nauseous," Ben wrote in his patent application. The saccharin would therefore have to be cut with a neutral substance. Several years before, the scientists at Abbott Labs had come up with a formula considered the industry gold standard. The 10-to-l mix: 10 parts cyclamate, which is not as sweet as saccharin, but has no aftertaste, and 1 part saccharin. A perfect complement. When the cyclamate is combined with saccharin in an amount that equals the sweetness of one teaspoon of sugar, it yields a pill the size of a mini M&M. The aftertaste is there, but muted. If Ben wanted to fill an entire packet with the formula, he would need another ingredient to bulk up the mix and approximate the texture of sugar.

Marvin says he found the missing ingredient in a cookbook. According to an old recipe, lactose bulked up food and leached out taste. With the addition of lactose, Ben was able to perfect the formula that became Sweet'N Low. Whereas saccharin had been an artificial sweetener, this was fake sugar: a counterfeit, part of the postwar process whereby the world of our grandfathers would be replaced by a facsimile. But when Ben and Marvin returned to the pharmaceutical company, the executives hardly seemed to remember them, were not sure what Ben was talking about, and did not want to taste that cup of coffee, because they were no longer interested. "We had done all this work and they just didn't care," Marvin told me. "And we thought we had really accomplished something. Put it in a cup of coffee and it tastes like sugar. But they changed their mind. Maybe they thought the market was too small."

The big moment from which all the other moments flowed was therefore brought about not by an act of genius or will, but out of a first-generation determination not to let good work go to waste. "Well, my dad was angry, and so was I," said Marvin. "We had worked very hard and very long on this and hated to watch it go down the drain. So we decided, you know, let's just make it and pack it and distribute it ourselves."

By showing the government that this new saccharin formula, with lactose as its secret ingredient, was the closest fake thing to real sugar, Ben and Marvin won a "use patent." For 18 years, only Cumberland would be allowed to manufacture the formula. "Now, of course, those 18 years have gone by," Marvin told me. "But once you develop that magical brand name, nothing can touch you. If someone put out the exact same product without our name, we would outsell them eight to one."

From there, it was just a matter of marketing: What will the product be called? What will the packet look like? What color will it be? Where will it be sold? To whom will it be sold?

When I asked Marvin who had been responsible for what, he told me that he had made most of the big decisions, but Ben had been "an inspiration."

"The product was developed by Ben and Dr. Kracauer," said my father. "I watched it happen. Marvin kept the machines running. He was good at fixing things. He was like a mechanic. His job was to keep those things going."

When pressed for specifics, Marvin said, "Well, the name Sweet'N Low was [Ben's] invention. It was a phrase from his favorite Tennyson poem."

Marvin mentions this often, but it's not exactly true. As Huck Finn would say, it's a stretcher, a way to class up the joint. The name Sweet'N Low does not come from Ben's favorite Tennyson poem, but from a song written with the words of the poem—the sheet music credits Alfred Lord Tennyson and Joseph Barnby—that had been a hit in the early 1900s, when Ben was a kid. Up until a few years ago, if you called Cumberland and said, "This is Rich Cohen. I am trying to reach my Uncle Marvin," the hold music was "Sweet and Low," a melancholy dirge on a loop, what the military band plays as the boys march to hell.

Marvin said that he came up with the packet color, that he entertained and rejected blue because blue does not occur in nature. But this sounds to me like Marvin reading a criticism of Equal—which would not appear for more than 20 years—back into the historical record. I say this because (1) blueberries; (2) sky. Gladys told me that it had been Ben who chose pink because Ben thought pink would stand out among the white sugar packets on diner tables. The packet and the logo were designed by my Aunt Barbara, an amateur artist who, on family vacations, used to paint funny faces on tennis balls. Her work on the packet was just beautiful: the name of the product as notes on a musical staff. It has become a classic, as much a symbol of plastic America as the soup cans of Andy Warhol.

Ben launched the product in 1957, at first positioning it as a medicine, an aid to diabetics. He sold it to restaurants and hospitals, simply adding Sweet'N Low to the river of product already flowing out of the factory. Those first shipments were devoured. Packets were swiped from restaurants and stolen from hospitals. People called Cumberland. They wanted to buy boxes wholesale. Ben and Marvin had tapped into the Zeitgeist; they had boarded a bullet train called Fat but Still Hungry. The way you go to the airport and step on a moving walkway and it turns out that walkway is moving a thousand miles an hour. "Then it really happened," Marvin told me. "We got a call from the head buyer of the A&P, the supermarket chain with hundreds of stores across the nation. Manufacturers would kill to get their product in there. They told us they wanted to start stocking Sweet'N Low. That's when we knew this was really going to be something big."

Ben bought billboards on buses. The first ads showed a woman holding a glass of iced tea over the words I CALL MY SUGAR SWEET'N LOW.

Within a few months of the cyclamate ban, sales had tripled. Sweet'N Low was No. 1.

A t the time of Ben's use of it in Sweet'N Low, cyclamate had long been of concern to the Food and Drug Administration. It had been discovered in 1937. While experimenting with anti-fever drugs, a University of Illinois chemistry student named Michael Sveda set down his cigarette on a lab bench. When he picked it up and took a drag, it tasted as if it had been dipped in syrup. In the course of tinkering, Sveda had freed a hydrogen molecule from a bond, which resulted in a compound 30 times sweeter than sugar. Though still not as sweet as saccharin (which was also discovered accidentally, in 1879), the compound was sweet enough to be used in quantities amounting to zero calories. Unlike saccharin, it had no aftertaste.

Sveda licensed his discovery to Abbott Laboratories, which within a few years was turning out great mountains of the stuff. By 1953, scientists at Abbott had devised the cyclamate-saccharin mixture that was soon being used in Kirsch's No-Cal Cola, DietRite, Tab, and Sweet'N Low. In 1959, after an extensive study, the F.D.A. added cyclamate to its list of approved preservatives. Because it was assumed that the use of cyclamate would be limited almost exclusively to diabetics, the approval was explained as a lesser of evils: better a diabetic use cyclamate than live in a world with no alternative to sugar and so be tempted into a wilderness of jelly doughnuts.

In the 1960s, however, the F.D.A. reconsidered: cyclamate was not being used exclusively or even mostly by diabetics, but, like saccharin, had crossed into the mainstream, where it was being ingested by millions of perfectly healthy calorie counters. To the chemists at the F.D.A., the trend seemed reminiscent of a long history of unnecessary disasters, most memorably the tragedy of thalidomide, a pill prescribed to women for insomnia and morning sickness. It was not approved for sale in the United States, because a medical officer of the F.D.A. at the time, Frances Kelsey (her name deserves to be remembered), said that it had not been tested nearly enough. Guilty until proven innocent. In the early 1960s, thalidomide was prescribed widely in Europe, South America, and Canada. When it was taken in the first months of pregnancy, the birth defects were to the parts of the body that develop early: fingers, arms, and legs. According to the F.D.A., even a single dose of thalidomide during early pregnancy could cause major defects. Ten thousand babies were born severely affected. They came to be known as thalidomide babies, as if the sedative had joined with the genetic code to create a new species. Babies were born with flippers instead of arms, or with long forearms and no hands, or with no arms and no ears. Or their eyes didn't work, or their nervous systems, or their hearts. As you get close to the border with Canada, where the pill was prescribed widely, you see them, almost middle-aged, paying for a few bad months in the 1960s. It was a sad triumph for the F.D.A., vindication of the "slow as molasses" style that had made it a target of the drug companies.

When the word "cancer" hit, people panicked, entire product lines were wiped out.

In the late 1960s, a series of experiments suggested that large intakes of cyclamate had coincided with an uptick in cases of cancer. The incidences were rare, the tests inconclusive, but the mere mention of the word "cancer" tripped the Delaney Clause, a rider to the Food, Drug, and Cosmetic Act that says that any food additive or preservative shown to cause cancer in any living thing must be banned. No questions. Zero tolerance.

In late 1969, the F.D.A. announced its decision to remove cyclamate from its list of approved preservatives and ban its use in foods and nonprescription drugs. When the word "cancer" hit the newspapers, people panicked. Diet products were pulled from the shelves, a river of cola went hissing down the gutters. (It makes me think of the chapter in A Tale of Two Cities called "The Wine Shop," in which a mob kicks open a cask and wine runs in the streets, and in it you see the blood of the coming revolution.) With one stroke, entire product lines had been wiped out. Tab: gone. Diet-Rite: gone. Diet Crush: gone. The tabletop sweeteners that competed with Sweet'N Low (Wee Cal, Sweet Mate): gone. (The diet sodas would eventually come back; the sweeteners would not.) Factories closed, and hustling, Ben-like entrepreneurs accepted corporate positions. The term "job security" came to have a nice ring. Everyone was wounded, everyone bled. Everyone except Ben and Marvin. For Ben and Marvin, the cyclamate ban came as a blessing. "From every disaster we made a victory," Marvin told me. "Because we took advantage of it." Because they were prepared.

Because they knew the ban was coming. But how?

Cumberland Packing bought its cyclamate from Abbott Labs, which was headquartered in Abbott Park, Illinois, just a few miles from Libertyville, where my parents were living. My mother knew many of the company wives. From playground scuttlebutt (in such towns, the wives are like the astronaut wives in The Right Stuff) my mother learned that cyclamate would soon be banned and that Abbott would not fight the ban. If a company the size of Abbott chose to fight, the works could be gummed up for years, long enough for the Diet-Rites and Tabs to adjust and be ready.

"Abbott was supposed to fight the ban," my mother told me. "But I found out they wouldn't. I called my father and told him. Because of that, when the ban did come, he had a head start on the entire industry."

But according to Marvin, he was ready for the ban simply because he "had a gut feeling." It was because of this feeling and because of his cautious, plan-for-every-contingency style that, he said, "belt-and-suspenders Marvin developed a product without cyclamate."

In fact, Ben and Marvin already had notes for an alternative formula which they had drawn up years before while searching for a perfectly kosher Sweet'N Low. (Because the original formula contained lactose, a dairy product, it could not be used by religious Jews during or just after meals—in a cup of coffee, say— that included meat.) Marvin dug out these plans, got together with his "key personnel," and went to work. Once they had stripped away the cyclamate, the saccharin aftertaste re-emerged like a repressed memory. Marvin tried everything, in the end finding the answer (once again) in a cookbook: cream of tartar, an ingredient that adds bulk without adding calories, and dextrose, an ingredient that leaches out aftertaste.

Immediately after the ban was announced, but before it was enacted, Ben called his distributors and buyers and told them to junk the old product and he would send them boxes of Sweet'N Low made without cyclamate. "We got rid of all that stuff, and we didn't have to," Marvin said. "This was before the ban went into effect. Then we put out the new stuff. We borrowed over a million dollars to cover all the costs. There were headlines in the papers saying that Cumberland Packing, the makers of Sweet'N Low, have reformulated their product. They showed us in Chicago dumping old Sweet'N Low with cyclamate into a landfill."

If the cyclamate ban had not been enacted, Cumberland would have been out millions of dollars for research and junked product. But when the ban was enacted and all of Sweet'N Low's competitors were pulled from the shelves, Ben and Marvin were perfectly positioned, with boxes of their new cyclamate-free sweetener already in stores. The belt snapped, the suspenders held! In those weeks, when the vacuum left by Wee Cal and Diet-Rite and Tab opened up, the pink packets swirled in. According to articles that ran in The New York Times on October 20 and 21, 1969, General Foods, Pillsbury, Pepsi-Cola, Coca-Cola, and Royal Crown were all ready with cyclamate-free products within a few weeks of the ban—but those few weeks made all the difference. Cumberland Packing went from being a midsize company in a competitive field to being virtually the only company in a major industry. Within a few months, sales had tripled. Sweet'N Low became No. 1.

In 1985, Equal outsold Sweet'N Low. NutraSweet had become the No. 1 brand.

In the 1970s, the F.D.A. turned its attention to saccharin, which had long been an obsession of the fake-food cops. With the banning of cyclamate, these officials had shown that it was possible to take on the pharmaceutical industry, even with big money at stake. (A saccharin ban would mean the loss of $1.9 billion a year to the diet and pharmaceutical companies.) During the early 70s, several saccharin studies were under way. The most damning of these was done in Canada, where 100 rats were fed monster doses of the artificial sweetener. It was shot directly into their bodies— the equivalent of 800 cans of Diet Coke a day. Among the second generation of rats, exposed to saccharin in utero as well as during their lifetime, 14 developed bladder tumors. Twelve of them were male. A mega-dose of saccharin, it was concluded, results in bladder tumors in male rats.

If it causes cancer in male rats, will it do the same in men?

The Canadians removed saccharin from the market in early 1977. Once a link to cancer had been established, the Delaney Clause kicked in and Sherwin Gardner, the commissioner of the F.D.A., really had no choice. In March 1977, saccharin was banned in the United States. On March 10, 1977, The New York Times ran the story on the front page: F.D.A. BANNING SACCHARIN USE ON CANCER LINKS. In that moment, it was Cumberland's turn to teeter on the edge of the abyss. In the ensuing weeks, Marvin argued, pontificated, wisecracked, shouted his head off, and complained. He went on TV and radio. He talked to anyone who would listen. He became the champion of the diet economy. In a New York Times story headlined INDUSTRY RESPONDS TO BAN OF SACCHARIN, Marvin said that to equal the amount of saccharin given those rats "an individual would have to drink diet soft drinks at the impossible rate of more than 1,000 bottles a day." In another story, he said, "Your organs would have to be bathed in the stuff." Reading these articles today, you can feel the panicky energy of my handsome uncle. The Calorie Control Council, a lobbying group then headed by Marvin, took out a full-page ad in national newspapers that showed my uncle buried neck-deep in pink packets. According to the copy, this was the amount of Sweet'N Low a person would have to eat every day to approach the intake of the study rats.

The letters poured into Congress: doctors worried about diabetics; dentists worried about tooth decay. For the first time in our history, the ugly word "gingivitis" was whispered in the corridors of power. More than the gap-toothed or the insulin-starved, it was the calorie counters who made the difference. When weighing the possibility of a future tumor against the here and now of a skinny life, the consumers chose the here and now. In the week after the ban, Congress received more than a hundred thousand letters, more than received in any comparable period during the Vietnam War.

When the politicians finally weighed in, the bureaucrats were relieved: the F.D.A. had strayed beyond its depth. It did not understand the crazed nature of its own time. On March 18, 1977, a week after the ban was announced, Ted Kennedy, the chairman of the Senate Subcommittee on Health and Scientific Research, moved for a delay. That June, Senator Kennedy pushed through a moratorium: the ban would remain on the books but would not be enforced. The effects of saccharin would be studied further. In the meantime, all saccharin products would carry a warning. The entire matter would come back before Congress in two years, at which time either the ban would be enforced, or saccharin would be cleared, or the moratorium would be extended. In November 1977, Jimmy Carter signed the Saccharin Study and Labeling Act into law.

The Sweet'N Low packet would now carry the label: "Use of this product may be hazardous to your health. This product contains saccharin, which has been determined to cause cancer in laboratory animals."

"Ted Kennedy proposed that," Marvin told me. "And it was unfair. Because it said the product causes cancer in animals. But it was only rats."

The warning would appear on all saccharin products until Congress voted to remove the label in 2000 after a joint study by the National Cancer Institute and the F.D.A. found that saccharin was safe for humans. In January 2001, in the last days of his presidency, Clinton signed the bill, and the saccharin ban officially ended.

Following the announcement of the saccharin ban, there was no F.D.A.-approved artificial sweetener, no "safe" alternative to sugar. The result was a race like the race to the moon. Who will find the alternative to the alternatives? Who will plant the flag? Because they had long been the market leader and the owner of the most famous brand, Ben and Marvin would have had a great advantage in this race. They would not have been starting at zero. They would have been building on their existing dominance. Nor would they have had to devise a clever way to introduce a strange product from the laboratory. They could instead have sold any sweetener as new and improved Sweet'N Low, in the same way that Coca-Cola introduced its new formula as New Coke. But Cumberland ducked out of the race, or did not even realize that a race was under way, and instead directed its time and resources to saving saccharin. But the market opened and the conglomerates flowed in.

In 1977, GD Searle, an Illinois-based chemical manufacturer, brought in squinty-eyed Donald Rumsfeld to re-structure the company and presumably get its chemical sweetener, aspartame, approved by the F.D.A. The company had been founded by Gideon Daniel Searle, who, in the years just after the Civil War (he was a twice-wounded, shell-shocked veteran), built a chain of pharmacies in Omaha, Nebraska, then opened an elixir factory in Illinois, where he made his first fortune with Dramamine, a motion-sickness pill perfectly suited for the new, footloose, travel-happy American middle class. In 1925, Searle moved his company to McHenry County, Illinois, then to Skokie, where, in 1965, aspartame was discovered by accident.

A chemist named James Schlatter had been searching for a formula to treat ulcers and heartburn when the potion bubbled onto his hands. He licked his fingers: Eureka! It was 200 times sweeter than sugar and could be used in quantities so small as to amount to no calories. Aspartame is made of two amino acids: phenylalanine and aspartic acid. When they enter your system, they produce methanol, which, according to Merriam-Webster's Collegiate Dictionary, is "a light volatile flammable poisonous liquid alcohol." Aspartic acid is sometimes classified by critics as an excitotoxin, a family of chemicals that excite the nerves and pathways in your brain—think of the old footage of a carpet of cluster bombs lighting up the jungles of Vietnam. In 1966 the Journal of the American Chemical Society described the new formula as a result of "an accidental discovery of an organic compound with a profound sucrose (table sugar) like taste. Preliminary tasting showed this compound to have a potency of 100-200 times sucrose depending on concentration and on what other flavors are present and to be devoid of unpleasant aftertaste."

Sweeter than saccharin; no aftertaste.

The executives at Searle saw the commercial implications immediately; these were hard to miss. Yet they had a terrifically hard time getting their new compound approved by the F.D.A. In every test, something came out wrong. Over time, a sinister aura grew up around aspartame, rumors which have never entirely disappeared. Just go to the Internet and look up all the freelance nutters who have attached the compound to a conspiracy that traces a line from Donald Rumsfeld to Ronald Reagan to airplane crashes to early death. They say it does freaky things to your brain, knocks you for a loop, blows a hole in the cortex. They sing of headaches, seizures, blackouts, memory loss, lesions, slurred speech, mood swings, anxiety attacks, coma, extremity numbness, and loss of limb control.

The NutraSweet Company responds to these rumors and complaints on its Web site: "The overwhelming body of scientific evidence clearly demonstrates that aspartame, even in amounts many times what people typically consume, is safe and not associated with adverse health effects. The FDA has investigated alleged complaints since 1982 and states that there is no 'reasonable evidence of possible public health harm' and 'no consistent or unique patterns of symptoms reported with respect to aspartame that can be causally linked to its use.'"

"We were running [an aspartame] test product here, and the girls, some of the girls, just couldn't run it because they would get hives," Marvin told me. "The dust. Some people are allergic to it, and it affects their vision, and they don't want to take a chance with an airline pilot. [Pilots] are not allowed to drink diet sodas, they're not supposed to, two hours before their flights."

Over time, a sinister aura grew up around aspartame, rumors which have never entirely disappeared.

The F.D.A. rejected aspartame in the 1960s and again in the 1970s. Because of certain discrepancies. Because of certain worrisome patterns in the tests. Since the market at the time was already well served by cyclamate and saccharin, there was no reason to introduce a questionable new compound into the food supply. Then cyclamate was banned. Then saccharin.

It was a scientific study commissioned in the late 1970s that finally convinced regulators that aspartame was safe. According to the study, the compound is indeed a danger, but only for the tiny sliver of the population that suffers from a hereditary disease called phenylketonuria (PKU), an enzyme deficiency in the brain that, if acted on by phenylalanine, can send a sufferer into seizures and damage the brain. Babies with PKU, if exposed to aspartame, can suffer mental retardation. (Diet Coke cans carry a warning for those with PKU.) With this new study, the results from early tests had been explained: it was just a few people with a disease you've never heard of. In 1981, after 20 years of controversy, aspartame was approved.

There tend to be two explanations for this approval: (1) executives at Searle, knowing their product was good and true, pressed on, searching for and then finding the reason for the occasional seizure; and (2) executives at Searle surely suspected that their wonder chemical left a wake of blinded, jittery, panicky amnesiacs, but pressed on anyway, because that's corporate America, until just the right cards were dealt—a cyclamate ban, a saccharin ban, a fat-obsessed nation, a market without an unbanned artificial sweetener, and, most important, a Republican administration. For two decades, aspartame had failed to win approval. Then Ronald Reagan was elected president, and Donald Rumsfeld, while keeping his position at Searle, worked on the president-elect's interim foreign-policy team. Soon after Reagan was inaugurated, Searle re-applied for approval of aspartame. Within a few months, Reagan had named a new head of the F.D.A. and the chemical got the green light. Rumsfeld had correctly recognized that Searle's problem was not scientific; it was political.

Searle created a new division, the NutraSweet Company, to market aspartame, the first new sweetener on the market in 25 ¼# years. The company registered two trademarks: Equal, the tabletop sweetener (fake sugar) it would introduce in 1981, and NutraSweet, the food-and-drink additive it would introduce in 1983.

"I was told we were going to lose our business," Marvin said. "I was not panicked, for two reasons. One, I felt that we'd been in the market for such a long time people would not desert us. Two, there were questions about Equal, health things. Three, taste. For people used to Sweet'N Low, [Equal] wasn't sweet enough."

Splenda is sugar remade, a molecule stolen from God, painted, and thrown back on the market.

The launch of Equal and NutraSweet was brilliant; not Harvard Business School or Wharton brilliant, but Sun Tzu or Von Clausewitz brilliant. It was a military campaign. It was a slaughter. Searle, not content with just a good debut, wanted to overwhelm the field.

In 1983, Searle sent a gumball sweetened with NutraSweet to millions of homes. It was like the drug dealer giving the kid on the playground a taste of cocaine, saying, "Pass it around, let 'em all try it. You know where I am if you want more." That summer, kids talked about the new miracle product the way Columbus once spoke of the antipodes. Here I speak not as a historian or scholar but as one who was lucky enough to be young at the time, who went to the mailbox expecting to find bills and flyers and instead found a gumball in a clear envelope. The gumballs came in red, yellow, green, blue. Some kids tried to collect them all, lining them up like trophies, eating them all at once, then, through all that gum, pontificating on the mysteries of taste. By introducing aspartame in a gumball, Searle was not presenting itself as the lesser of evils. The people who eat gumballs are not, after all, the same people who count calories. Searle was taking on sugar itself.

In 1984, Searle made deals with Coca-Cola and Pepsi and many other companies that sold diet foods. These companies would be sold NutraSweet at a tremendous discount. In exchange, they would carry the NutraSweet trademark (a red-and-white swirl) on their labels. The swirl became part of the Diet Coke can. Aspartame, long troubled by its bad reputation, remade itself in the trusted image of Coke and Pepsi. In December 1984, Robert Shapiro, then president of the NutraSweet Group, told The New York Times, "Sugar is in trouble. The industry will have to adjust to that reality. They can't do anything to improve the product."

By the time NutraSweet was introduced as a sweetener, the ground had been well prepared. The mothers had been targeted. The kids who ride backward through the supermarkets and make all the decisions had been brainwashed. It was called Equal. It carried the swirl. It was sold in a light-blue packet because white is nothing and pink is for girls but blue is rational, blue you remember, blue stands out, blue is progress, blue is ocean, blue is sky. Nothing was accidental. Unlike Sweet'N Low, Equal was marketed not as a "sugar substitute" but as an "alternative sweetener." Executives at Searle had determined that, when attached to a food, the word "substitute" (why were they the first to realize this?) is like poison. Also, as sugar is among the most beloved products of the earth, consumers are skeptical of vainglorious efforts to create a facsimile. With "sugar substitute," you get people who want to be thin and don't care how. With "alternative sweetener," you get everyone.

In 1985, Equal outsold Sweet'N Low. NutraSweet had become the No. 1 brand in America. Aspartame sweetened the majority of all diet drinks. Searle reported annual sales of $ 132 million. Cumberland's were half that, around $67 million. Sweet'N Low had been pushed out of the top spot it had occupied since the early 1970s. By the end of the year, Searle and its NutraSweet subsidiary had been sold to the agro-giant Monsanto for an astounding $2.7 billion. (In 2000, Monsanto sold its NutraSweet business and now Merisant manufactures the tabletop sweetener.)

Sweet'N Low, the industry leader for decades, eventually dropped to a distant third behind Equal and Splenda, an artificial tabletop sweetener (it comes in a yellow packet) introduced by Johnson & Johnson in 2000. Yet, amazingly, Cumberland has made almost twice as much money annually in recent years as it did 30 years ago, when Sweet'N Low was the top brand. By bringing artificial sweeteners into the mainstream—many people drink Diet Coke not because they are on a diet but because they prefer the taste—Monsanto supersized the market. In 2004, U.S. manufacturers of artificial sweeteners generated sales of $343 million (compared with $911 million of "real" sugar), of which Cumberland products represented 19.4 percent, or about $66.5 million. "Equal opened up the market," Marvin told me. "And though our share went down, the market got much bigger. Let's say, for example, someone that would never use saccharin decides, because he is bombarded by their sales pitch, to try Equal. He tastes it and says, 'Well, it's O.K.' Then he goes to a restaurant and they only have Sweet'N Low, so he says, 'O.K., I'll try it.' And it tastes even sweeter. So he begins to buy Sweet'N Low."

The artificial-sweetener market is currently dominated by Splenda, the only product I've talked about not discovered by accident. Splenda is part of the scary effort to get into the toy box and tinker with the grains and spices of the earth. We are in the age of the genome and the genetic code, the double helix twisting toward the sun. The age of the accidental discovery is over. Known in the lab as sucralose, Splenda is the result of a holy-grail-like search for a sugar that behaves like saccharin, that leaves no trace in the gut, ass, or hips. It was discovered in 1976 when a scientist at the British sugar company Tate & Lyle re-arranged a sugar molecule, replacing its three hydrogen-oxygen molecules with three chlorine atoms, resulting in a compound that is something like a mirror image of sugar; it looks and tastes like the real thing, yet, because it's so strange, goes unrecognized by the body. It slips right past the turnoffs and checkpoints on its way to the toilet. As if it had never been there. As if that Weight Watchers cake never existed. Splenda is not just another sweetener. It is sugar remade, a molecule stolen from God, put up on blocks, painted, and thrown back on the market.

In 1998, sucralose was introduced in diet foods and soft drinks. Within two years of its release, Splenda had passed Sweet'N Low as the No.-2-selling brand. By the summer of 2003, Splenda had passed Equal. By the winter of 2004, Splenda had reached $ 173 million in annual sales. According to Information Resources, a market-research group in Chicago, Splenda then had 51 percent of the market, Equal 19 percent, and Sweet'N Low 15 percent.

In the beginning, sugar was valued because it offered a treasure of calories and energy in a small dose. Sugar accordingly fueled the growth of the modern city, the modern workforce, and the modern nation. It powered the slave trade and made possible the rise of the mercantile class that overthrew the kings. It fueled the revolutions that gave birth to modern democracies and modern wars. The spread of sugar led to the plagues of obesity and diabetes and tooth decay that generated a need for alternative sweeteners realized with saccharin and cyclamate and aspartame, which, by their success and the resulting health problems, created a need for a new kind of sugar. As NutraSweet's Robert Shapiro said, "Sugar is in trouble. They can't do anything to improve the product." But that's exactly what happened. By scrambling molecules, the scientists replaced an ancient food, valued because a little gives you a lot, with a designer spice, valued because a lot gives you nothing—no calories, no energy. A wooden nickel, a check on an overdrawn account. An old friend returned to us lobotomized, a big fat zero, millions spent to unmake sugar, or remake it with no value. It's the story of the age. Taste without content. Food without value. By the late 1990s, sugar had lost 70 percent of its market to high-fructose corn syrup, saccharin, aspartame, and sucralose. With the invention of sucralose, the story of sugar comes to an end.

Excerpted from Sweet and Low: A Family Story, by Rich Cohen, to be published in April 2006 by Farrar, Straus and Giroux; © 2006 by the author.