Cyclamate: The Sweetener That Was Banned for 55 Years (And Probably Shouldn't Have Been)

Imagine discovering something sweet by accident when you pick up a cigarette during a lab break. That's precisely what happened in 1937 when graduate student Michael Sveda at the University of Illinois stumbled upon cyclamate, an artificial sweetener that would eventually be worth $1 billion annually, become America's most popular diet drink ingredient, and then get banned from the United States in a controversy involving bulldozers crushing soda cans, sugar industry politics, and questionable science.

Cyclamate remains banned in the United States today, over 55 years after the ban. But here's the twist: it's approved and used safely in over 130 countries around the world. Canada uses it. Most of Europe uses it. Australia uses it. But not America.

So what's the real story? Was cyclamate actually dangerous, or was the ban based on flawed science and industry pressure? And why hasn't it been unbanned despite decades of evidence suggesting it's perfectly safe?

This is a story about accidental discovery, corporate competition, media panic, and how one questionable study can change history.

The Accidental Discovery

In 1937, Michael Sveda was a graduate student at the University of Illinois working on synthesizing an antipyretic drug (a fever-reducing medicine). During his work, he put his cigarette down on the lab bench. When he picked it back up and put it in his mouth, he noticed something weird: it tasted sweet.

That sweetness wasn't from the tobacco. It was from whatever chemical compound had gotten on the cigarette from the lab bench. Sveda later said, "God looks after damn fools, children and chemists." The question is whether God also looks after sweeteners.

Sveda had accidentally discovered cyclamate, specifically sodium cyclamate, which would turn out to be about 30 times sweeter than regular sugar. That might not sound super impressive compared to modern artificial sweeteners like aspartame is about 200 times sweeter than sugar, but it had some major advantages: no bitter aftertaste, stable when heated, and cheap to produce.

DuPont purchased the patent for cyclamate and later sold to Abbott Laboratories, which conducted the necessary studies and submitted a New Drug Application in 1950. Abbott initially intended to use cyclamate to mask the bitterness of certain drugs like antibiotics and medications.

But they quickly realized cyclamate had way bigger potential than just making medicine taste better.

The Rise of Diet Everything

In 1958, cyclamate was designated GRAS (generally recognized as safe) by the United States Food and Drug Administration. This was a big deal. GRAS status meant cyclamate could be used in food and beverages without extensive additional testing.

Cyclamate was marketed in tablet form for use by diabetics as an alternative tabletop sweetener, as well as in a liquid form. Because cyclamate is stable to heat, it was marketed as suitable for use in cooking and baking. But the real explosion came with diet soft drinks.

In the 1960s, Americans were becoming increasingly weight-conscious. The diet industry was booming. And cyclamate was the perfect ingredient for creating low-calorie versions of popular foods and drinks. Diet soft drink producers used more than half the cyclamates produced in the United States and, according to BusinessWeek, collectively manufactured products worth $420 million at retail prices in 1969. Of all soft drinks sold in 1969, 15 percent were diet drinks.

Think about that. In just over a decade, cyclamate had gone from a laboratory accident to a billion-dollar industry. Brand names like Diet Pepsi, Tab, Fresca, and Diet-Rite all contained cyclamate. Sweet'N Low packets contained cyclamate. It was everywhere.

By 1969, annual sales of cyclamate had reached $1 billion. But success brought attention. And attention brought scrutiny.

The Study That Changed Everything

Throughout the 1960s, various studies examined cyclamate's safety. In December 1968, a government advisory panel reported to the FDA that no research warranted a reduction from the current recommended consumption limit of 5 grams (the equivalent of more than three quarts of artificially sweetened beverages) of cyclamates per day.

But then came 1969.

Early studies linked the combination of cyclamate plus saccharin (and, to a lesser extent, cyclamate alone) with the development of bladder cancer in laboratory animals, particularly male rats. Here's what the study did: researchers fed rats massive doses of cyclamate mixed with saccharin (another artificial sweetener) in a 10:1 ratio. We're talking amounts equivalent to a human drinking hundreds of cans of diet soda every single day for their entire life.

Some of the rats developed bladder tumors; the media went absolutely wild. The New York Times showed pictures of concerned housewives standing next to large displays of diet drinks. Newsweek published a photograph of a bulldozer in Toronto crushing thousands of cans of Canada Dry. The image of bulldozers destroying soda became the symbol of the cyclamate scare. It was dramatic. It was frightening. And it sold newspapers.

The Ban

In October 1969, Department of Health, Education & Welfare Secretary Robert Finch, bypassing Food and Drug Administration Commissioner Herbert L. Ley, Jr., removed the GRAS designation from cyclamate and banned its use in general-purpose foods, though it remained available for restricted use in dietary products with additional labeling.

Then, in October 1970, the FDA, under a new commissioner, banned cyclamate altogether from all food and drug products in the United States.

The Pepsi-Cola company scored a coup by having a new diet drink formulation on the market almost as soon as the ban was instituted. In fact, the company ran advertisements the day after the ban was announced, showing the Diet Pepsi product boldly proclaiming "Sugar added! No Cyclamates!" with the byline "Pepsi-Cola Company cannot in good conscience offer its customers any product about which even the remotest doubt exists."

Pepsi basically used the ban as a marketing opportunity. They'd already been working on cyclamate-free formulations and positioned themselves as the responsible choice.

The Controversy

Michael Sveda, the discoverer of cyclamate, was furious about the ban. He accused the FDA of "a massive cover-up of elemental blunders" and claimed that the original ban was based on sugar politics and bad science.

And he had a point.

The study that triggered the ban had serious problems:

Ridiculous Doses: The rats were given amounts of cyclamate that no human could ever consume. It would be like drinking 350 cans of diet soda every day for your entire life.

Mixed with Saccharin: The rats weren't given pure cyclamate. They were given a cyclamate-saccharin mixture. So was it the cyclamate causing tumors? The saccharin? The combination? Nobody knew for sure.

Bad Study Design: Doubt was cast on the results of the independent study linking sweetener use to tumors in rats, because the study was not designed to evaluate cancer risks but to develop long-term toxicity data.

Abbott Laboratories claimed that its own studies were unable to reproduce the 1969 study's results.

And then there's this: In 2000, a paper was published describing the results of a 24-year-long experiment in which 16 monkeys were fed a normal diet and 21 monkeys were fed either 100 or 500 mg/kg cyclamate per day; the higher dose corresponds to about 30 cans of a diet beverage. Two of the high-dosed monkeys and one of the lower-dosed monkeys were found to have malignant cancer, each with a different kind of cancer, and three benign tumors were found. The authors concluded that the study failed to demonstrate that cyclamate was carcinogenic because the cancers were all different, occurred at the same frequency as expected in healthy monkeys, and there was no way to link cyclamate to each of them.

Translation: Even when monkeys drank the equivalent of 30 diet sodas a day for 24 years, they didn't get cancer at rates higher than normal.

The Fight to Unban It

In 1973, Abbott petitioned the FDA to lift the ban on cyclamate. This petition was eventually denied in 1980 by FDA Commissioner Jere Goyan despite the science kept piling up in cyclamate's favor. In 1984, the Cancer Assessment Committee of the U.S. Food and Drug Administration (FDA) concluded that cyclamate is not carcinogenic.

Let us repeat that: The FDA's own cancer committee said cyclamate doesn't cause cancer.

In 1982, the FDA was sufficiently concerned over the validity of the data that promoted the ban originally that it instituted a yearlong study by the National Academy of Sciences. The report issued by this group concluded that cyclamate itself does not cause cancer but raised issues that left the safety of the sweetener in dispute. The committee stated that there was "suggestive evidence" that cyclamate was a tumor promoter, or cocarcinogen.

So cyclamate doesn't cause cancer by itself, but maybe it helps other things cause cancer? The evidence was vague and suggestive, not definitive. Despite all this, cyclamate remains banned in the United States. A petition shared by the Calorie Control Council and Abbott Laboratories for the reapproval of cyclamate in the United States has been submitted to the FDA. But as of 2025, nothing has changed.

Meanwhile, in the Rest of the World...

Here's the really wild part: Cyclamate is approved as a sweetener in at least 130 countries.

Sweeteners produced by Sweet'n Low and Sugar Twin for Canada contain cyclamate, though not those produced for the United States. Same brand names. Different formulations depending on which side of the border you're on.

In the Philippines, cyclamate was banned until the Philippine Food and Drug Administration lifted the ban in 2013, declaring it safe for consumption.

The European Union allows it. Australia allows it. New Zealand allows it. Dozens of countries around the world have looked at the science and decided cyclamate is safe for human consumption.

But not the United States.

So Why Is It Still Banned?

If the science says cyclamate is safe, and over 130 countries allow it, why does the United States still ban it?

There are a few theories:

Political Inertia: Unbanning something requires political will. It's easier to leave things as they are than to reopen a decades-old controversy.

Industry Competition: By the time cyclamate could have been unbanned, other sweeteners (saccharin, aspartame, sucralose) had taken over the market. Companies making those products have no incentive to support reintroducing a competitor.

Public Perception: The cyclamate ban is part of public memory. "That sweetener they banned because it causes cancer" is hard to shake, even if the science doesn't support it.

The Precautionary Principle: Some argue that even if cyclamate probably doesn't cause cancer, the "suggestive evidence" is enough to keep it banned. Why take any risk, however small?

Sugar Industry Lobbying: Michael Sveda certainly thought sugar industry lobbyists were behind the original ban, trying to protect their market from artificial sweeteners. Whether that's true or a conspiracy theory is debatable, but the sugar industry definitely benefited from cyclamate's removal.

What We've Learned

The cyclamate story teaches us several important lessons:

Science Communication Matters: The way the 1969 study was reported created panic. "Artificial sweetener causes cancer in rats" makes for scary headlines, but "rats given impossibly high doses of sweetener-saccharin mixture develop tumors" is more accurate and less alarming.

Bad Studies Can Have Long-Term Consequences: One flawed study in 1969 led to a ban that's lasted over 55 years, despite dozens of subsequent studies showing cyclamate is safe.

Policy Is Harder to Change Than Science: Scientific consensus can shift, but government policy often lags behind. Once something is banned, unbanning it requires overcoming political, economic, and public perception hurdles.

Follow the Money: Whether it's the sugar industry, competing artificial sweetener manufacturers, or diet drink companies, financial interests play a huge role in what gets approved and what stays banned.

The Irony

Here's the biggest irony: Cyclamate is often used with other artificial sweeteners, especially saccharin; the mixture of 10 parts cyclamate to 1 part saccharin is common and masks the off-tastes of both sweeteners.

Remember, the study that got cyclamate banned used a cyclamate-saccharin mixture. Saccharin was also briefly considered for a ban but ultimately wasn't banned in the United States. So the sweetener that was mixed with cyclamate in the study that caused the panic is still legal, while cyclamate is not.

It doesn't make a lot of sense.

Where We Are Now

Today, if you want to use cyclamate in the United States, you can't. Cyclamate remains banned in the United States, South Korea, and Bangladesh. If you cross into Canada, you can buy Sweet'N Low with cyclamate in it. If you travel to Europe, you'll find cyclamate in diet products. If you visit Australia, same thing.

The science says it's safe. Over 130 countries agree. But the United States, where cyclamate was discovered, where it became a billion-dollar industry, where it was consumed by millions of people for over a decade, still won't allow it.

Michael Sveda passed away in 1999, never seeing his discovery unbanned in his home country. He spent decades arguing that the ban was based on bad science and industry politics. Whether he was right or not, one thing is clear: the cyclamate ban is one of the strangest regulatory decisions in modern food history.

And it shows how hard it is to undo a decision once it's been made, even when the science changes.

Sources

1. EBSCO Research - "Artificial Sweetener Cyclamate Is Introduced" - Media coverage of ban, Michael Sveda's response, and National Academy of Sciences study

2. EBSCO Research - "Artificial Sweetener Cyclamate Is Banned from U.S. Consumer Markets" - Market statistics, consumption recommendations, and diet drink industry impact

3. Wikipedia - "Cyclamate" - Discovery by Michael Sveda, patent history, GRAS designation, ban timeline, monkey study results, international approval status

4. ScienceDirect Topics - "Sodium Cyclamate" - Chemical properties and regulatory status

5. Cyclamate.org - "Safety of cyclamate as sugar substitute" - FDA Cancer Assessment Committee conclusion and reapproval petition

6. Bayn Solutions - "Cyclamates – a guide to artificial sweeteners" - Discovery story and Dr. Sveda's quote

7. Rutgers University - "FDA's Persistent Ban on the Artificial Sweetener Cyclamate" - Ban persistence despite lack of evidence

8. Wikipedia - "Sugar substitute" - Comparative information on artificial sweeteners

9. National Cancer Institute - "Artificial Sweeteners and Cancer" - Studies linking cyclamate-saccharin combination to bladder cancer in rats

10. WikiSummaries - "Artificial Sweetener Cyclamate Is Banned from U.S. Consumer Markets" - Consumption statistics and brand names containing cyclamate