It’s Really Hard to Study Artificial Sweeteners

The health effects of saccharin, aspartame, and sucralose can be nearly impossible to tease apart from the impact of everything else people eat alongside them.

A hand pouring out a packet of Splenda
Winslow Townson / AP

For decades, ads for treats sweetened with substances like Sweet’N Low, NutraSweet, and Splenda have promised what seems like a miracle of modern science: that you can enjoy all the dessert you want, calorie-free. No need to deprive yourself—with artificial sweeteners, you can literally have your cake and eat it, too. But are these substances safe? Don’t they cause cancer in rats and mess up your metabolism? Listen in now for answers to all these questions, plus the tale of a sugar-free gumball marketing blitz, courtesy of none other than Donald Rumsfeld.

More than a century ago, a chemist named Constantin Fahlberg was hard at work in a lab at Johns Hopkins University, trying to develop a new food preservative from coal tar. “He apparently licked his finger by accident, and noticed that it was sweet,” says Carolyn Thomas, author of Empty Pleasures: The Story of Artificial Sweeteners From Saccharin to Splenda. One gram of Fahlberg’s new substance was 500 times sweeter than a gram of sugar, so he gave this “perfectly harmless spice” the name saccharin, from the adjective saccharine, meaning “overly sweet.”

A small company by the name of Monsanto quickly brought saccharin to market, and companies started adding it to soda as a cheap substitute for sugar. “Consumers were actually tasting it before they even knew what it was,” Thomas explains. At the time, sugar was perceived as a health food, full of useful calories—and so when people eventually found out that their soda was “adulterated” with saccharin instead of sugar, they revolted, and saccharin was nearly banned. It took a presidential pardon to save it: Teddy Roosevelt, a diabetic, intervened to make sure saccharin remained on the shelves, albeit as medicine rather than food.

In this episode, with Thomas’s help, we trace saccharin’s rise from a small white pill reserved for diabetics, to a dainty treat for women, to the magic trick underlying postwar American abundance and diet culture. Today, saccharin is just one of many artificial sweeteners found in processed food throughout the grocery store, each of which offers slightly different flavor notes and chemical properties that make them best suited to sugar-free gum, or yogurt, or diet soda. Indeed, these sugar alternatives are now so ubiquitous that scientists who study their effects say that it’s hard to find people who haven’t consumed them.

Nonetheless, doubts still linger about their safety. Does saccharin cause cancer? Will aspartame lead to weight gain? Is sucralose messing with your metabolism? To answer these questions, we speak with Richard Mattes, who studies artificial sweeteners at Purdue University; Vasanti Malik, a researcher at Harvard; Barry Popkin, a nutrition professor at the University of North Carolina; and Eran Elinav, who studies the microbiome at the Weizmann Institute in Israel. Together, they help us tease out the very best and most up-to-date science on whether these substances cause not just cancer but also heart attacks and strokes—as well as whether they can actually help people lose weight. Listen in now for the surprising conclusion; in the end, it seems that artificial sweeteners’ true dangers are not necessarily the ones we worry about.

This post appears courtesy of  Gastropod.