Scientists Turn Bacteria Into Sugar Factories

Scientists just figured out how to make tiny bacteria produce a sugar that tastes sweet, bakes beautifully, and contains far fewer calories than what's in your pantry right now.

Researchers at Tufts University engineered common bacteria to act as microscopic factories, churning out tagatose, a rare sugar that occurs naturally in small amounts in fruits and dairy. The sweetener delivers 92% of the sweetness of regular sugar with roughly 60% fewer calories and barely raises blood sugar levels.

"We developed a way to produce tagatose by engineering the bacteria Escherichia coli to work as tiny factories, loaded with the right enzymes to process abundant amounts of glucose into tagatose," said Nikhil Nair, associate professor of chemical and biological engineering at Tufts. The team published their findings in Cell Reports Physical Science in December.

What makes this breakthrough exciting is that tagatose actually behaves like sugar when you cook with it. It browns when heated and creates similar flavors and textures in baked goods, something most sugar substitutes struggle to replicate.

Previous methods to produce tagatose existed but were expensive and inefficient, making the sweetener too costly for widespread use. The 2019 version of this process used galactose, a pricier sugar that's harder to find.

The latest advance came from discovering a new enzyme that lets the bacteria use glucose instead, which is abundant and affordable. This simple swap could eventually make tagatose accessible enough to appear in everyday food products.

The health benefits look promising. Clinical studies show tagatose raises blood glucose and insulin much less than conventional sugar, making it potentially helpful for people with diabetes or those trying to limit sugar intake. The FDA has classified it as "generally recognized as safe."

Like other low-calorie sugars, tagatose may cause mild digestive discomfort in some people at higher doses because it's not fully absorbed in the small intestine. Some studies suggest it doesn't promote tooth decay the way regular sugar does and may influence gut bacteria positively because it ferments in the colon.

The Bright Side

The final product would be purified and chemically identical to tagatose from natural sources, containing none of the bacteria used in manufacturing. Registered dietitian Lakelyn Lumpkin from Top Nutrition Coaching notes that while replacing some added sugars with alternatives like tagatose could help reduce caloric intake, overall dietary patterns still matter most.

Researchers emphasize that significant optimization for productivity, scale-up, and purification is needed before widespread manufacturing can begin, but the pathway forward looks clearer than ever.

This breakthrough turns an abundant resource into a healthier option that doesn't ask people to sacrifice the joy of baking or the comfort of sweetness.