Weight Loss Breakthrough: Scientists Develop Edible “Fat Sponges” From Green Tea and Seaweed

Researchers have developed plant-based microbeads that block fat absorption in the gut.

Current strategies for weight loss, such as gastric bypass surgery or medications that block fat absorption, often come with significant risks or unpleasant side effects. Scientists are now exploring a different option: edible microbeads made from green tea polyphenols, vitamin E, and seaweed. Once swallowed, these beads attach to dietary fats inside the digestive tract. Early studies in rats that were fed high-fat diets suggest this method could provide a safer and more widely available alternative to traditional surgery or drug-based treatments.

Yue Wu, a graduate student at Sichuan University, is scheduled to present the team’s findings at the ACS Fall 2025 Digital Meeting.

“Losing weight can help some people prevent long-term health issues like diabetes and heart disease,” says Wu. “Our microbeads work directly in the gut to block fat absorption in a noninvasive and gentle way.”

The Challenge of Fat Absorption

Weight gain can be influenced by both genetic and lifestyle factors, one of the most important being diet. According to the U.S. Department of Agriculture, a high-fat diet is defined as one in which 35% or more of daily calories come from fat rather than protein or carbohydrates.

Some approved drugs, such as orlistat, reduce fat absorption by interfering with the enzymes that break down dietary fats. While effective, orlistat has been linked to serious side effects in certain patients, including damage to the liver and kidneys.

So, Wu and her colleagues wanted to target the fat absorption process with their weight-loss intervention but do so without negative side effects. “We want to develop something that works with how people normally eat and live,” says Wu.

To get started, the team created tiny plant-based beads that spontaneously form through a series of chemical bonds between the green tea polyphenols and vitamin E. These structures can form chemical tethers to fat droplets and serve as the fat-binding core of the microbeads. The researchers then coated the spheres in a natural polymer derived from seaweed to protect them from the acidic environment of the stomach. Once ingested, the protective polymer coating expands in response to the acidic pH, and the green tea polyphenols and vitamin E compounds bind to and trap partially digested fats in the intestine.

Integrating Microbeads into Diets

The microbeads are nearly flavorless, and the researchers foresee them being easily integrated into people’s diets. For example, the microbeads could be made into small tapioca- or boba-sized balls and added to desserts and bubble teas.

The researchers assessed the microbeads as a weight-loss treatment in rats. They put the animals into three groups (eight rats per group), those which were fed a high-fat diet (60% fats) either with or without microbeads and those which were fed a normal diet (10% fats) for 30 days. Rats fed the high-fat diet and microbeads:

• Lost 17% of their total body weight, while rats in the other groups didn’t lose weight.
• Had reduced adipose tissue and less liver damage compared to rats fed the high-fat and normal diets without microbeads.
• Excreted more fat in their feces compared to rats not given microbeads. The extra fat in the rats’ feces had no apparent ill effects on the animals’ health.

Additionally, the eight rats on high-fat diets that consumed microbeads showed similar intestinal fat excretion, but without the gastrointestinal side effects the researchers observed with a fourth group of rats they treated with orlistat.

Wu and her team have started working with a biotechnology company to manufacture the plant-based beads. “All the ingredients are food grade and FDA-approved, and their production can be easily scaled up,” says Yunxiang He, Sichuan University associate professor and co-author on Wu’s presentation.

They’ve also initiated a human clinical trial in collaboration with the West China Hospital of Sichuan University. “This represents a major step toward clinical translation of our polyphenol-based microbeads, following our foundational results,” says Wu. “We have officially enrolled 26 participants in our investigator-initiated trial, and we anticipate that preliminary data may become available within the next year.”

Meeting: ACS Fall 2025

The research was funded by National Key R&D Program of China; the National Excellent Young Scientists Fund; the National Natural Science Foundation of China; the Talents Program of Sichuan Province; the Double First-Class University Plan of Sichuan University; the State Key Laboratory of Polymer Materials Engineering; the Tianfu Emei Program of Sichuan Province; the Postdoctoral Special Funding of Sichuan Province; the Postdoctoral Funding of Sichuan University; the Ministry of Education Key Laboratory of Leather Chemistry and Engineering; and the National Engineering Research Center of Clean Technology in Leather Industry.

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