The analysis focused on three drugs classified as GLP-1 receptor antagonists. Across the board, each medication produced greater weight loss than a placebo. At the same time, researchers found gaps in the evidence, especially regarding long-term health outcomes, side effects, and possible conflicts of interest tied to industry funding.

From Diabetes Treatment to Obesity Therapy

Glucagon-like peptide-1 (GLP-1) receptor agonists were first developed to treat type 2 diabetes and began clinical use in the mid-2000s. In people with diabetes, particularly those with heart or kidney disease, these medications improved blood sugar levels, lowered the risk of heart and kidney complications, supported weight reduction, and reduced the risk of early death.

In recent years, researchers have tested GLP-1 receptor agonists in people with obesity. These drugs copy the action of a naturally occurring hormone that slows digestion and increases feelings of fullness. In the United Kingdom, they are approved for weight management when combined with a reduced calorie diet and exercise in individuals with obesity, or in those who are overweight and have weight-related health conditions.

How Much Weight Loss Do GLP-1 Drugs Produce

Across the three reviews, tirzepatide (Mounjaro and Zepbound), semaglutide (Ozempic, Wegovy, and Rybelsus), and liraglutide (Victoza and Saxenda) all led to notable weight loss over one to two years compared with placebo. The benefits appear likely to continue as long as patients remain on treatment.

• Tirzepatide (administered once weekly) led to an average weight reduction of about 16% after 12 to 18 months. Data from 8 randomized controlled trials (6,361 participants) indicated that this level of weight loss could last as long as 3.5 years, although information on long-term safety remains limited.
• Semaglutide (also injected weekly) produced an average weight loss of roughly 11% after 24 to 68 weeks. Findings from 18 randomized controlled trials (27,949 participants) suggest the effect can persist for up to two years. Participants taking semaglutide were more likely to lose at least 5% of their body weight, but they also experienced higher rates of mild-to-moderate gastrointestinal side effects.
• Liraglutide (a daily injection) showed more modest results, with average weight loss of about 4-5% based on 24 trials (9 937 participants). Even so, more people achieved meaningful weight loss compared with placebo. Evidence beyond two years of treatment was limited.

When it came to major cardiovascular events, quality of life, or death, researchers found little or no difference between the GLP-1 drugs and placebo. Side effects were more common with the medications, particularly nausea and other digestive issues, and some participants discontinued treatment as a result.

“These drugs have the potential to bring about substantial weight loss, particularly in the first year,” says Juan Franco, co-lead researcher from Heinrich Heine University Düsseldorf, Germany. “It’s an exciting moment after decades of unsuccessful attempts to find effective treatments for people living with obesity.”

Concerns About Industry Funding and Access

A large share of the studies included in the reviews were funded by the companies that manufacture the drugs. In many cases, the companies were deeply involved in designing, conducting, analyzing, and reporting the trials. This level of involvement raises concerns about potential conflicts of interest and underscores the need for more independent research.

The authors also stress that broader use of GLP-1 medications must account for social and commercial determinants of health, such as cost, insurance coverage, and overall access. Without careful planning, expanded use could worsen existing health disparities among people living with obesity. High prices currently restrict access to semaglutide and tirzepatide, while liraglutide has become more affordable after its patent expired, allowing generic versions to enter the market. Semaglutide’s patent will also expire in 2026.

Most of the trials reviewed were conducted in middle- and high-income countries. Regions including Africa, Central America, and Southeast Asia were underrepresented or not represented at all. Because body composition, diet, and health behaviors vary widely across populations, researchers emphasize the importance of studying how these drugs perform in diverse global settings.

“We need more data on the long-term effects and other outcomes related to cardiovascular health, particularly in lower-risk individuals,” says Eva Madrid, co-lead researcher from the Universidad de Valparaíso, Chile. “Weight regain after stopping treatment may affect the long-term sustainability of the observed benefits. More independent studies from a public health perspective are needed.”

Long-Term Evidence Needed for Future Guidelines

The reviews conclude that longer-term, independently funded studies are crucial for guiding both medical practice and public health policy. A clearer understanding of sustained benefits and risks will help define the role of GLP-1 receptor agonists in long-term weight management.

Commissioned by the World Health Organization, these findings will inform new WHO guidelines on the use of GLP-1 receptor agonists for obesity treatment.

Their work, published in ChemSystemsChem, offers a fresh way to think about the origin of life on our planet and even raises new possibilities for finding life elsewhere in the universe.

For centuries, people have wondered how life first emerged. Although no one can observe those earliest moments directly, researchers continue to reconstruct what might have happened using clues from chemistry, physics, and geology.

“While many theories focus on the function of biomolecules and biopolymers, our theory instead incorporates the role of gels at the origins of life,” said Tony Z. Jia, professor at Hiroshima University and co-lead author of the paper.

The Prebiotic Gel-First Hypothesis

The researchers propose what they call a “prebiotic gel-first” framework. In this scenario, life’s earliest steps took place inside surface-attached gel matrices, which are sticky, semi-solid materials similar in some ways to modern microbial biofilms. Biofilms are the thin layers of bacteria that commonly grow on rocks, pond surfaces, and even human-made structures.

Using concepts from soft matter chemistry and insights from modern biology, the team suggests that these primitive gels could have created the right physical setting for simple chemical systems to grow more complex, well before the first cells formed.

These gels may have helped solve major challenges faced by early chemistry. By trapping and organizing molecules, they could have increased molecular concentration, held onto useful compounds, and shielded delicate reactions from environmental changes. Within such protected spaces, early chemical networks might have developed proto-metabolic activity and even basic self-replication, laying important groundwork for biological evolution.

“This is just one theory among many in the vast landscape of origin-of-life research,” said Kuhan Chandru, research scientist at the Space Science Center, National University of Malaysia (UKM) and co-lead author of the study. “However, since the role of gels has been largely overlooked, we wanted to synthesize scattered studies into a cohesive narrative that puts primitive gels at the forefront of the discussion.”

Implications for Alien Life and Astrobiology

The idea does not stop with Earth. The researchers suggest that comparable gel-like systems might exist on other planets. These hypothetical structures, described as “Xeno-films,” could function like biofilms but be built from entirely different chemical ingredients available in other environments.

This shift in thinking could expand how scientists search for extraterrestrial life. Instead of focusing only on familiar biological molecules, future missions might also look for organized, gel-like structures that create life-friendly environments.

Testing the Gel Model

The team plans to test their hypothesis in the lab. They intend to examine how simple chemicals under early Earth conditions might have formed gels and to study what properties those gels could have offered emerging chemical systems.

“We also hope that our work inspires others in the field to further explore this and other underexplored origins-of-life theories!” said Ramona Khanum, co-first author of the paper and a former intern at UKM.

The University of Leeds Research Mobility Funding, the Alexander von Humboldt Foundation, the Japan Society for the Promotion of Science, and the Mizuho Foundation for the Promotion of Science supported this research.

This summer, that traveler entered our solar system and received the name 3I/ATLAS, becoming only the third confirmed interstellar comet ever observed. When researchers at Auburn University aimed NASA’s Neil Gehrels Swift Observatory at the object, they uncovered something extraordinary: the first detection of hydroxyl (OH) gas coming from it, a clear chemical sign of water. Swift was able to detect a faint ultraviolet glow that ground based telescopes cannot see because it operates above Earth’s atmosphere, where this type of light is not blocked before reaching the surface.

First Detection of Water on Interstellar Comet 3I/ATLAS

Identifying water through its ultraviolet byproduct, hydroxyl, marks an important step in understanding how interstellar comets behave and change over time. In comets that formed within our own solar system, water serves as the primary measure of activity. Scientists use it to determine how sunlight triggers the release of other gases and to compare the mix of frozen materials inside a comet’s nucleus. Detecting the same water signature in 3I/ATLAS means astronomers can now evaluate it using the same standards applied to familiar solar system comets. That comparison opens the door to studying how planetary systems across the galaxy may differ or resemble our own.

Unexpected Water Activity Far From the Sun

What makes 3I/ATLAS especially intriguing is the distance at which this water activity was observed. Swift detected hydroxyl when the comet was nearly three times farther from the Sun than Earth is, well beyond the region where surface ice would normally turn directly into vapor. Even at that distance, the comet was losing water at a rate of about 40 kilograms per second, comparable to water blasting from a fully opened fire hose. Most comets native to our solar system remain relatively inactive that far out.

The strong ultraviolet signal suggests that additional processes may be involved. One possibility is that sunlight is warming tiny icy particles that have broken away from the nucleus. As those grains heat up, they could release vapor and supply the surrounding cloud of gas. Only a small number of distant comets have shown this kind of extended water source, and it points to layered ices that may preserve information about how and where the object originally formed.

Clues to Planet Formation Beyond Our Solar System

Each interstellar comet discovered so far has revealed something different about chemistry in other planetary systems. Together, these visitors show that the ingredients that build comets, especially volatile ices, can vary widely from one star system to another. Those differences provide insight into how temperature, radiation, and chemical makeup shape the materials that eventually form planets and possibly create conditions suitable for life.

How NASA’s Swift Observatory Made the Discovery

Detecting that faint ultraviolet signal was also a technical achievement. NASA’s Neil Gehrels Swift Observatory carries a relatively small 30 centimeter telescope, yet from its position in orbit it can observe ultraviolet wavelengths that are mostly absorbed by Earth’s atmosphere. Without interference from air and sky brightness, Swift’s Ultraviolet/Optical Telescope can reach a sensitivity comparable to a 4 meter class ground telescope at those wavelengths. Its ability to respond quickly allowed the Auburn team to observe 3I/ATLAS within weeks of its discovery, before it became too faint or moved too close to the Sun for safe observation from space.

“When we detect water — or even its faint ultraviolet echo, OH — from an interstellar comet, we’re reading a note from another planetary system,” said Dennis Bodewits, professor of physics at Auburn. “It tells us that the ingredients for life’s chemistry are not unique to our own.”

“Every interstellar comet so far has been a surprise,” added Zexi Xing, postdoctoral researcher and lead author of the study. “‘Oumuamua was dry, Borisov was rich in carbon monoxide, and now ATLAS is giving up water at a distance where we didn’t expect it. Each one is rewriting what we thought we knew about how planets and comets form around stars.”

3I/ATLAS has since dimmed and is currently out of view, but it is expected to become observable again after mid November. That return will give scientists another opportunity to monitor how its activity changes as it moves closer to the Sun. The detection of hydroxyl, detailed in The Astrophysical Journal Letters, offers the first solid proof that this interstellar comet is releasing water far from the Sun. It also highlights how even a modest space based telescope, operating above Earth’s atmosphere, can capture faint ultraviolet signals that connect this rare visitor to the broader family of comets and to the distant planetary systems where such objects are born.