Scientists found a surprising problem with sugar-free diets

 Giving up sugar entirely may not be as beneficial as many people assume. New research presented Saturday at ENDO 2026, the Endocrine Society's annual meeting in Chicago, suggests that completely removing sugar from the diet could have unintended effects on gut and metabolic health.

Researchers from the Dasman Diabetes Institute in Kuwait examined what happened when mice were fed a low-fat diet that contained no sucrose, a common form of sugar. The study compared those animals with a control group that received a low-fat diet containing sucrose over a 16-week period.

"Completely removing sucrose from a low-fat diet may unexpectedly disrupt gut health and promote inflammation and metabolic dysfunction, highlighting that balanced nutrition is more important than simply eliminating sugar," said Rasheed Ahmad, Ph.D., principal scientist and head of the Immunology & Microbiology Department at the Dasman Diabetes Institute, in Kuwait City, Kuwait. The institute was founded by Kuwait Foundation for the Advancement of Sciences.

Sugar-Free Diet Linked to Metabolic Changes

To evaluate the effects of eliminating sucrose, the researchers measured glucose tolerance, insulin sensitivity, circulating metabolic hormones, the gut microbiome, and inflammation in both the colon and liver.

Despite maintaining similar body weights, mice on the sucrose-free diet experienced several negative health changes compared with the control group. These included poorer glucose control, insulin resistance, imbalances in gut microbes, intestinal inflammation, and changes associated with fatty liver disease.

"The findings suggest that complete removal of sucrose from a low-fat diet may negatively affect gut microbiota and metabolic health," Ahmad said. "The study highlights the importance of maintaining balanced dietary carbohydrates to support gut and immune homeostasis."

Gut Microbiome and Dietary Balance

According to the researchers, little was previously known about the potential consequences of highly restrictive low-fat diets that eliminate sugar entirely.

"This research may influence future dietary recommendations by emphasizing the importance of maintaining a healthy gut microbiome rather than focusing only on sugar restriction," Ahmad said. "In the long term, these findings could help improve strategies for preventing and managing metabolic disorders, fatty liver disease and chronic inflammatory conditions."

The team believes the results underscore the need to consider overall dietary balance, rather than concentrating solely on reducing sugar intake.

"Studies such as this reflect our institute's commitment to advancing evidence-based scientific discoveries that improve public health outcomes and deepen our understanding of metabolic disease," said Faisal Hamed Al-Refaei, MD, Acting Director General of Dasman Diabetes Institute.

Source: ScienceDaily

Millipedes beat vertebrates to land by 80 million years

 For hundreds of millions of years before dinosaurs appeared and long before vertebrates ventured onto land, millipedes were already thriving on Earth's surface.

These humble decomposers played a key role in some of the planet's earliest terrestrial ecosystems. Yet despite their remarkable history, major questions about their evolution remained unanswered.Now, an international team led by Virginia Tech researchers has filled in one of the final gaps in the millipede family tree, shedding new light on the ancient creatures that helped prepare Earth for life on land.

The study, published in Current Biology, presents the first complete evolutionary history of all living millipede orders. By combining DNA data from modern species with physical evidence preserved in fossils, the researchers traced the origins of millipedes back nearly 460 million years, suggesting they existed long before the oldest millipede fossils discovered so far.

"Millipedes beat vertebrates onto land by more than 80 million years," said Paul Marek, the study's lead investigator and associate professor in the College of Agriculture and Life Sciences' Department of Entomology. "They really set the stage for later life on land, including humans and vertebrates."

Solving a Longstanding Millipede Mystery

For more than 100 years, scientists recognized the existence of two rare millipede groups, Siphoniulida and Siphonocryptida. However, because fresh specimens were unavailable for DNA analysis, researchers could not determine exactly where these groups belonged on the millipede family tree.

One group consists of millipedes less than a centimeter long that spend their lives underground. The other survives in only a handful of known locations.

"These last two were kind of like our white whales," Marek said.

To find them, researchers traveled to Los Tuxtlas in Mexico and the Canary Islands of Spain. There they collected Siphoniulus neotropicus and Hirudicryptus canariensis, two species whose DNA had never before been included in an evolutionary study.

"It took 10 people over a week just to find this one tiny 10-millimeter adult," said Luisa "Fernanda" Vasquez-Valverde M.S. '21, Ph.D. '24, the paper's first author and an assistant in Marek's lab. "Finding them in the field was hard because we were just seeing this little white nematode. We didn't know for sure it was a millipede until we looked under the microscope."

The team sequenced DNA from the two groups and compared hundreds of genes across 82 millipede species. They also incorporated evidence from 29 fossils. Together, these data allowed the researchers to determine where the mysterious groups fit within millipede evolution and when their lineages first emerged.

The project produced terabytes of genetic data and relied on Virginia Tech's Advanced Research Computing resources to reconstruct evolutionary relationships stretching back hundreds of millions of years.

The results showed that Siphonocryptida is not a separate millipede order as previously thought, but instead belongs within an existing lineage. Siphoniulida, meanwhile, was finally placed alongside its closest evolutionary relatives.

Millipedes on an Ancient Earth

The analysis indicates that millipedes may have originated nearly 460 million years ago, about 35 million years earlier than the oldest known millipede fossils and significantly earlier than previous estimates suggested.

"The biggest surprise was just how ancient some of these lineages turned out to be," Marek said.

At that time, Earth looked very different from today. According to Marek, millipedes were among the early pioneers of life on land, helping recycle nutrients by feeding on decaying organic material in some of the first terrestrial ecosystems.

"There were no vertebrates, no trees, no leaves, no flowering plants, no plants with seeds," Marek said. "Millipedes were feeding on decaying mosses, decomposed slime, and primordial gunk on the surface of the Earth."

The Origins of Millipede Chemical Defenses

The newly completed evolutionary tree also helped researchers pinpoint when one of the group's most notable adaptations appeared.

"They made the first chemical weapons," Marek said. "They're little chemical factories."

The study suggests these chemical defenses originated about 260 million years ago, offering the clearest evidence yet for when millipedes first evolved this capability.

Source: ScienceDaily

A dying star could create a new universe instead of a black hole

 Massive stars produce light and heat through nuclear fusion, a process that releases enormous amounts of energy from their cores. Eventually, however, the largest stars run out of fuel. Once that happens, the outward pressure generated by radiation is no longer strong enough to resist gravity. The star begins collapsing under its own weight, theoretically continuing until all of its mass is compressed into a single point known as a singularity.

Although black holes are widely accepted by physicists, they still raise profound questions. How can a mass equal to billions of Suns be squeezed into an infinitely small point? How can spacetime become infinitely curved at a singularity?

At this extreme limit, the known laws of physics cease to provide reliable answers. Scientists cannot accurately describe what happens under such conditions. Black holes also present another challenge because they hide everything beyond their event horizons. Any matter, radiation, or information that crosses this boundary, including light itself, can no longer be observed.

Gravastars and the Role of Dark Energy

Because of these unresolved issues, some researchers have explored the possibility that at least some objects identified as black holes could actually be something else entirely. One proposed alternative is an ultra compact object known as a gravastar.

Gravastars would be nearly as dense and massive as black holes, making them extremely difficult to detect because of their intense gravitational pull. Unlike black holes, however, they would not contain a singularity or an event horizon. Instead, beneath their outer layers of ordinary matter, they would be filled with dark energy. This mysterious form of energy produces an outward pressure that counteracts gravity and prevents complete collapse.

For many physicists, gravastars offer an appealing alternative because they avoid some of the conceptual problems associated with black holes. Yet one major question has remained unanswered for decades: How could gravastars actually form?

New Solution Suggests a Mini Universe Forms

Theoretical physicists Daniel Jampolski and Professor Luciano Rezzolla have now proposed what they describe as the first dynamic solution to Albert Einstein's equations of General Relativity that explains how a collapsing star could produce a gravastar.

According to their work, the collapse of a massive star may trigger the birth of a miniature universe within the collapsing matter itself. This newly formed universe would not be very different from the Big Bang that gave rise to our own cosmos. As in our universe, dark energy would drive its expansion.

As the mini universe expands, it pushes outward against the inward pull of gravity. This opposing force can halt the collapse before a black hole forms. The result is a stable balance between the collapsing stellar material and the expanding interior universe. That balance creates a gravastar.

The researchers say their solution provides the first explanation for a question scientists have debated for roughly 25 years: how gravastars could emerge from the collapse of ordinary matter.

Room for New Physics

Daniel Jampolski, who developed the solution during his master's thesis under the supervision of Luciano Rezzolla, explains: "The Big Bang of the emerging universe can unfold once the star has already collapsed almost to the point of becoming a black hole."

The behavior of matter compressed to such extraordinary densities remains poorly understood, leaving open the possibility of new physical phenomena. As Jampolski notes: "It is easier to imagine that the Big Bang occurs only at a very late stage, when matter has already been compressed to an extreme degree, thereby giving rise to new effects."

Rezzolla, Professor of Theoretical Astrophysics at Goethe University, emphasizes that exploring alternatives does not mean rejecting black holes. "Looking for alternatives to black holes should not suggest a skepticism towards black holes, which still represent the most natural and simplest solution to the fate of gravitational collapse. However, as scientists in general, and as theoretical physicists in particular, it is essential to maintain an unbiased approach towards what we do not know and hence explore both the accepted wisdom and the more exotic interpretations. History teaches us that it is not unusual for the latter to become the former."

Source: ScienceDaily

Scientists crack a decades-old CO2 problem and triple fuel production

 Converting carbon dioxide (CO2) into methanol is widely viewed as a promising way to recycle carbon resources. However, scientists have long faced a difficult challenge when trying to improve the process.

At lower temperatures, converting CO2 into methanol is thermodynamically favorable. The problem is that CO2 becomes difficult to activate under these conditions, resulting in weak catalytic performance. Raising the temperature speeds up the reaction, but it also encourages a competing process known as the reverse water-gas shift reaction, which produces unwanted byproducts and lowers methanol selectivity. This persistent trade-off between catalytic activity and selectivity has limited progress in increasing methanol yields.

New Catalyst Design Overcomes Long-Standing Trade-Off

In a study published in Chem, researchers led by Prof. Jian Sun and Prof. Jiafeng Yu of the Dalian Institute of Chemical Physics (DICP) at the Chinese Academy of Sciences (CAS) developed a new catalyst design aimed at addressing this challenge.

Their approach uses a strong metal-support interaction (SMSI)-driven overlayer structure to spatially separate active sites within the catalyst. This design allows different reaction steps to occur in different locations, improving the efficiency of methanol production from CO2.By restructuring the catalyst surface and changing how reactants adsorb, dissociate, and move through the reaction pathway, the team achieved a space-time yield of 1.2 g·gcat-1·h-1 at 300 ℃ and 3 MPa. That performance is approximately three times higher than that of conventional commercial Cu/Zn/Al catalysts.

Redirecting CO2 Toward Methanol

The researchers found that their catalyst encourages CO2 to adsorb and activate primarily on zirconia (ZrO2) sites. This steers the reaction toward methanol production through the formate pathway.In conventional Cu-based catalysts, activation typically begins by breaking the C=O bond before hydrogenation occurs. The new strategy follows a different sequence. Hydrogenation takes place first on ZrO2 sites, and C=O bond cleavage occurs afterward.

According to the researchers, this change in reaction mechanism significantly reduces the formation of carbon monoxide (CO) byproducts while preserving the strong ability of Cu sites to dissociate H2 efficiently."Our study may provide a new pathway to addressing the long-standing trade-off between activity and selectivity in methanol synthesis from CO2," said Prof. Sun.

Source: ScienceDaily

Reversing prediabetes cuts risk of deadly heart problems by 58%

 People with prediabetes who return their blood sugar levels to a normal range may significantly reduce their chances of developing major cardiovascular problems, according to new research from King's College London published in The Lancet Diabetes & Endocrinology.

The study found that reversing prediabetes by normalizing blood glucose levels was associated with more than a 50% reduction in the risk of dying from cardiovascular disease or being hospitalized for heart failure.

The findings are particularly noteworthy because recent research has suggested that lifestyle changes alone, such as exercising more, losing weight, and improving diet, do not appear to reduce cardiovascular risk in people with prediabetes.

Taken together, the results point to prediabetes remission as a potentially powerful new target for preventing heart disease and improving long-term health outcomes. The findings could also influence how doctors approach treatment for people with prediabetes.

"This study challenges one of the biggest assumptions in modern preventative medicine. For years, people with prediabetes have been told that losing weight, exercising more and eating healthier will protect them from heart attacks and early death. While these lifestyle changes are unquestionably valuable, the evidence does not support that they reduce heart attacks or mortality in people with prediabetes. Instead, we show that remission of prediabetes is associated with a clear reduction in fatal cardiac events, heart failure, and all-cause mortality," explained study lead author Dr. Andreas Birkenfeld, Reader in Diabetes, King's College London and University Hospital Tuebingen.

Prediabetes Affects More Than One Billion People Worldwide

Prediabetes occurs when blood sugar levels are elevated but not high enough to meet the criteria for type 2 diabetes. Although many people with prediabetes eventually develop type 2 diabetes, the condition itself is also linked to a higher risk of cardiovascular disease, one of the leading causes of death worldwide.

The condition is extremely common. About one in five adults in the United Kingdom has either diabetes or prediabetes. In the United States, more than one in three adults are affected, while in China the figure reaches four in ten. Researchers estimate that more than one billion people globally have prediabetes.

Long-Term Studies Reveal Lasting Heart Benefits

The research team, led by Dr. Andreas Birkenfeld of King's College London and University Hospital Tuebingen, reexamined data from two major diabetes prevention studies: the US Diabetes Prevention Program Outcomes Study (DPPOS) and the Chinese DaQing Diabetes Prevention Outcomes Study (DaQingDPOS).

Both studies tracked people with prediabetes for decades and included interventions such as increased physical activity and healthier eating habits.

Researchers found that participants who achieved remission of prediabetes experienced a 58% lower risk of cardiovascular death or hospitalization for heart failure. The benefit remained evident decades after blood glucose levels returned to normal, suggesting that the effects of glucose normalization may be long lasting.

The analysis also showed that people who reversed prediabetes had a 42% lower risk of heart attack, stroke, and other major cardiovascular events.

Importantly, the findings were consistent across both the US and Chinese study populations.

Why Prediabetes Remission May Matter More Than Lifestyle Changes Alone

Earlier analyses of the same studies found that combined lifestyle interventions, including increased exercise and healthier diets, did not significantly reduce cardiovascular disease risk.

Source: Sciendaily

Honey bees have their own personal flight paths and fly them with stunning precision

 Honey bees are far more precise navigators than scientists once realized. Researchers at the University of Freiburg have discovered that individual honey bees follow their own highly consistent flight routes and can repeat them with remarkable accuracy, relying on landmarks in the landscape to stay on course.

The study was led by neurobiologist and behavioral biologist Prof. Dr. Andrew Straw, whose team used a drone to monitor honey bees traveling between their hive and a food source located about 120 meters away in an agricultural setting.

To track the insects during flight, the researchers used a technique called 'Fast Lock-On (FLO) Tracking', developed by Straw's research group. The method involves attaching a tiny reflective marker to each bee. A computer mounted on the drone analyzes reflected light and can identify and track a bee within milliseconds as it flies.

The observations revealed that each honey bee follows its own preferred route and maintains that path with exceptional accuracy on both outbound and return trips. The bees also appear to use features in the surrounding landscape to help guide their journeys.

"Our tracking system makes it possible for the first time to record high-resolution 3D flight paths of honey bees in natural landscapes," explains Straw. "Our recordings show that each bee has its own preferred route and flies it very precisely. You could almost say that each bee has its own personality."

How Honey Bees Use Landmarks to Navigate

The researchers analyzed 255 flight paths collected near Kaiserstuhl, Germany. The study area included hedges, a cornfield, and a tree that stood between the hive and the food source, preventing a direct route.

"We found a high degree of precision in the flight paths. Individual bees repeated their individual flight paths nearly exactly on several flights. They often fly just a few centimeters away from their previous paths," Straw emphasizes.

The most consistent flight behavior occurred near prominent landscape features, particularly the tree. The greatest variation appeared when bees flew above the cornfield, where the scenery offered fewer distinct visual cues.

"Our results suggest that visual landmarks aid the bees' navigation and increase the precision of their flight paths," explains Straw. In contrast, the bees' uncertainty increases in visually monotonous environments.

Honey Bee Navigation vs. the Waggle Dance

The findings also shed new light on the famous waggle dance, the behavior honey bees use to communicate the location of food sources to other members of the colony.

"It was previously known that the directional information in the waggle dance is not entirely accurate," explains Straw. For food sources approximately 100 meters away, the directional information in the waggle dance can deviate by around 30 degrees.

The new research suggests that this lack of precision in the dance is not the result of poor navigation skills. Instead, bees appear to be far more accurate when traveling to locations they already know.

"Our research has shown that individual bees navigate much more accurately to destinations they are familiar with. Even where their flight paths vary most, they deviate from their individual route by only a few degrees. Our results allow us to conclude that the inaccuracy of the waggle dance is not due to the bees' limited navigational abilities. Rather, individual animals are spatially much more accurately oriented than their dance communication would suggest," says Straw.

Source: ScienceDaily

Scientists found a new Alzheimer’s trigger and a drug that stops it

 A promising experimental compound developed by researchers at ETH Zurich could offer a new way to slow the progression of Alzheimer's disease. In studies involving mice, the treatment reduced nerve cell loss, helped the animals live longer, and targeted a biological process that existing Alzheimer's drugs do not address.

The compound, known by researchers as "Compound 10," is the result of nearly two decades of work led by Ursula Quitterer, Professor of Molecular Pharmacology at ETH Zurich.

A Long Search for New Alzheimer's Clues

The research began almost 20 years ago when Quitterer received brain tissue samples from a colleague at Ain Shams University Hospital in Cairo. The samples were collected during tumor surgeries and came from both people with dementia and individuals without the condition.

Those samples helped launch an investigation into a protein called GRK2, which has been the focus of Quitterer's research for many years.

GRK2 plays an important role throughout the body. As a regulatory protein, it helps cells respond to signals and adapt to stress. It is active in several organs, including the heart and the brain, where it supports healthy nerve cell function.

Using both human brain tissue and mouse models of Alzheimer's disease, the ETH Zurich team uncovered evidence that GRK2 may be a major contributor to dementia. Their findings were recently published in the journal Cell Reports Medicine.

When a Protective Protein Turns Harmful

GRK2 exists in two forms inside cells. One form functions normally, while the other becomes inactive through cellular processes.

The researchers found that the inactive version accumulates in large amounts in the brains of people with dementia. Similar patterns were also observed in mice that develop Alzheimer's-like symptoms.

Further experiments revealed that inactive GRK2 molecules clump together inside nerve cells. These clusters attach to mitochondria, the structures often referred to as the "powerhouses" of cells, and interfere with their function.

"The GRK2 aggregates block the pores of the mitochondria, reducing the amount of energy they can supply and leading to a situation of stress inside the cells," Quitterer explains.

The team also found that inactive GRK2 appears to increase the production of amyloid beta, a protein fragment widely associated with Alzheimer's disease.

This creates a damaging cycle. Amyloid beta places additional stress on nerve cells, which leads to the formation of even more inactive GRK2. As more GRK2 accumulates and forms aggregates, the disease process continues to accelerate.

Compound 10 Breaks the Cycle

To interrupt this cycle, the researchers designed and tested several experimental compounds in cell cultures and mice.

Among them, Compound 10 delivered the strongest results. The compound prevented GRK2 molecules from forming harmful aggregates, allowing mitochondria to function more effectively. As a result, amyloid beta deposits were reduced, nerve cells remained healthier, and cell death was slowed.

The benefits extended beyond the brain.

In mice, Compound 10 also appeared to improve heart function and influence aging-related changes. The researchers observed that treated animals developed fewer gray hairs as they grew older.

Source: ScienceDaily