According to research reviewed by Gram, a 2026 study found that LATS proteins help brown fat burn calories as heat. Mice missing these proteins in fat cells made less heat-producing UCP1 and burned less energy in the cold, yet they resisted diet-induced obesity.
Brown fat is the body’s built-in heater, burning energy to produce warmth. A study reviewed by Gram found that a group of proteins called LATS helps control how well brown fat cells make heat. When researchers turned off LATS in brown fat cells of mice, the cells made less of a heat-producing protein called UCP1, and the mice burned less energy in cold conditions. Surprisingly, these same mice were protected from weight gain on a high-fat diet. The researchers do not yet know why. The findings point to a possible new target for future metabolism research, but they come from mice and lab-grown cells, so they cannot yet tell us how to change metabolism in people.
Key Statistics
A 2026 study published in Molecular Metabolism found that mice lacking LATS1 and LATS2 proteins in heat-producing fat cells had lower UCP1 levels in brown fat and burned less whole-body energy during cold exposure.
In a 2026 Molecular Metabolism mouse study, removing LATS1 and LATS2 from heat-producing fat cells impaired the cells’ heat response but still protected mice against diet-induced obesity.
A 2026 study of lab-grown human and mouse brown fat cells found that reducing LATS activity increased levels of the YAP1 and TAZ proteins inside the cell nucleus.
The Quick Take
- What they studied: Scientists wanted to know whether a group of proteins called LATS, which act as on-off switches inside cells, helps brown fat burn energy as heat. They also wanted to understand how these proteins affect body weight.
- Who participated: The study used lab-grown human and mouse brown fat cells and laboratory mice. The exact number of animals or cell samples was not stated in the information provided, and the findings have not been tested directly in people.
- Key finding: When LATS proteins were removed from brown fat cells in mice, the cells made less UCP1, a protein that lets fat burn energy as heat, and the mice burned less energy in the cold. Even so, these mice gained less weight on a high-fat diet, which the researchers could not fully explain.
- What it means for you: This study does not give you a new way to lose weight or boost metabolism today. It adds to scientists’ understanding of how the body makes heat from fat, which may guide future research. Anyone interested in metabolism should rely on proven habits like regular activity, balanced eating, and sleep, and talk with a doctor before making major changes.
The Research Details
The researchers worked in two main settings. First, they grew brown fat cells in the lab, using both human and mouse cells, and changed the levels of LATS proteins to see how the cells responded. They measured genes that control heat production, the amount of UCP1 protein, and how well the cells’ energy-making structures, called mitochondria, used oxygen.
Second, they studied mice that had the LATS proteins removed from their heat-producing fat cells. These mice were exposed to cold temperatures and given a drug called CL-316,243, which mimics a natural signal that tells fat cells to burn energy. The team measured how much energy the mice burned and how much UCP1 was present in their brown fat. They also fed mice a high-fat diet to see how much weight they gained.
To look for a possible mechanism, the researchers examined how LATS proteins interact with other molecules, including YAP1, TAZ, and PPARγ. PPARγ is a protein that helps switch on genes involved in fat and energy processing.
Using both lab cells and living mice allows scientists to test an idea in a simple system first, then check whether it holds up in a whole body. Cell studies can show exactly which molecules interact, while animal studies show what happens to energy use and weight in a living system. Together, these approaches make the findings more convincing than either method alone.
The study was published in Molecular Metabolism, a peer-reviewed scientific journal, which means outside experts reviewed it before publication. The work combines cell experiments with genetic experiments in mice, which strengthens the evidence. However, the study does not state how many mice or cell samples were used, which makes it harder to judge how reliable the numbers are. Results from mice and lab cells often do not transfer directly to people.
What the Results Show
The main finding is that LATS proteins appear to help brown fat cells produce heat. In lab-grown cells from both humans and mice, reducing LATS activity lowered the levels of genes that drive heat production and reduced the amount of UCP1 protein. UCP1 is a key protein that allows fat cells to release energy as heat instead of storing it. The cells also showed changes in how their energy-making structures worked.
The researchers traced part of this effect to a chain of molecular signals. When LATS activity dropped, two related proteins, YAP1 and TAZ, became more stable and built up inside the cell’s nucleus, where genes are switched on or off. TAZ was found to physically interact with PPARγ, a protein that helps control fat and energy genes. When LATS was reduced in mouse cells, PPARγ levels fell and its ability to bind to its target DNA sequence also dropped. This suggests a possible route by which losing LATS signaling could weaken the heat-making program.
The effects were also seen in living animals. Mice that lacked LATS1 and LATS2 in their heat-producing fat cells had less UCP1 in their brown fat tissue. When exposed to cold or to the CL-316,243 drug, these mice burned less energy overall than normal mice. In everyday terms, their bodies were less effective at producing heat from fat when they needed it most.
Despite this weaker heat response, the same mice were protected from diet-induced obesity. When fed a high-fat diet, they gained less weight than control mice. The researchers describe this as unexpected, and they state that the reason behind this protection remains unresolved. This contrast is the most surprising part of the study and is a clear sign that the link between fat-burning heat and total body weight is more complicated than previously assumed.
The study showed that the effects of LATS proteins were strongest for LATS2, one of the two proteins, although removing both LATS1 and LATS2 produced stronger effects on PPARγ levels than removing LATS2 alone. This suggests the two proteins work together, with LATS2 playing a particularly important role. The team also found that the changes were consistent across human and mouse cells, which supports the idea that this pathway may matter in more than one species.
The unexpected weight protection is potentially the most significant secondary outcome. It hints that the body may have other ways of managing energy and fat storage that do not depend on heat production alone. This is important because it shows that simply boosting or reducing brown fat activity may not translate into a simple weight outcome.
Brown fat has been a major focus of metabolism research for years because it can burn energy as heat. Earlier work has linked the Hippo signaling pathway, which includes LATS proteins, to organ growth and cell behavior. The YAP1 and TAZ proteins and the PPARγ regulator have also been studied in fat biology. This study connects those existing pieces by showing how they may work together to control brown fat heat production. The finding that this pathway can reduce heat output while also protecting against weight gain is new and does not yet have a clear explanation in existing research.
The most important limitation is that most of the evidence comes from lab-grown cells and mice, and results in these settings do not always apply to people. The study also does not clearly explain why mice without LATS proteins resisted weight gain, so the overall effect on body weight remains uncertain. The information provided does not state how many animals or cell samples were used, which makes it harder to judge statistical strength. Additionally, the mice were given a specific drug and cold exposure to test their heat response, which may not reflect everyday life. Finally, the molecular mechanisms identified are only partly understood, so more research is needed before any practical conclusions can be drawn.
The Bottom Line
At this stage, the research supports the idea that LATS proteins play a real role in how brown fat produces heat, based on consistent results across lab cells and mice. However, there is no evidence yet that changing LATS activity in people would help with weight loss or metabolism. Confidence in the basic biology is moderate, while confidence in any practical health benefit for people is low. Standard, proven approaches such as regular physical activity, balanced eating, and adequate sleep remain the best-supported options for healthy weight management.
Researchers studying obesity, metabolism, and fat biology should pay close attention because this study identifies a possible new pathway to investigate. People managing weight or metabolic conditions should be aware of the research but should not change their habits based on it. Anyone considering supplements or treatments claiming to boost brown fat should be cautious, since this study does not support such claims. Readers without a specific interest in metabolic science may find the details less relevant to daily life.
Findings like these usually take many years to move from mouse studies to human research. Early human studies would need to confirm that the same proteins work similarly in people and that changing them is safe. Based on typical research timelines, any practical treatment derived from this work would likely be a decade or more away, if it develops at all.
Frequently Asked Questions
What are LATS proteins and how do they affect brown fat?
LATS proteins are on-off switches inside cells that belong to the Hippo signaling pathway. In a 2026 study, they helped control brown fat’s heat-producing ability, and reducing them lowered UCP1 protein levels in both lab cells and mice.
Does this study prove that brown fat research can help with weight loss?
No single study proves that. This 2026 Molecular Metabolism research was done in mice and lab-grown cells. Surprisingly, mice missing LATS proteins had weaker heat production but resisted diet-induced obesity, and the reason is still unknown.
Can I increase my brown fat activity by changing my diet or exercise?
This study does not test diet or exercise changes, so it cannot answer that question. Regular physical activity and balanced eating are well supported for overall health, and a doctor can advise on whether any approach fits your needs.
What is UCP1 and why do scientists care about it?
UCP1 is a protein found in brown fat that lets cells release energy as heat instead of storing it. Researchers track UCP1 levels because they reflect how well brown fat burns energy, which is why it appeared as a key measure in this 2026 study.
Want to Apply This Research?
- Track your daily steps, active minutes, and total weekly exercise, and log your weight once a week at the same time of day. Also record your average time in bed to see how sleep relates to your activity and weight trends over several weeks.
- Use the app to set a realistic goal of adding 10 minutes of brisk walking each day, and review progress weekly. If you spend time in cool environments, consider logging short periods of light activity in mild cold, but avoid extreme cold exposure without medical guidance.
- Review trends over three-month periods rather than day-to-day changes. Note any changes in energy, appetite, or temperature tolerance in a journal alongside your activity and weight data, and share the trends with your healthcare provider at regular checkups.
This article summarizes a 2026 laboratory and animal study and is for general information only. The research was conducted in mice and cultured cells, and its findings have not been tested in people. This content is not medical advice. Please consult a qualified healthcare provider before making changes to your diet, exercise, weight management, or any treatment plan.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.