Cold-Brewed Hawthorn Juice Reshaped Gut Bacteria and Blocked Fat Gain in Mice

If you have ever wondered whether a fruit as ordinary as hawthorn could do something meaningful for your gut, a new mouse study offers a specific, testable answer, though not yet one you can act on for yourself. Researchers in China fed mice a high-fat diet designed to induce obesity, then gave some of them a cold-brewed hawthorn juice alongside it. The juice-treated mice gained less weight and body fat than untreated mice on the same diet, and the researchers traced the effect back to a reshaped gut microbiome, then went a step further and proved the microbiome itself was doing the work.

Key Takeaways

• Cold-brewed hawthorn juice (HAW) reduced high-fat-diet weight gain, fat mass, and liver fat buildup in mice, while improving glucose tolerance and insulin sensitivity.
• The juice shifted gut bacteria composition, lowering the Firmicutes/Bacteroidetes (F/B) ratio, a pattern often associated with obesity, and increasing bacteria such as Odoribacter and Alistipes that are linked to leaner metabolic profiles.
• A fecal microbiota transplant (FMT) experiment, giving only the gut bacteria from hawthorn-treated mice to a separate group of obese mice that never drank the juice, reproduced the anti-obesity effects, supporting a causal role for the microbiome rather than just an association.
• This is animal-only research with small group sizes (n=6 per group) using a specific cold-brew preparation and dose; whether human hawthorn juice or tea would do the same is unconfirmed.

Cold-Brewed Hawthorn Juice Curbed High-Fat-Diet Weight Gain in Mice

Mice fed a high-fat diet (HFD, 60 percent of calories from fat) alongside daily doses of cold-brewed hawthorn juice gained significantly less weight and body fat over eight weeks than mice on the identical diet without it, according to the study published in the Journal of Functional Foods by researchers at Hainan Medical University and Guangzhou University of Chinese Medicine. The team, led by Yi Qiu and colleagues, prepared the juice (HAW) by crushing fresh hawthorn fruit and steeping it in water at 4 degrees Celsius for 12 hours, a cold-brew method chosen because heat can degrade some of the phenolic compounds thought to drive the fruit's effects. Male mice received either a low dose (0.5 g/kg per day) or a high dose (0.8 g/kg per day) of the juice by daily oral gavage for eight weeks. Beyond slimmer body composition, the treated mice also showed better glucose tolerance and insulin sensitivity, higher oxygen consumption and heat production during a cold challenge, and less fat buildup in the liver, an early marker of metabolic-associated fatty liver disease (MAFLD).

Why Gut Bacteria Composition Matters for Metabolic and Digestive Health

Gut bacteria are not just passengers, they help extract energy from food, produce signaling molecules, and interact with the immune system in ways that researchers increasingly tie to obesity, type 2 diabetes, and inflammatory conditions. One widely studied signal is the Firmicutes/Bacteroidetes (F/B) ratio, the relative abundance of two dominant bacterial phyla, which some human and animal studies link to obesity risk, although evidence on how consistent that link is across populations remains mixed. In this study, hawthorn juice lowered the F/B ratio and shifted the balance of specific bacterial genera, reducing groups like Blautia and Acetatifactor that the researchers associated with obesity, while increasing Alistipes, Odoribacter, Muribaculaceae, and Butyricicoccus, genera the authors link to leaner metabolic states. For anyone researching gut-related conditions, from metabolic syndrome to IBS, this is the kind of mechanistic detail that matters: it is not just "eat this fruit," it is a specific, traceable shift in which bacteria dominate the gut.

How the FMT Experiment Confirmed the Bacteria Were Doing the Work

To test whether the microbiome shift was a side effect of the juice or the actual cause of the metabolic improvements, the researchers ran a separate fecal microbiota transplant (FMT) experiment. Twelve new mice first had their existing gut bacteria wiped out with a five-day course of antibiotics (neomycin, ampicillin, metronidazole, and vancomycin). Half then received a fecal transplant drawn from the high-dose hawthorn-juice mice, while the other half received plain water, and neither group was given the juice itself. The mice that received the hawthorn-associated microbiome alone still gained less weight and fat, showed better glucose tolerance, and had less liver and adipose tissue lipid buildup than the water-gavaged group, along with lower endotoxin levels in blood and liver. The transplant recipients also showed the same signature bacterial shifts as the original juice-fed mice, including reduced Acetatifactor and increased Odoribacter and Alistipes. Because the benefit showed up in mice that never touched a drop of hawthorn juice, the design points toward the gut microbiota itself, not just the fruit's direct chemistry, as a driver of the effect.

What This Could Mean for Human Gut and Metabolic Health

The mechanistic story the researchers pieced together is that hawthorn's polyphenols and other compounds reshape the gut microbiota, and that reshaped microbiota in turn promotes fat burning over fat storage. The treated mice showed increased activity of thermogenesis genes and proteins, including UCP1 and PGC-1α, in brown and "beige" fat, the heat-generating fat tissue known in humans to be inversely linked to obesity and metabolic disease, alongside reduced fat-storage signaling (SREBP-1C, ChREBP, DGAT2) in the liver. The researchers also profiled blood metabolites and found levels of several compounds, including (+)-lariciresinol, Bavachin, Ponicidin, and 4-Hydroxycordoin, that correlated with the microbiota shift. For a reader whose health concerns trace back to gut function, this adds hawthorn to a growing list of dietary compounds under investigation for a gut-mediated metabolic effect, alongside broader interest in hawthorn's established cardiovascular and lipid-lowering properties. None of this means a supplement or juice is a proven weight-loss or liver-health intervention in people, and it is not something to substitute for medical care around diagnosed metabolic or digestive conditions.

What This Study Doesn't Yet Show

This was mouse-only research, using male C57BL/6J mice in small groups of six per condition, so it cannot establish how, or whether, the same dose and preparation would affect a human gut microbiome or metabolism. The hawthorn juice was a specific cold-brew extract of one cultivar at doses calibrated to mouse body weight, not a quantity translatable to a cup of hawthorn tea or a commercial supplement. The fecal transplant, too, came from a mouse donor into antibiotic-depleted mice, a setup that isolates causality in this model but does not mirror how a person's existing microbiome would respond to hawthorn juice without first being wiped out. The study also did not isolate which specific bacteria or metabolites are doing the causal work, only that the community as a whole, when transplanted, reproduced the effect.

What Comes Next for Hawthorn and the Gut Microbiome

The authors frame their findings as a starting point for "daily functional fruit dietary interventions," language that signals more translational research, not a finished product. Logical next steps include testing whether hot-brewed or commercially processed hawthorn preparations retain the same effect, since the researchers specifically chose cold-brewing to preserve phenolic compounds they believed heat might degrade, and isolating which individual bacteria or metabolites, among the ones identified here, are necessary and sufficient to reproduce the anti-obesity effect. Human trials, with human donors and human gut microbiomes, would be the eventual test of whether any of this translates beyond a mouse cage.

Common Questions

Does this mean drinking hawthorn tea or juice can help me lose weight? No. This study was conducted entirely in mice using a specific cold-brewed extract and controlled doses, and no human trials of hawthorn juice for weight or metabolic outcomes were part of this research.

What is the Firmicutes/Bacteroidetes ratio, and why does it matter? It is the relative balance of two of the largest bacterial groups in the gut. A higher ratio has been associated with obesity in some studies, though the evidence is mixed, and in this study hawthorn juice lowered the ratio alongside improved metabolic markers.

What is a fecal microbiota transplant, and why did the researchers use one? It involves transferring gut bacteria from one animal (or person) into another, here from hawthorn-treated donor mice into separate recipient mice. Because the recipients improved without ever receiving the juice itself, it strengthens the case that the microbiome, not just the fruit's direct chemistry, is driving the effect.

Is cold-brewed hawthorn juice different from the dried hawthorn tea or candied hawthorn many people already eat? Likely yes in composition, though this study did not directly compare them. The researchers chose cold-brewing specifically because prior research suggests heat can degrade some of the phenolic compounds in hawthorn, meaning hot-processed products may not contain the same profile of active compounds tested here.

References

1. Yi Qiu, Zaibin Xu, Yan Chen, et al. (2026). Cold-brewed hawthorn juice ameliorates high-fat diet-induced obesity in mice by regulating gut microbiota and lipid metabolism. Journal of Functional Foods. https://doi.org/10.1016/j.jff.2026.107485
2. Fabien Magne, Martin Gotteland, Lea Gauthier, et al. (2020). The Firmicutes/Bacteroidetes Ratio: A Relevant Marker of Gut Dysbiosis in Obese Patients?. Nutrients. https://doi.org/10.3390/nu12051474
3. Zhengxiao Zhang, Valentin Mocanu, Chenxi Cai, et al. (2019). Impact of Fecal Microbiota Transplantation on Obesity and Metabolic Syndrome—A Systematic Review. Nutrients. https://doi.org/10.3390/nu11102291
4. The effects of Crataegus pinnatifida (Chinese hawthorn) on metabolic syndrome: A review. NIH. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6556496/