A 2026 research study found that Pediococcus acidilactici Z123, a newly discovered probiotic bacteria, reduced cholesterol levels and weight gain in mice fed a high-fat diet by changing how their bodies process fats and cholesterol. According to Gram Research analysis, the bacteria worked by reducing genes that make cholesterol while increasing genes that break down fats. However, these results are from mouse studies, and human trials are needed before this probiotic can be recommended as a cholesterol treatment.
Researchers discovered that a specific type of beneficial bacteria called Pediococcus acidilactici Z123 may help reduce high cholesterol levels. In a study using mice fed a high-fat diet, this probiotic strain reduced weight gain, lowered cholesterol in the blood, and improved liver health. The bacteria worked by changing how the body processes fats and cholesterol through several biological pathways. While these results are promising, the research was conducted in mice, so scientists need to test whether these benefits work the same way in humans before recommending it as a treatment.
Key Statistics
A 2026 research study of mice found that Pediococcus acidilactici Z123 probiotic bacteria reduced excessive weight gain and lowered blood cholesterol levels while improving liver and fat tissue health in animals fed a high-fat diet.
According to the 2026 research, Pediococcus acidilactici Z123 reduced cholesterol production by downregulating Hmgcr and Srebf1 genes while simultaneously increasing genes responsible for fat breakdown (Cpt1a and Pparα) and bile acid synthesis (Cyp7a1).
The 2026 study confirmed that Pediococcus acidilactici Z123 possessed desirable probiotic safety characteristics including gastrointestinal fluid tolerance, antibiotic susceptibility, and no hemolytic activity in laboratory testing.
The Quick Take
- What they studied: Whether a new probiotic bacteria strain could lower cholesterol and reduce fat buildup in mice eating a high-fat diet, and how it works inside the body.
- Who participated: Laboratory mice that were fed a high-fat diet to develop high cholesterol, compared to control groups. The exact number of mice wasn’t specified in the abstract.
- Key finding: Mice given Pediococcus acidilactici Z123 showed reduced weight gain, lower cholesterol levels, improved liver health, and changes in how their bodies processed fats and cholesterol.
- What it means for you: This probiotic strain shows promise as a natural way to help manage cholesterol, but human studies are needed first. Don’t replace cholesterol medications with probiotics without talking to your doctor.
The Research Details
Scientists first tested the new probiotic bacteria in laboratory conditions to confirm it had beneficial properties like surviving stomach acid and sticking to intestinal walls. They then gave the bacteria to mice that had developed high cholesterol from eating a high-fat diet. The researchers measured changes in the mice’s weight, blood cholesterol levels, liver tissue, and fat tissue. They also analyzed how the bacteria changed the mice’s metabolism using advanced molecular techniques and genetic testing.
The study examined multiple biological pathways to understand exactly how the bacteria lowered cholesterol. This included looking at how the bacteria affected fat breakdown, cholesterol production, and bile acid metabolism—the body’s natural way of managing cholesterol.
Understanding the specific mechanisms of how probiotics work is important because it helps scientists develop better probiotic products and predict whether they’ll work in humans. Most previous research focused on Lactobacillus bacteria, so studying a different probiotic strain expands our knowledge of which bacteria might help with cholesterol.
The study was published in a peer-reviewed scientific journal focused on probiotics. The researchers used multiple advanced techniques to verify their findings, including genetic analysis and metabolic profiling. However, the study was conducted only in mice, which limits how much we can apply the results to humans. The abstract doesn’t specify the exact number of mice used, which makes it harder to assess statistical power.
What the Results Show
Mice receiving Pediococcus acidilactici Z123 showed significant improvements across multiple health markers. The bacteria reduced excessive weight gain and decreased the amount of fat stored around internal organs (visceral fat). Blood cholesterol levels improved, meaning less cholesterol circulating in the bloodstream. When researchers examined liver and fat tissue under a microscope, they saw that the tissue structure looked healthier in treated mice compared to untreated controls.
The bacteria achieved these effects by influencing several biological pathways simultaneously. It reduced the activity of genes responsible for making new cholesterol in the body (specifically Hmgcr and Srebf1 genes) while increasing genes that help break down fats (Cpt1a and Pparα). The probiotic also boosted genes involved in bile acid production (Cyp7a1), which is the body’s natural way of eliminating cholesterol.
The research confirmed that Pediococcus acidilactici Z123 had important probiotic characteristics needed for safety and effectiveness. The bacteria could survive in acidic stomach conditions, stick to intestinal walls, and showed no harmful effects like destroying red blood cells. It was also sensitive to antibiotics, meaning it wouldn’t contribute to antibiotic resistance problems. The bacteria influenced tryptophan metabolism and other metabolic pathways, suggesting it affects overall body chemistry in beneficial ways.
Previous research has shown that Lactobacillus bacteria can lower cholesterol, but fewer studies have examined Pediococcus species. This research fills that gap by demonstrating that Pediococcus acidilactici Z123 works through similar pathways to Lactobacillus strains but may offer additional benefits. The finding that this bacteria affects multiple metabolic pathways simultaneously suggests it might be more effective than single-action treatments.
The most significant limitation is that this study used mice, not humans. Mouse metabolism differs from human metabolism, so results may not translate directly. The abstract doesn’t specify how many mice were used, making it impossible to assess whether the sample size was adequate. The study doesn’t compare this probiotic to existing cholesterol medications or other probiotic strains, so we don’t know if it’s more or less effective. Long-term effects in humans are unknown, and the optimal dose for humans hasn’t been determined.
The Bottom Line
Based on this research, Pediococcus acidilactici Z123 shows promise as a potential cholesterol-management tool, but confidence in human application is currently low. Do not use this as a replacement for prescribed cholesterol medications. If interested in probiotic supplements, discuss options with your healthcare provider. More human studies are needed before specific dosage recommendations can be made.
People with high cholesterol or those at risk for heart disease should be aware of this research as a potential future option. Healthcare providers researching new probiotic treatments should follow this development. People currently taking cholesterol medications should not change their treatment based on this animal study. Those with compromised immune systems should consult doctors before trying new probiotics.
In mice, the benefits appeared during the study period, but the exact timeline wasn’t specified. In humans, if this probiotic proves effective, benefits would likely take weeks to months to appear, similar to other dietary interventions. Don’t expect immediate results if this becomes available as a supplement.
Frequently Asked Questions
Can I use this probiotic to replace my cholesterol medication?
No. This research was conducted only in mice, and human studies haven’t been completed. Continue taking prescribed cholesterol medications as directed by your doctor. Always consult your healthcare provider before making changes to cholesterol treatment.
When will this probiotic be available for human use?
The 2026 study is preliminary research. Typically, animal studies must be followed by human clinical trials, which can take several years. There’s no current timeline for human availability, and regulatory approval would be required.
How does Pediococcus acidilactici Z123 lower cholesterol differently than other probiotics?
This strain affects multiple pathways simultaneously, including fat breakdown, cholesterol production, and bile acid metabolism. Most previous research focused on Lactobacillus bacteria, so this represents a newer approach, but direct comparisons in humans haven’t been made yet.
Is this probiotic safe to take with other medications?
The study showed the bacteria was safe in mice with no harmful effects, but human safety data doesn’t exist yet. Any new supplement should be discussed with your doctor, especially if you take medications, as probiotics can sometimes interact with drugs.
What should I do if I want to try probiotics for cholesterol now?
Talk to your doctor about established probiotic strains with existing human research. Don’t wait for Pediococcus acidilactici Z123 to become available. Your doctor can recommend evidence-based options that may help alongside your current cholesterol management plan.
Want to Apply This Research?
- Track daily probiotic supplement intake (if recommended by your doctor) alongside weekly cholesterol levels or monthly blood test results to monitor effectiveness over time.
- Add a daily probiotic supplement reminder to your app routine, paired with tracking your high-fat food intake to see how the combination affects your cholesterol markers.
- Log probiotic consumption daily and record cholesterol test results every 3 months to identify patterns and determine if the supplement is working for your individual metabolism.
This research was conducted in mice and has not been tested in humans. The findings should not be used to replace prescribed cholesterol medications or medical advice from your healthcare provider. Pediococcus acidilactici Z123 is not currently available as a commercial product for human use. Always consult with your doctor before starting any new supplement, especially if you have high cholesterol, take cholesterol medications, or have a compromised immune system. Individual results may vary, and this probiotic strain may not work the same way in humans as it did in the animal study.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.