A new study found that Vitamin K2 might help treat a common liver disease called MASLD, which affects about one in three people worldwide. Researchers gave mice with fatty livers a supplement of Vitamin K2 for 8 weeks and discovered it reduced fat buildup in their livers and improved how their liver cells work. The key finding was that Vitamin K2 appears to work by changing the bacteria in the gut, which then helps the liver function better. While these results are promising, this research was done in mice, so scientists need to test whether it works the same way in humans before people should start taking it as a treatment.

The Quick Take

  • What they studied: Whether Vitamin K2 could help treat fatty liver disease by changing gut bacteria and improving how liver cells produce energy
  • Who participated: 80 young mice (4-5 weeks old) were used in the study. Some ate a high-fat diet to develop fatty liver disease, while others ate normal food as a comparison group
  • Key finding: Mice that received Vitamin K2 had significantly less fat in their livers, better liver function, and healthier gut bacteria compared to mice that didn’t receive it. The improvements appeared to happen because Vitamin K2 increased helpful bacteria called Lactobacillus in the gut
  • What it means for you: This research suggests Vitamin K2 might someday help treat fatty liver disease in humans, but much more testing is needed. Don’t start taking Vitamin K2 supplements for liver disease without talking to your doctor first, as this study was only done in mice

The Research Details

Scientists created fatty liver disease in mice by feeding them a high-fat diet for 16 weeks. Then they gave some of these sick mice Vitamin K2 supplements for the last 8 weeks while continuing the high-fat diet. They compared these mice to a group that ate normal food the whole time and a group that ate high-fat food without any supplement. The researchers looked at liver tissue under a microscope, measured fat levels in the blood, and analyzed the bacteria living in the mice’s intestines using genetic testing.

This study design is important because it shows not just that Vitamin K2 helped, but also how it helped. By analyzing the gut bacteria and using special techniques to block or transfer bacteria between mice, the researchers could prove that the benefits came from changes in gut bacteria, not just from Vitamin K2 directly. This helps scientists understand the actual mechanism of how the vitamin works

This is a well-designed animal study with clear groups for comparison and multiple ways of measuring results. The researchers used several different testing methods to confirm their findings. However, because this was done in mice rather than humans, the results may not work exactly the same way in people. Animal studies are important first steps, but human testing is needed before this becomes a real treatment

What the Results Show

Mice that received Vitamin K2 had much lower levels of fat in their livers compared to mice that only ate the high-fat diet. Their liver enzymes (ALT and AST), which indicate liver damage, were also significantly lower, suggesting their livers were healthier. The Vitamin K2 group also had better cholesterol and triglyceride levels in their blood. Most importantly, when researchers looked at the gut bacteria, they found that Vitamin K2 increased the amount of helpful bacteria called Lactobacillus. When they transferred these bacteria from treated mice to untreated mice, the untreated mice also improved, proving that the bacteria were responsible for much of the benefit.

The study found that Vitamin K2 reduced inflammation in the liver by decreasing immune cells that cause damage. It also improved how well the mitochondria (the energy factories inside cells) worked in liver cells. The researchers identified a specific pathway called SIRT3 that appeared to be activated by Vitamin K2, and this pathway is known to be important for protecting cells from damage

Earlier studies had shown that Vitamin K2 might help with mitochondrial problems in mice eating high-fat diets, but nobody had fully understood how it worked. This research builds on those earlier findings by showing the complete picture: Vitamin K2 changes gut bacteria, which then improves how liver cells work. This is consistent with growing evidence that gut bacteria play a major role in liver health

The biggest limitation is that this study was only done in mice, not humans. Mouse bodies don’t always work exactly like human bodies. The study also only lasted 8 weeks of treatment, so we don’t know if the benefits would continue longer or if there might be long-term side effects. The study didn’t test different doses of Vitamin K2 to find the best amount. Finally, the mice were all the same age and genetic type, so results might be different in people of different ages or genetic backgrounds

The Bottom Line

Based on this research, Vitamin K2 shows promise as a potential treatment for fatty liver disease, but it’s still in the early research stage. Current evidence level: Low to Moderate (animal study only). Do not start taking Vitamin K2 supplements specifically for liver disease without medical supervision. If you have fatty liver disease, work with your doctor on proven treatments like weight loss, exercise, and dietary changes. Vitamin K2 might be considered as an additional option in the future once human studies are completed

People with fatty liver disease or those at risk for it (overweight, diabetic, or with metabolic syndrome) should be aware of this research. However, it’s not yet ready for general use. Researchers studying liver disease and gut health should pay attention to these findings. People currently taking blood thinners should be especially careful about Vitamin K2 supplements, as Vitamin K can interfere with these medications

In the mice, improvements appeared within 8 weeks. If this works in humans, it would likely take several weeks to months to see benefits. However, human studies would need to be done first to determine the actual timeline

Want to Apply This Research?

  • Track liver health markers if you have access to them: measure ALT and AST levels through blood tests every 3 months, track abdominal bloating or discomfort daily, and monitor energy levels on a 1-10 scale. Also track dietary fat intake and exercise minutes per week
  • If your doctor approves, you could increase Vitamin K2-rich foods in your diet (like fermented foods, aged cheeses, and certain dairy products) while simultaneously improving gut health through fiber intake and probiotic-rich foods. Use the app to log these foods and track any changes in how you feel
  • Set up monthly check-ins to review liver function test results with your healthcare provider. Track digestive health, energy levels, and any symptoms of liver problems. Monitor weight and waist circumference weekly. Keep a food diary to ensure you’re maintaining healthy eating habits that support both liver and gut health

This research was conducted in mice and has not been tested in humans. The findings should not be interpreted as medical advice or a recommendation to take Vitamin K2 supplements for liver disease. Fatty liver disease is a serious condition that requires professional medical evaluation and treatment. If you have or suspect you have fatty liver disease, consult with your healthcare provider before making any dietary changes or starting supplements. Vitamin K2 can interact with blood-thinning medications like warfarin. This summary is for educational purposes only and does not replace professional medical advice.