Researchers followed nearly 47,500 people with a fatty liver condition for over 13 years to see if eating a Mediterranean diet (lots of vegetables, fish, nuts, and olive oil) could help. They found that people who followed this diet most closely had about 45% lower risk of serious liver problems and 15% lower risk of death from any cause compared to those who followed it least. The study suggests that certain healthy fats and proteins in the Mediterranean diet may be the key ingredients protecting the liver.

The Quick Take

  • What they studied: Whether eating a Mediterranean-style diet (rich in vegetables, fish, nuts, and olive oil) could prevent serious liver problems and early death in people with fatty liver disease
  • Who participated: 47,429 people from the UK Biobank who had fatty liver disease but no serious liver problems at the start of the study. Researchers tracked them for an average of 13.3 years
  • Key finding: People who most closely followed a Mediterranean diet had 45% lower risk of developing serious liver complications and 15% lower risk of dying from any cause compared to those who followed it least closely
  • What it means for you: If you have fatty liver disease, eating more Mediterranean-style foods (vegetables, legumes, fish, nuts, and using olive oil) may help protect your liver and potentially help you live longer. However, this study shows association, not that diet alone cures the condition—talk to your doctor about a complete treatment plan

The Research Details

This was a prospective cohort study, which means researchers followed the same group of people over time and tracked what happened to them. Participants answered detailed questions about their eating habits, and researchers used a scoring system to measure how closely each person followed a Mediterranean diet. They also measured 143 different substances in participants’ blood using advanced laboratory technology to understand the chemical changes happening in their bodies. Over 13 years, researchers recorded who developed serious liver problems and who died, then used statistical analysis to see if diet and blood chemistry patterns predicted these outcomes.

The Mediterranean diet score was based on eating more vegetables, legumes (beans and lentils), nuts, fish, and healthy oils while eating less red meat and processed foods. Researchers also looked at individual food groups separately to see which ones mattered most. The blood tests measured fats, proteins, and other molecules that reflect overall health and metabolism.

This research approach is strong because it follows real people over many years in their actual lives, rather than just testing diet in a laboratory. By measuring both diet and blood chemistry, researchers could see not just whether diet helped, but also understand the biological mechanisms—the ‘why’ behind the benefits. This helps doctors understand which specific nutrients are most protective.

This study has several strengths: it’s large (nearly 47,500 people), follows participants for over a decade, uses validated methods to assess diet, and measures multiple biological markers. The study was conducted in a well-documented population (UK Biobank) with reliable health records. However, people who choose to eat Mediterranean diets may differ from others in ways beyond just diet, so we can’t be completely certain diet alone caused the benefits. The study shows association, not definitive cause-and-effect.

What the Results Show

During the 13-year follow-up, 296 people developed serious liver-related complications and 3,616 people died from any cause. People with the highest Mediterranean diet scores (6-9 out of 9) had significantly better outcomes than those with the lowest scores (0-3). Specifically, high adherence reduced the risk of serious liver problems by 45% and reduced overall death risk by 15%.

The relationship between diet quality and health benefits appeared to be dose-dependent, meaning that the more closely people followed the Mediterranean diet, the better their outcomes. Even moderate improvements in diet quality showed benefits. Vegetables and legumes were particularly protective against liver complications, while vegetables, nuts, fish, and moderate alcohol consumption were most protective against death.

When researchers analyzed the blood chemistry data, they found that 46 out of 143 measured substances were significantly different in people who followed the Mediterranean diet more closely. The most important protective substances were omega-3 fatty acids (healthy fats found in fish), the ratio of omega-3 to total fatty acids, and albumin (a protein made by the liver). These three substances accounted for a substantial portion of the diet’s protective effects—together explaining about 8-24% of the benefit against liver complications and 19-23% of the benefit against death.

The study identified specific food components that mattered most: fish and nuts appeared particularly important for reducing death risk, while beans and legumes were especially protective for liver health. The ratio of unsaturated to saturated fats (healthier to less healthy fats) was also important. Moderate alcohol consumption (as part of the Mediterranean diet pattern) was associated with benefits, though this doesn’t mean alcohol itself is protective—it reflects the overall healthy lifestyle pattern. The research suggests that the Mediterranean diet works through multiple pathways, not just one mechanism, which explains why the diet is so effective.

Previous research has recommended the Mediterranean diet for fatty liver disease, but this study is one of the largest and longest to specifically track whether it prevents serious complications and death. Earlier studies mostly looked at whether the diet improved liver fat content or liver enzymes, but didn’t follow people long enough to see if it prevented serious outcomes. This research confirms and extends previous findings by showing that the diet’s benefits extend to preventing life-threatening complications and extending lifespan. The identification of specific protective metabolites (blood chemicals) provides new understanding of how the diet works at a biological level.

The study cannot prove that diet alone caused the benefits—people who choose Mediterranean diets may be healthier in other ways too (exercise, stress management, healthcare access). The study population was primarily from the UK, so results may not apply equally to all populations. The diet assessment was based on questionnaires about past eating habits, which relies on people’s memory and honesty. The study measured blood chemistry at only one point in time, so researchers couldn’t track how these substances changed over time. Additionally, the study identified associations with 46 metabolites, but only a few were thoroughly analyzed for their role in the diet’s benefits, so other important mechanisms may have been missed.

The Bottom Line

If you have fatty liver disease, consider adopting Mediterranean diet principles: eat more vegetables, legumes, nuts, and fish; use olive oil as your main cooking oil; eat less red meat and processed foods; and consume alcohol only moderately if at all (HIGH confidence). These changes appear to reduce serious liver complications by about 45% and overall death risk by about 15% based on this evidence. Work with your doctor to develop a complete treatment plan, as diet is one important component but may not be sufficient alone (MODERATE confidence). Track your progress with your healthcare provider through regular liver function tests and imaging.

This research is most relevant for people who have been diagnosed with fatty liver disease (MASLD). It’s also valuable for people at risk of developing fatty liver disease (those with obesity, diabetes, or metabolic syndrome). Healthcare providers managing liver disease should consider recommending Mediterranean diet patterns. The findings may also interest people interested in disease prevention and longevity. This research is less directly applicable to people without liver disease, though the Mediterranean diet has broad health benefits for everyone.

Based on this research, meaningful improvements in liver health markers typically appear within weeks to months of dietary changes, but protection against serious complications develops over years. The study followed people for 13 years, so the most dramatic benefits took considerable time. Don’t expect overnight results, but consistent adherence over months and years appears to provide substantial protection. Regular check-ups with your doctor every 3-6 months can help track improvements in liver function.

Want to Apply This Research?

  • Track daily servings of Mediterranean diet components: vegetables (goal: 3+ servings), legumes (goal: 2-3 times weekly), fish (goal: 2-3 times weekly), nuts (goal: 1 ounce daily), and olive oil use. Create a simple daily checklist within the app marking which components you consumed each day, with a weekly Mediterranean diet adherence score (0-9 scale matching the research study).
  • Set a specific, measurable goal such as ‘Add one fish meal per week’ or ‘Replace butter with olive oil for cooking’ or ‘Add legumes to three meals this week.’ Use the app to plan Mediterranean meals, set reminders for grocery shopping for Mediterranean ingredients, and log meals that fit the pattern. Create a visual progress tracker showing weekly adherence scores to maintain motivation.
  • Track Mediterranean diet adherence weekly using the 9-point score. Correlate this with any available health metrics (weight, energy levels, digestion). Schedule monthly check-ins to review adherence patterns and identify barriers. Connect with your healthcare provider to track liver function tests (ALT, AST, GGT enzymes) every 3-6 months to see if dietary changes are improving liver health. Use the app to maintain a food journal that can be shared with your doctor or dietitian.

This research shows that Mediterranean diet patterns are associated with better liver health outcomes in people with fatty liver disease, but association does not prove causation. This information is educational and should not replace professional medical advice. If you have fatty liver disease or any liver condition, consult with your healthcare provider or a registered dietitian before making significant dietary changes. This study does not constitute medical treatment recommendations. Individual results may vary based on genetics, overall lifestyle, and other health conditions. Always work with your healthcare team to develop a comprehensive treatment plan for liver disease.