Green Mediterranean Diet Rewires Folate Pathways
BGU-led study finds Mankai-rich Green Mediterranean diet boosts folate pathways tied to cardiometabolic health.
A new international clinical intervention study published in Clinical Nutrition reveals the molecular and transcriptomic mechanisms through which a dietary intervention may beneficially influence gene expression. The study, led by Prof. Iris Shai and Dr. Hila Zelicha Peer from Ben-Gurion University of the Negev, in collaboration with researchers from Leipzig University, the Leipzig Center of Metabolism (LieCeM), and Harvard University, provides new evidence that specific plant-derived nutrients may function as an “Epigenetic Pencil” – shaping cellular health through nutrition.
Researchers found that adherence to the Green Mediterranean (Green-MED) diet resulted in a marked increase in circulating folate levels compared with both a traditional Mediterranean diet and standard healthy dietary guidelines. This increase was not merely a passive nutritional marker; rather, it appeared to fuel one-carbon metabolism, a critical biochemical pathway responsible for methylation processes that regulate gene expression, support DNA maintenance, and contribute to metabolic health.
Participants who adopted the Green-MED diet—a polyphenol-rich dietary pattern that includes green tea, walnuts, and a daily shake containing the aquatic plant Mankai (Wolffia globosa) while reducing red and processed meat consumption—experienced a significant rise in serum folate concentrations. Laboratory analyses demonstrated that these elevated folate levels were strongly associated with improvements in insulin sensitivity (HOMA-IR), reductions in inflammatory markers such as IL-6, improvements in the triglyceride-to-HDL cholesterol ratio, and reductions in both visceral and liver fat accumulation.
The findings advance the emerging field of Nutri-Omics, demonstrating how precision nutrition may help compensate for inherited genetic predispositions. Researchers focused on a common variant of the MTHFR gene (rs1801133), which reduces the activity of a key enzyme involved in folate metabolism. Individuals carrying the high-risk TT genotype typically exhibit lower folate levels throughout life.
The study revealed that TT carriers with low Mankai consumption experienced an increase in cardiovascular risk according to the Framingham Risk Score. In contrast, TT carriers with high adherence to the Mankai-enriched Green Mediterranean diet demonstrated a remarkable 7.74-point reduction in cardiovascular risk score, highlighting the potential interaction between dietary behavior and inherited metabolic susceptibility.
One of the study’s most striking discoveries emerged from transcriptomic analyses. In response to increased intake of plant-derived nutrients, cells from TT carriers appeared to undergo adaptive biological reprogramming. Blood mRNA analyses revealed significant enrichment and increased expression of alternative folate-pathway genes, including MTHFD2 and DHFR, which compensated for reduced inherited enzyme activity and enabled more efficient utilization of dietary folate.
These findings provide a mechanistic explanation for a series of previously reported clinical outcomes from the internationally recognized DIRECT-PLUS trial, one of the world's most comprehensive and rigorously controlled nutrition and imaging studies. Folate serves as a central component of one-carbon metabolism, driving methylation processes that act as an “epigenetic pencil” capable of influencing inflammatory and protective cellular pathways without altering the DNA sequence itself.
The newly identified molecular axis helps explain previously observed benefits of the Green Mediterranean diet across multiple organ systems. Earlier analyses from the DIRECT-PLUS study demonstrated regression of carotid atherosclerosis, reductions in aortic stiffness, improvements in glycemic control, reductions in visceral adiposity and liver fat, and favorable effects on biomarkers associated with brain aging. Together, these findings suggest that targeted nutritional interventions may influence biological pathways involved in cardiometabolic health and healthy aging.
At the center of this metabolic transformation stands Mankai, a nutrient-dense aquatic plant containing more than 45% protein, essential amino acids, fiber, minerals, and naturally occurring folate. Mankai is particularly rich in bioavailable folate and provides a substantial proportion of the recommended daily intake. Participants with the highest Mankai intake exhibited the strongest folate response and the most pronounced transcriptomic and clinical changes, suggesting that Mankai may play a central role in driving the biological effects observed during the intervention.
A key contribution to the study came from researchers at Leipzig University, Leipzig Center of Metabolism (LieCeM), who led major components of the molecular and genetic analyses. Dr. Maria Keller and Prof. Peter Kovacs co-directed the nutrigenomic and transcriptomic investigations that enabled the team to identify genotype-specific responses to the Green Mediterranean diet and to characterize the folate-dependent mechanisms underlying its health benefits.
Prof. Iris Shai, principal investigator of the study, of Ben-Gurion University of the Negev, Dean of Sustainability at Reichman University, Adjunct Professor at Harvard University, and Honorary Professor at Leipzig University, said: “Our findings show that a diet rich in green plant-based foods may influence folate-related metabolic pathways associated with cardiometabolic health. The relationship we observed between folate levels, visceral fat reduction, and genetic responsiveness strengthens the scientific basis for personalized nutrition and advances the field of Nutri-Omics. These results suggest that folate may be considered not only a marker of deficiency, but also a biomarker reflecting dietary quality, cellular metabolic status, and the body’s capacity to activate protective metabolic and epigenetic mechanisms.”
Dr. Hila Zelicha Peer, first author of the study, from Ben-Gurion University of the Negev and currently a postdoctoral fellow, David Geffen School of Medicine at UCLA, said:
“Until now, folate has primarily been viewed through the lens of nutritional deficiency. Our findings suggest a broader role as a metabolic biomarker that reflects both the quality of plant-based nutrition and the body's response to dietary intervention. The transcriptomic discoveries demonstrate that highly bioavailable plant-derived foods such as Mankai may directly influence cellular adaptability, help compensate for inherited metabolic challenges, and support long-term health.”
The international research team also included Dr. Anat Yaskolka Meir, Dr. Ehud Rinott, Dr. Gal Tsaban, and Dr. Alon Kaplan from Ben-Gurion University of the Negev; Dr. Anne Hoffmann, Prof. Matthias Blüher, Prof. Uta Ceglarek, Prof. Berend Isermann, and Prof. Michael Stumvoll from Leipzig University and the Helmholtz Institute in Germany; Prof. Ilan Shelef from Soroka University Medical Center; and Prof. Frank Hu and Prof. Meir Stampfer from Harvard University.
This work was supported by grants from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany's Excellence Strategy – EXC-3105/1–533765739; Israel Ministry of Health grant 87472511; Israel Ministry of Science and Technology grant 3-13604, and the California Walnuts Commission.
