Lactate Has Been Identified as Key Metabolic Regulator
New research in rats suggests lactate plays a critical role in how the liver regulates fat breakdown during exercise.
Updated on Oct. 3, 2026 in Nutrition
Researchers have discovered that lactate functions as a signaling molecule to trigger the release of the hormone FGF21 during physical activity. This process appears to be a key component in how the body mobilizes fat stores for energy during exertion.
Why it matters
Understanding this metabolic pathway provides new insight into how exercise drives fat metabolism at a molecular level. By identifying lactate as a mediator of FGF21, scientists are better mapping the complex communication between muscles, the liver, and adipose tissue during movement.
This study used a controlled experiment with male Wistar rats to evaluate the role of lactate in FGF21 signaling. Findings showed that lactate administration stimulated hepatic FGF21 and p-AMPK levels, while reducing hyperlactatemia dampened the exercise-induced FGF21 response.
The details
During exercise, muscles produce lactate, which the study suggests travels to the liver to initiate the expression of the hormone FGF21. This hormone then acts on subcutaneous fat tissue by upregulating specific receptors, such as FGFR1 and beta-Klotho, which work together to facilitate lipolysis, or the breakdown of fats. The study demonstrated this relationship by using dichloroacetate to artificially lower lactate levels, which consequently reduced the expected rise in FGF21 and disrupted this metabolic signaling chain.
Timeline
October 3, 2026: The research findings were formally published.
Health Landscape
This study advances our mapping of the FGF21 metabolic signaling pathway, which is currently a major focus of endocrine and metabolic research. It provides new context for the hormonal regulation of energy metabolism that occurs during physical activity.
While this study helps explain the complex biology of fat burning during exercise, it does not change current recommendations for physical activity. If you have questions about how your exercise habits might influence your metabolic health, discuss them with your physician.
The takeaway
This study underscores that exercise is a sophisticated chemical process involving organs far beyond the muscles. A consistent exercise routine remains the best evidence-based habit for supporting healthy metabolic signaling in the body.
Further reading
For more on the biological mechanisms that connect dietary and exercise patterns to systemic health, visit our Nutrition section.
More information
You can review the full findings in the peer-reviewed research article.
Source note: This article includes information reported by Nature.
