A diet rich in medium-chain triglycerides (MCTs) raised ghrelin levels 2.5-fold in mice but paradoxically blocked ghrelin's appetite-stimulating effect, suggesting MCTs interfere with ghrelin signaling upstream of the hunger pathway.
2.5× ghrelin, 0 appetiteMCT diet raised ghrelin levels 2.5-fold but completely blocked its ability to stimulate food intake, revealing a dietary disconnect between ghrelin levels and hunger.
What the researchers found
MCT diet feeding raised plasma ghrelin 2.5-fold but completely blocked ghrelin-induced food intake and hypothalamic NPY upregulation, while leaving ghrelin-induced growth hormone secretion intact.
Why it matters
Understanding how dietary fats modulate ghrelin signaling could lead to dietary strategies that naturally suppress hunger without blocking ghrelin's beneficial growth hormone effects — a more targeted approach than blanket ghrelin-blocking drugs.
The numbers in context
No specific numerical outcomes detailed in abstract; study measured food intake and body weight changes in MCT-fed versus control mice.
How the study worked
Mouse study comparing MCT vs LCT diets over 5 days, using wild-type mice, ghrelin transgenic mice, and ghrelin/GOAT double transgenic mice. Measured plasma ghrelin, food intake, body weight, hypothalamic NPY expression, and growth hormone secretion.
Who was studied
Mice (ghrelin transgenic and ghrelin-treated)
What this study cannot tell us
This is a mouse study and may not directly translate to humans. The 5-day MCT feeding period is short, and long-term effects are unknown. The mechanism by which MCTs block ghrelin's orexigenic signaling upstream of NPY remains unclear. MCT doses used may not reflect typical human dietary intake.
How to read the evidence
This is a well-designed animal study using multiple mouse models (wild-type, transgenic, double transgenic) with clear controls. However, as a mouse study it is preliminary evidence for human applicability.
When this study was published
Published in 2025, representing current research on the interplay between dietary lipids and peptide hormone signaling.
The bigger picture
Ghrelin has been a challenging drug target because blocking it affects both appetite and growth hormone pathways. This study reveals that MCTs can selectively disable ghrelin's hunger signal while preserving its growth hormone function — a natural selectivity that pharmaceuticals have struggled to achieve.
Questions still open
- Do MCTs have a similar ghrelin-blocking appetite effect in humans?
- What is the specific molecular mechanism by which MCTs interfere with ghrelin signaling upstream of NPY?
- Could MCT supplementation enhance the effectiveness of GLP-1-based weight loss therapies?
Common questions
Does MCT oil suppress appetite by blocking ghrelin?
Is this why coconut oil is linked to appetite control?
Read the original research
Dietary medium chain triglycerides impairs orexigenic action of ghrelin in mice.
Frontiers in endocrinology, 16, 1690761
Citation
Aotani, Daisuke; Ariyasu, Hiroyuki; Tanaka, Tomohiro; Shimazu-Kuwahara, Satoko; Nomura, Hidenari; Shimizu, Yoshiyuki; Takeda, Katsushi; Koyama, Hiroyuki; Kusakabe, Toru; Miyazawa, Takashi; Hikida, Takatoshi; Kataoka, Hiromi; Nakao, Kazuwa. (2025). Dietary medium chain triglycerides impairs orexigenic action of ghrelin in mice.. Frontiers in endocrinology, 16, 1690761. https://doi.org/10.3389/fendo.2025.1690761