Dietary Fat Type 1,3-DAG Boosts GLP-1 and PYY Through Gut Bacteria in Diabetic Rats | Research

The takeaway

1,3-Diacylglycerol improved blood sugar and lipid levels in diabetic rats by reshaping gut bacteria to produce more short-chain fatty acids, which activated GPR41 signaling to increase GLP-1 and PYY peptide secretion.

GLP-1 and PYY both increased
Dietary 1,3-DAG boosted endogenous production of these metabolic peptide hormones through gut microbiota remodeling and SCFA-GPR41 signaling in diabetic rats

What the researchers found

Both low-dose (50% DAG) and high-dose (100% DAG) 1,3-diacylglycerol significantly reduced fasting blood glucose, insulin, and triglycerides in T2DM rats to near-control levels over 8 weeks. 1,3-DAG restored colonic morphology, increased GPR41 receptor expression, and elevated GLP-1 and PYY secretion while reducing serum lipopolysaccharide (a marker of gut barrier leakage).

Gut microbiota analysis showed enrichment of Bacteroidota and depletion of Proteobacteria, with increased short-chain fatty acids (acetate, propionate, valerate). Bacteroidota taxa negatively correlated with blood sugar and lipid markers, while Proteobacteria positively correlated with LDL-C. The benefits appear mediated through a gut microbiota → SCFA → GPR41 → GLP-1 signaling axis.

Why it matters

GLP-1 and PYY are peptide hormones central to blood sugar and appetite regulation. While drugs like semaglutide provide these hormones externally, this study shows a dietary intervention that naturally boosts the body's own production of these peptides through the gut microbiome. This could offer an accessible, food-based complementary approach to diabetes management.

How the study worked

Male Wistar rats were fed a high-fat, high-sugar diet with weekly STZ injections (30 mg/kg) for 4 weeks to induce T2DM. After confirming stable hyperglycemia, rats were randomized to: healthy control, T2DM model, low-dose 1,3-DAG (50% DAG + 50% TAG), and high-dose 1,3-DAG (100% DAG) for 8 weeks. Outcomes included fasting glucose, insulin, lipids, colonic histology, GPR41 expression, GLP-1, PYY, serum LPS, 16S microbiota sequencing, and fecal SCFA levels by GC.

What this study cannot tell us

This is an animal study using a chemical (STZ) diabetes model that may not fully replicate human type 2 diabetes. Specific group sizes were not stated in the abstract. The 8-week duration is relatively short. The causal pathway (microbiota → SCFA → GPR41 → GLP-1) is correlative in this study — direct causation would require microbiota transfer or GPR41 knockout experiments. Human studies are needed to confirm whether dietary 1,3-DAG produces similar effects.

How to read the evidence

This is a preclinical animal study published in Food & Function. The mechanistic pathway is well-supported by multiple complementary measurements, but all findings are in rats and require human validation.

When this study was published

Published in 2026, this is a very recent study at the intersection of dietary fat research, gut microbiome science, and peptide hormone biology.

The bigger picture

The gut microbiome's role in metabolic health is a rapidly expanding field. This study connects dietary fat composition to endogenous peptide hormone production through a clear mechanistic pathway: 1,3-DAG → beneficial gut bacteria → short-chain fatty acids → GPR41 receptor activation → GLP-1/PYY release. As interest grows in food-as-medicine approaches to diabetes, understanding how specific dietary components affect peptide hormone signaling could transform nutritional recommendations.

Questions still open

Would dietary 1,3-DAG supplementation increase GLP-1 levels enough to produce clinically meaningful benefits in humans with type 2 diabetes?
Could 1,3-DAG be used as a dietary complement to GLP-1 receptor agonist medications to enhance their effects?
How does the microbiome-GLP-1 pathway activated by 1,3-DAG compare quantitatively to the direct GLP-1 elevation from injectable GLP-1 agonists?

Common questions

What is 1,3-DAG and where is it found in food?

1,3-Diacylglycerol (1,3-DAG) is a type of fat molecule found naturally in small amounts in various cooking oils. It's structurally different from the more common triglycerides that make up most dietary fat. Cooking oils enriched with DAG have been marketed in Japan for their health benefits, particularly for reducing body fat.

How does a dietary fat end up increasing GLP-1 levels?

1,3-DAG changes the types of bacteria living in the gut, favoring species that produce short-chain fatty acids (SCFAs) from fiber. These SCFAs activate GPR41 receptors on gut cells, which triggers the release of GLP-1 and PYY — the same hormones that drugs like semaglutide mimic. It's an indirect but natural pathway from dietary fat to metabolic hormone production.

Read the original research

Metabolic benefits of 1,3-diacylglycerol in type 2 diabetes mellitus and its association with gut microbiota-derived SCFAs-GPR41-GLP-1 signaling.

Food & function, 17(2), 734-749

View on PubMed ↗Publisher’s paper ↗

Citation

Li, Jiaomei; Wang, Hao; Yang, Jiekai; Wang, Yicheng; Jia, Guo; Gu, Jiaojiao. (2026). Metabolic benefits of 1,3-diacylglycerol in type 2 diabetes mellitus and its association with gut microbiota-derived SCFAs-GPR41-GLP-1 signaling.. Food & function, 17(2), 734-749. https://doi.org/10.1039/d5fo03164h