Metabolic & Cardiometabolic · Gut & Microbiome

gut-microbiota-derived D-lactate worsens glucose metabolism

In plain terms: Does D-lactate made by gut bacteria worsen blood sugar control?

Insufficient Metabolic & Cardiometabolic 🐭 Non-human evidence🔬 Includes disconfirming

RefutedContestedStrong support

consensus score 0.46

⚖️ Thin evidence — read the needle loosely. The score shows which way the studies lean, but there are too few independent, high-quality ones to place it firmly. Expect this to move as better evidence arrives.

In obese mice, microbe-made D-lactate raised blood glucose and trapping it improved glucose, insulin and fatty-liver disease, but this is animal-stage evidence not yet shown in humans.

📅 Last reviewed: 2026-07-14 ⓘ

Evidence ladder

How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."

Top evidence so far: Animal studies (Animal)

MechanismIn-vitroAnimalObservationalRCTMeta-analysis

How the studies fall

1 support 0 contradict 3 tested null 0 mixed · 4 sources, 1 independent group

What the evidence shows

In obese mice, microbe-made D-lactate raised hepatic glucose production and a gut D-lactate trap improved glucose and insulin, and D-lactate is higher in obese humans. The human side is all corroborating context rather than test: microbiota composition drives circulating levels and a metabolising-enzyme defect raises them, but nobody has shown lowering it helps people.

The evidence (4)

Source	Grade	Stance	Quality	Finding
Fang H, Anhê FF, Zada DK, Barra NG, E-Lacerda RR, McAlpin BT, Wylie R, Berthiaume L, Audet-Walsh É, O'Dwyer C, Ghorbani P, Fullerton MD, Gagnon C, Tchernof A, Marette A, Schertzer JD 2025 · Cell Metab	animal	supports	high	Source paper: D-lactate higher in obese humans/mice; raised hepatic glucose; gut "D-lactate trap" polymer lowered glucose+insulin & MASH fibrosis in obese mice.
Busing JD, Fouladi F, Bulik-Sullivan EC, Carroll IM, Fodor AA, Thomsen KF, Gulati AS, Nicholson MR 2023 · J Pediatr Gastroenterol Nutr	observational	tested-null	low	Independent: gut microbiota composition drives circulating D-lactate (FMT alters it), corroborating microbial origin but not the glucose-dysregulation step.
Monroe GR, van Eerde AM, Tessadori F, Duran KJ, Savelberg SMC, van Alfen JC, Terhal PA, van der Crabben SN, Lichtenbelt KD, Fuchs SA, Gerrits J, van Roosmalen MJ, van Gassen KL, van Aalderen M, Koot BG, Oostendorp M, Duran M, Visser G, de Koning TJ, Calì F, Bosco P, Geleijns K, de Sain-van der Velden MGM, Knoers NV, Bakkers J, Verhoeven-Duif NM, van Haaften G, Jans JJ 2019 · Nat Commun	mechanism	tested-null	low	Independent: LDHD loss-of-function raises human D-lactate, confirming a dedicated D-lactate metabolic pathway in humans (mechanistic plausibility).
Jain A, Jhinger K, Bellas J 2021 · Case Rep Gastroenterol	observational	tested-null	low	Independent: clinical D-lactic acidosis ties high carbohydrate load + microbial D-lactate to systemic effects, but neurologic not glycemic; supports source not glucose.

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