Myricetin

Human data concern blends. In the Blueberin trial, 42 women with type 2 diabetes were randomized to placebo or three daily tablets containing blueberry leaf extract and myricetin for four weeks, alongside a controlled 1700-kcal diet. Fasting glucose, CRP and liver enzymes fell in the active group. The paper reports glucose units as mg/L despite values that appear inconsistent with that unit; no corrected absolute glucose values are presented here. A significant within-group change in one arm and a nonsignificant change in the other do not by themselves establish a between-group treatment effect [3].

Emulin was tested in 40 adults with diabetes for one week. Some glucose measures improved, especially in the metformin-plus-blend group, but isolated myricetin was not tested [4].

A 2024 single-blind pilot in 20 young adults tested a silymarin/PQQ/myricetin-containing product after red wine. The full-text table reports blood ethanol of 0.015 versus 0.020 g/L at 120 minutes, about 25% lower in the active group relative to placebo; the abstract's 33% figure instead corresponds to placebo being higher relative to the active group. Urinary ethyl glucuronide and the primary plasma ROS measure did not differ significantly between groups. CoQ10 and several other markers were also unchanged. This small blend study does not establish an alcohol-clearance effect of myricetin alone or reduced intoxication [5].

The clearer efficacy signals are in animals. A 2017 study gave male mice 50 mg/kg/day orally for three weeks and reported roughly twice the treadmill time and distance to exhaustion, with ten mice per group. Muscle and brown-fat mitochondrial measures improved, but body weight and food intake were unchanged; liver citrate synthase activity did not increase [6].

A 2024 meta-analysis pooled 21 studies involving 514 mice with metabolic disease models. Glucose, insulin, triglycerides, total cholesterol and LDL were lower overall, while the pooled HDL effect was not significant. Heterogeneity was substantial, reporting of randomization and blinding was weak, and publication-bias analyses suggested benefits could be overestimated. This is an animal meta-analysis, not clinical confirmation [2].

In a 2025 study, female 3xTg Alzheimer's-model mice given 50 mg/kg/day showed better object recognition and water-maze performance, fewer amyloid plaques and lower phosphorylated tau and neuroinflammatory markers. Behavioral groups contained ten mice; the human component was analysis of existing single-cell sequencing data, not a trial administering myricetin to patients [7].

Myricetin has several experimentally described actions. Its phenolic groups support radical-scavenging and metal-chelating chemistry, but it can also promote oxidation under some assay conditions. Antioxidant activity in a test tube does not establish a net clinical benefit [1].

In mouse muscle, increased SIRT1 expression, NAD-related changes and reduced PGC-1α acetylation accompanied mitochondrial biogenesis. SIRT1 knockdown attenuated the cell response, and the lifespan effect in worms was lost in a sir-2.1 mutant. These experiments support a SIRT1-dependent pathway; they do not establish myricetin as a directly binding SIRT1 agonist or show lifespan extension in humans [6].

Direct biochemical evidence includes inhibition of PDI and ERp5, enzymes involved in platelet function. Human blood exposed to myricetin in vitro formed fewer thrombi on collagen, but platelet spreading on fibrinogen was unaffected and ERp57/ERp72 reductase activity was not inhibited [8].

The Alzheimer's-model study measured binding to RORγt and interference with its interaction with the IL17 promoter. Lower Th17 polarization and IL-17 production offer a mechanistic explanation for the mouse neuroinflammation findings; human target engagement remains untested [7].

Plain myricetin is poorly water-soluble, and the rat PK experiment found low oral availability. The reviewed formulation literature treats poor absorption and stability as obstacles to development. Improved delivery cannot be assumed to confer a human clinical benefit or to share the safety of ordinary dietary exposure [1][2][9].

Short studies provide some reassuring observations. All Blueberin participants completed four weeks and the authors reported no indication of adverse toxic effects, but that was a blend study [3]. The one-week Emulin study reported gastrointestinal issues in one participant in each metformin-containing arm, with no attribution to myricetin [4]. The alcohol pilot had no dropouts and no significant changes in its measured liver laboratory parameters over one week [5]. These studies do not establish the long-term safety of isolated myricetin.

In the endurance experiment, 50 mg/kg/day for three weeks produced no reported overt toxicity or changes in the assessed liver/kidney histology and serum measures; the methods describe histology from only one mouse per group [6]. In a separate experiment, 25 or 50 mg/kg orally for three days did not prolong mouse tail-bleeding time despite the strong in vitro antiplatelet findings [8].

High-concentration cell experiments are less reassuring: the review reports injury to isolated guinea-pig intestinal cells at 450 µM and pro-oxidant effects in particular metal-containing assay systems. These are toxicity signals in experimental systems, not demonstrated adverse-event rates in supplement users [1].

In rats, coadministration of myricetin increased exposure to oral losartan. Parallel laboratory assays showed inhibition of CYP3A4, CYP2C9 and P-glycoprotein. This is a potential drug-interaction signal; its magnitude at human supplement doses is unknown [10].

Additive effects with antiplatelet or anticoagulant medicines are a mechanism-based concern inferred from the platelet assays, not a documented clinical interaction. The same study's mouse bleeding-time result was null [8]. Similarly, glucose-lowering combinations deserve caution because myricetin-containing blends changed glucose measures, but these trials do not establish a standalone myricetin interaction [3][4].