Evidence Review
Phytochemical Profile and Anti-Inflammatory Mechanisms
Sharma et al. (2023) conducted a comprehensive review of chrysanthemum's phytochemistry and pharmacology [1]. The dominant flavonoids — luteolin, apigenin, and acacetin — are present primarily as 7-O-glucosides. Upon consumption, intestinal bacteria and gut mucosal enzymes hydrolyze these glycosides, releasing the aglycone forms with higher anti-inflammatory potency and membrane permeability.
The anti-inflammatory mechanisms documented for these compounds include:
- Inhibition of NF-κB nuclear translocation, suppressing transcription of pro-inflammatory cytokines
- Downregulation of COX-2 and inducible nitric oxide synthase (iNOS)
- Scavenging of reactive oxygen species via direct antioxidant activity
- Modulation of MAPK signaling pathways (p38 and JNK)
Adenosine — present in measurable quantities in brewed chrysanthemum tea — contributes independently to vasodilation through A2 receptor activation, providing a non-flavonoid mechanism for the tea's cardiovascular effects [1].
Li et al. (2019) — Chemical Analysis of Commercial Teas
Li et al. analyzed seventeen commercial chrysanthemum teas including hangbaiju, gongju, huaiju, Snow chrysanthemum, and Coreopsis tinctoria (a common adulterant) [2]. Using UPLC/Q-TOF-MS, they identified 6,8-C,C-diglucosylapigenin and eriodictyol-7-O-glucoside for the first time in Snow chrysanthemum, and acetylmarein in several traditional varieties.
Key anti-inflammatory findings: all hot-water extracts suppressed LPS-induced IL-6, IL-1β, and COX-2 mRNA expression in RAW 264.7 macrophages. The Snow chrysanthemum extract, enriched in anthocyanins, showed the highest DPPH radical scavenging activity (ORAC value: 1222.50 μmol Trolox equivalents/g), substantially outperforming some varieties of green tea in this assay.
Gao et al. (2016) — Hypertension and Cardiac Hypertrophy
This study used spontaneously hypertensive rats treated with C. morifolium extract over 12 weeks [3]. Treated animals showed significant reductions in systolic blood pressure compared to controls, along with decreased left ventricular hypertrophy (measured by heart weight-to-body-weight ratio and posterior wall thickness). Mechanistically, the extract inhibited myocardial HIF-1α expression — a transcription factor activated by chronic hypertension that drives pathological cardiac remodeling. The researchers attributed the blood pressure effects primarily to the vasodilatory activity of adenosine and luteolin in the extract.
Limitations: rodent model only; no human clinical trial has directly evaluated chrysanthemum extract for hypertension in a controlled design.
Lii et al. (2010) — Cardiovascular Protection
Lii et al. investigated whether C. morifolium extracts could suppress the adhesion molecule expression that initiates atherosclerosis [4]. Oxidized LDL-treated human endothelial cells showed strongly upregulated ICAM-1 and E-selectin — both markers of early atherosclerotic endothelial activation. Treatment with the chrysanthemum hot-water extract, the ethanol extract, or isolated luteolin/apigenin dose-dependently inhibited this expression. The mechanism involved PI3K/Akt pathway modulation and antioxidant activity.
The effect sizes were substantial (>50% inhibition at tested concentrations), suggesting that the flavonoids achieve biologically relevant concentrations in endothelial tissue. However, ex vivo cell studies do not directly translate to in vivo outcomes without supporting pharmacokinetic data.
Jeong et al. (2013) — Liver Protection
In a CCl4-induced liver toxicity model, Jeong et al. showed that hot water extract of C. indicum flower significantly reduced serum GOT and GPT (markers of liver cell damage) by 60.1% and 64.5% respectively compared to vehicle controls [5]. The extract also improved survival of HepG2 (human hepatoma) and Chang (normal hepatic) cell lines treated with hepatotoxins. The proposed mechanism was inhibition of CYP2E1, a cytochrome P450 enzyme that bioactivates CCl4 into toxic radicals.
This study used the C. indicum species (wild chrysanthemum), which is botanically distinct from the cultivated C. morifolium used for tea in China. While both species share overlapping phytochemical profiles, the extent to which results translate between species requires further investigation.
Overall Assessment
The evidence for chrysanthemum tea is strongest for anti-inflammatory activity (multiple in vitro studies with consistent results) and mechanistically plausible for cardiovascular support and liver protection. Eye health benefits are supported by traditional use and theoretical antioxidant mechanisms but lack dedicated clinical trial evidence. The tea is exceptionally safe — no significant adverse effects have been documented in the literature, and its long history of use by hundreds of millions of people provides substantial real-world safety evidence. People with chrysanthemum pollen allergies should exercise caution.