Astragalus

The strongest human signal is as an adjunct to chemotherapy, not as a standalone anticancer agent. A 2006 meta-analysis in the Journal of Clinical Oncology pooled 34 randomised trials (2,815 patients) of astragalus-based Chinese herbal medicine added to platinum chemotherapy for advanced non-small-cell lung cancer, and reported a reduced risk of death at 12 months (RR 0.67, 95% CI 0.52–0.87) and improved tumour response (RR 1.34, 95% CI 1.24–1.46) ^{1Reference 1McCulloch et al. · 2006Meta-analysisAstragalus-based Chinese herbs and platinum-based chemotherapy for advanced non-small-cell lung cancer — meta-analysis of randomized trialsView study →}. Later meta-analyses of astragalus injection and of astragalus-containing patent injections such as Kangai reproduce the direction — higher objective response and performance status, lower haematological toxicity — but again in Chinese-only RCTs of injectable or multi-herb products ^{2,3Reference 2Cao et al. · 2019Meta-analysisEvidence of Astragalus injection combined with platinum-based chemotherapy in advanced non-small cell lung cancer — a systematic review and meta-analysisView study →Reference 3Zhu et al. · 2022Meta-analysisEffect of Kangai injection combined with platinum-based chemotherapy on immune function in advanced NSCLC — a meta-analysisView study →}. Mechanistically this is plausibly immune-mediated: astragalus stimulates macrophage and NK-cell activity and shifts cytokine balance ^{1,12Reference 1McCulloch et al. · 2006Meta-analysisAstragalus-based Chinese herbs and platinum-based chemotherapy for advanced non-small-cell lung cancer — meta-analysis of randomized trialsView study →Reference 12Li et al. · 2022ReviewAstragalus polysaccharide: a review of its immunomodulatory effectView study →}.

Gap: every pooled trial is low-quality, unblinded, injection- or formula-based, and conducted in China with high publication-bias risk; no rigorous Western RCT of the oral root exists, and the JCO authors themselves called for confirmatory trials ^{1Reference 1McCulloch et al. · 2006Meta-analysisAstragalus-based Chinese herbs and platinum-based chemotherapy for advanced non-small-cell lung cancer — meta-analysis of randomized trialsView study →}.

Diabetic nephropathy is the best-replicated non-oncology use. A 2011 meta-analysis (25 trials, 1,804 patients) found astragalus injection improved renal-function surrogates (BUN, serum creatinine, creatinine clearance, urinary protein) and serum albumin versus controls ^{4Reference 4Li et al. · 2011Meta-analysisMeta-analysis of the clinical value of Astragalus membranaceus in diabetic nephropathy — randomized/controlled trialsView study →}. A 2024 meta-analysis (32 RCTs, 2,462 patients) of astragalus added to renin–angiotensin–aldosterone-system (RAAS) blockers in stage III disease reported a higher total effective rate and reduced urinary protein, creatinine, BUN and HbA1c ^{5Reference 5Lin et al. · 2024Meta-analysisEfficacy of astragalus combined with RAAS blockers in stage III diabetic nephropathy — a systematic review and meta-analysis of randomized controlled trialsView study →}. A 2014 Cochrane review of astragalus for chronic kidney disease (22 studies, 1,323 participants) found reduced proteinuria and raised haemoglobin and albumin — but flagged that hard endpoints (dialysis, mortality) were never reported and study quality was low overall ^{6Reference 6Zhang et al. · 2014Systematic reviewAstragalus (a traditional Chinese medicine) for treating chronic kidney disease — Cochrane systematic review of randomised controlled trialsView study →}. Animal work supports an antioxidant, anti-fibrotic renal mechanism ^{7Reference 7Zhang et al. · 2009Systematic reviewSystematic review of the renal protective effect of Astragalus membranaceus on diabetic nephropathy in animal modelsView study →}.

Gap: benefits are on surrogate markers only; no trial reported progression to dialysis or death, heterogeneity is high, and most protocols pair injectable astragalus with standard drugs rather than testing the root alone ^{6Reference 6Zhang et al. · 2014Systematic reviewAstragalus (a traditional Chinese medicine) for treating chronic kidney disease — Cochrane systematic review of randomised controlled trialsView study →}.

Astragalus injection added to conventional care for viral myocarditis has been synthesised repeatedly. A 2014 systematic review (6 RCTs, 639 patients) reported higher overall efficacy and better recovery of myocardial-enzyme and ECG measures, but two trials only reported adverse events and safety remained uncertain ^{8Reference 8Piao et al. · 2014Systematic reviewAstragalus membranaceus injection combined with conventional treatment for viral myocarditis — a systematic review of randomized controlled trialsView study →}. A 2022 meta-analysis (19 RCTs) found astragalus injection markedly lowered pro-inflammatory TNF-α (SMD −2.27), consistent with an immunomodulatory mechanism ^{9Reference 9Guo et al. · 2022Meta-analysisEffect of Astragalus injection on inflammatory mediators in patients with viral myocarditis — a systematic review and meta-analysisView study →}. A 2020 clinical-and-preclinical systematic review (28 clinical studies, 2,522 participants; 16 animal studies) found reduced cardiac troponin I and myocardial enzymes but scored trial quality low (mean ~3.3/7) ^{10Reference 10Zheng et al. · 2020Systematic reviewClinical and preclinical systematic review of Astragalus membranaceus for viral myocarditisView study →}.

Gap: uniformly low methodological quality, small samples, injectable form, and high publication-bias risk; conclusions are provisional pending large rigorous RCTs ^{8,10Reference 8Piao et al. · 2014Systematic reviewAstragalus membranaceus injection combined with conventional treatment for viral myocarditis — a systematic review of randomized controlled trialsView study →Reference 10Zheng et al. · 2020Systematic reviewClinical and preclinical systematic review of Astragalus membranaceus for viral myocarditisView study →}.

This is the herb’s traditional headline and its preclinical strength — but the flagship human claim is unproven. Astragalus polysaccharide activates macrophages, NK cells, dendritic cells and T and B lymphocytes and induces a broad cytokine response across in-vitro and animal models ^{12Reference 12Li et al. · 2022ReviewAstragalus polysaccharide: a review of its immunomodulatory effectView study →}. Yet a 2016 Cochrane review searching for RCTs of oral astragalus as a sole agent to prevent recurrent respiratory infections in children found that, of 6,080 records, no trial met inclusion criteria — leaving the “prevents colds/flu” claim without qualifying evidence ^{11Reference 11Su et al. · 2016Systematic reviewOral Astragalus (Huang qi) for preventing frequent episodes of acute respiratory tract infection in children — Cochrane systematic reviewView study →}. The one placebo-controlled human trial in this space (seasonal allergic rhinitis, n=48, 6 weeks) tested a herbal-mineral complex in which astragalus is the active, and only rhinorrhoea reached significance on the primary endpoints — a mixed, not positive, result ^{13Reference 13Matkovic et al. · 2010RCTEfficacy and safety of Astragalus membranaceus in the treatment of patients with seasonal allergic rhinitis — a double-blind, placebo-controlled randomized trialView study →}.

Gap: no placebo-controlled RCT of the whole root for infection prevention or immune modulation; the human immune data that exist come from combination products or from oncology-adjunct trials, not from astragalus taken as a daily immune tonic ^{11,13Reference 11Su et al. · 2016Systematic reviewOral Astragalus (Huang qi) for preventing frequent episodes of acute respiratory tract infection in children — Cochrane systematic reviewView study →Reference 13Matkovic et al. · 2010RCTEfficacy and safety of Astragalus membranaceus in the treatment of patients with seasonal allergic rhinitis — a double-blind, placebo-controlled randomized trialView study →}.

A 2011 dose-ranging RCT (n=90) gave astragalus granule at three doses alongside perindopril for chronic heart failure and found dose-dependent improvements in left-ventricular ejection fraction and 6-minute walk distance, with the high and moderate doses outperforming the low dose ^{14Reference 14Yang et al. · 2011RCTClinical effect of Astragalus granule of different dosages on quality of life in patients with chronic heart failure — a randomized controlled trialView study →}. The mechanistic base is substantial but preclinical: astragaloside IV reduces infarct size and improves post-ischaemic function in animal ischaemia/reperfusion models, acting through calcium-sensing-receptor and ERK-linked anti-apoptotic pathways ^{15,16,17Reference 15Zheng et al. · 2018Meta-analysisA preclinical systematic review and meta-analysis of astragaloside IV for myocardial ischemia/reperfusion injury (animal models)View study →Reference 16Zhang et al. · 2006In vitroAstragaloside IV from Astragalus membranaceus shows cardioprotection during myocardial ischemia in vivo and in vitroView study →Reference 17Yin et al. · 2019AnimalAstragaloside IV attenuates myocardial ischemia/reperfusion injury in rats via inhibition of calcium-sensing-receptor-mediated apoptotic signalingView study →}, and a preclinical meta-analysis pooled this ischaemia/reperfusion signal ^{15Reference 15Zheng et al. · 2018Meta-analysisA preclinical systematic review and meta-analysis of astragaloside IV for myocardial ischemia/reperfusion injury (animal models)View study →}.

Gap: human trials are small, short and use combination regimens on top of ACE inhibitors, so astragalus’s independent contribution is hard to isolate; the strong cardioprotective data are almost entirely animal or isolated-constituent ^{14,15Reference 14Yang et al. · 2011RCTClinical effect of Astragalus granule of different dosages on quality of life in patients with chronic heart failure — a randomized controlled trialView study →Reference 15Zheng et al. · 2018Meta-analysisA preclinical systematic review and meta-analysis of astragaloside IV for myocardial ischemia/reperfusion injury (animal models)View study →}.

Antioxidant activity underpins several of the other indications and is well-replicated preclinically. Astragaloside IV and astragalus polysaccharide reduce reactive oxygen species and lipid peroxidation and up-regulate the Nrf2/HO-1 cytoprotective pathway in endothelial and other cell models ^{18,28Reference 18Zhang et al. · 2020ReviewAstragaloside IV derived from Astragalus membranaceus — a research review on the pharmacological effectsView study →Reference 28Wang et al. · 2021ReviewActivation of Nrf2/HO-1 signaling — an important molecular mechanism of herbal medicine in the treatment of atherosclerosis (review, includes astragalus constituents)View study →}. A 2022 systematic review and meta-analysis of animal ulcerative-colitis studies found astragalus polysaccharide consistently lowered oxidative-stress and inflammatory markers ^{19Reference 19Hu et al. · 2022Meta-analysisAnti-inflammatory and antioxidant activity of astragalus polysaccharide in ulcerative colitis — a systematic review and meta-analysis of animal studiesView study →}.

Gap: entirely in-vitro and animal — no human study measures an antioxidant endpoint after oral astragalus, and effects are largely attributed to isolated constituents rather than the whole root ^{18,19Reference 18Zhang et al. · 2020ReviewAstragaloside IV derived from Astragalus membranaceus — a research review on the pharmacological effectsView study →Reference 19Hu et al. · 2022Meta-analysisAnti-inflammatory and antioxidant activity of astragalus polysaccharide in ulcerative colitis — a systematic review and meta-analysis of animal studiesView study →}.

Astragaloside IV suppresses NF-κB signalling — often via TLR4 upstream — across a wide range of animal models, including neuroinflammation in Parkinson’s-model mice, glucocorticoid-induced bone loss, and hypoxic cardiac injury ^{7,18Reference 7Zhang et al. · 2009Systematic reviewSystematic review of the renal protective effect of Astragalus membranaceus on diabetic nephropathy in animal modelsView study →Reference 18Zhang et al. · 2020ReviewAstragaloside IV derived from Astragalus membranaceus — a research review on the pharmacological effectsView study →}. A meta-analysis of animal colitis studies links this to reduced tissue inflammatory mediators ^{19Reference 19Hu et al. · 2022Meta-analysisAnti-inflammatory and antioxidant activity of astragalus polysaccharide in ulcerative colitis — a systematic review and meta-analysis of animal studiesView study →}. The pathway is consistent and well-mapped, which is why anti-inflammatory action recurs as the shared mechanism behind the hepatoprotective, cardioprotective and renal-protective signals.

Gap: no human anti-inflammatory trial of astragalus; all data are animal or cell-based and centre on the isolated saponin rather than the root as consumed ^{18,19Reference 18Zhang et al. · 2020ReviewAstragaloside IV derived from Astragalus membranaceus — a research review on the pharmacological effectsView study →Reference 19Hu et al. · 2022Meta-analysisAnti-inflammatory and antioxidant activity of astragalus polysaccharide in ulcerative colitis — a systematic review and meta-analysis of animal studiesView study →}.

Preclinical liver-protection data are consistent. Astragaloside IV attenuates alcoholic liver injury in rats (lowering ALT/AST, inflammatory cytokines and oxidative markers) ^{20Reference 20Hao et al. · 2024AnimalMetabolomics combined with network pharmacology reveals the protective effect of astragaloside IV on alcoholic liver disease (rat model)View study →}; cycloastragenol reduces carbon-tetrachloride-induced fibrosis in mice ^{21Reference 21Luangmonkong et al. · 2023AnimalHepatoprotective efficacy of cycloastragenol alleviated the progression of liver fibrosis in carbon-tetrachloride-treated miceView study →}; and astragalus polysaccharide shows synergistic protection with Schisandra lignans against chronic chemical liver injury ^{22Reference 22Yan et al. · 2009AnimalSynergistic hepatoprotective effect of Schisandra lignans with Astragalus polysaccharides on chronic liver injury in ratsView study →}. The one human study is a 48-week RCT (n=92) in chronic hepatitis B liver fibrosis using an astragalus–Polygonum decoction, which improved serum fibrosis markers (HA, LN, PCIII, CIV) and liver function more than the comparator — but it tested a combination formula, not astragalus alone ^{29Reference 29Yin et al. · 2000RCTComparison of efficacy in treating liver fibrosis of chronic hepatitis B between Astragalus-Polygonum anti-fibrosis decoction and Jinshuibao capsule — a randomized controlled trialView study →}.

Gap: the human trial is a multi-herb decoction with an active-comparator (not placebo) design; standalone-root efficacy in liver disease is untested, and the strong data are animal/constituent-level ^{20,21Reference 20Hao et al. · 2024AnimalMetabolomics combined with network pharmacology reveals the protective effect of astragaloside IV on alcoholic liver disease (rat model)View study →Reference 21Luangmonkong et al. · 2023AnimalHepatoprotective efficacy of cycloastragenol alleviated the progression of liver fibrosis in carbon-tetrachloride-treated miceView study →}.

Astragalus is a component of many Chinese anti-diabetic formulas, and its polysaccharides, saponins and flavonoids show glucose-lowering and insulin-sensitising activity in preclinical models ^{23Reference 23Zhang et al. · 2015Systematic reviewBiological active ingredients of traditional Chinese herb Astragalus membranaceus on treatment of diabetes — a systematic reviewView study →}. In humans, however, the trial evidence concentrates on diabetic complications — chiefly nephropathy (see Renal protection) — rather than on glycaemic control itself, and animal renal-protection reviews note fasting-glucose reduction as a secondary effect ^{7,23Reference 7Zhang et al. · 2009Systematic reviewSystematic review of the renal protective effect of Astragalus membranaceus on diabetic nephropathy in animal modelsView study →Reference 23Zhang et al. · 2015Systematic reviewBiological active ingredients of traditional Chinese herb Astragalus membranaceus on treatment of diabetes — a systematic reviewView study →}.

Gap: no robust human RCT demonstrates that oral astragalus meaningfully lowers HbA1c or fasting glucose as a primary outcome; the antidiabetic case is largely mechanistic and constituent-based ^{23Reference 23Zhang et al. · 2015Systematic reviewBiological active ingredients of traditional Chinese herb Astragalus membranaceus on treatment of diabetes — a systematic reviewView study →}.

The traditional “tonic for vitality and stamina” use has thin trial support. A small 2002 RCT (12 athletes, 8 weeks) of Huangqi Jianzhong Tang — a combination formula in which astragalus is the lead herb — reported increased time-to-exhaustion and improved anaerobic threshold versus placebo ^{24Reference 24Chen et al. · 2002RCTReducing fatigue of athletes following oral administration of Huangqi Jianzhong Tang — a randomized placebo-controlled trialView study →}. Several registry trials target cancer-related fatigue using PG2, an astragalus-polysaccharide injection, rather than the oral herb.

Gap: the only published RCT is tiny and tests a multi-herb decoction, not astragalus root; there is no adequately powered trial of the whole herb for fatigue or exercise performance ^{24Reference 24Chen et al. · 2002RCTReducing fatigue of athletes following oral administration of Huangqi Jianzhong Tang — a randomized placebo-controlled trialView study →}.

A 2026 systematic review of astragalus as a skincare ingredient concluded its active compounds — astragaloside IV, cycloastragenol, flavonoids and polysaccharides — show photoprotective effects (ROS reduction, collagen promotion, telomere preservation) with some clinical improvements in hydration, tone and wrinkles ^{25Reference 25Jackson et al. · 2026Systematic reviewAstragalus membranaceus extract as a botanical ingredient for pigmentary and anti-aging skincare — a systematic reviewView study →}. Cell work supports this: cycloastragenol reduces UVB-induced matrix metalloproteinases and ROS and preserves collagen I in human dermal fibroblasts and keratinocytes ^{26Reference 26Yang et al. · 2023In vitroCycloastragenol exerts protective effects against UVB irradiation in human dermal fibroblasts and HaCaT keratinocytes (in vitro)View study →}.

Gap: this is a topical/cosmetic application of isolated constituents; it does not transfer to the oral dried root, and the clinical evidence within the review is limited and heterogeneous ^{25,26Reference 25Jackson et al. · 2026Systematic reviewAstragalus membranaceus extract as a botanical ingredient for pigmentary and anti-aging skincare — a systematic reviewView study →Reference 26Yang et al. · 2023In vitroCycloastragenol exerts protective effects against UVB irradiation in human dermal fibroblasts and HaCaT keratinocytes (in vitro)View study →}.

This was previously the page’s sole research entry and remains the thinnest indication. Cycloastragenol and astragaloside IV activate telomerase in vitro, and the commercial product TA-65 is derived from Astragalus membranaceus (not, as sometimes stated, a “related species”) ^{27Reference 27Canale et al. · 2025ReviewTargeting telomere shortening in vascular aging and atherosclerosis — therapeutic promise of cycloastragenol/astragaloside IV (review)View study →}. Interest centres on vascular ageing, where telomere dysfunction contributes to endothelial senescence ^{27Reference 27Canale et al. · 2025ReviewTargeting telomere shortening in vascular aging and atherosclerosis — therapeutic promise of cycloastragenol/astragaloside IV (review)View study →}. Human data are limited to small, largely industry-linked TA-65 trials (e.g. in metabolic syndrome) with surrogate endpoints.

Gap: telomerase activation is a cell-level finding; there is no rigorous human trial showing oral astragalus extends healthspan or lifespan, and pharmacological telomerase activation carries theoretical oncogenic concerns that remain unresolved ^{27Reference 27Canale et al. · 2025ReviewTargeting telomere shortening in vascular aging and atherosclerosis — therapeutic promise of cycloastragenol/astragaloside IV (review)View study →}.