Apigenin is a yellow plant pigment from the flavone group of flavonoids. Dried chamomile flowers and parsley are its richest food sources, and smaller amounts occur in celery, artichoke and some grains (Hostetler et al., Adv Nutr 2017). Isolated apigenin is sold as a supplement, mostly promoted for sleep and, more recently, for raising NAD+ levels.
The most important fact is that almost all of the evidence comes from lab dishes, animals or chamomile extract. Chamomile extract has been tested in small human trials for anxiety and sleep, but it contains many compounds besides apigenin. We found no published placebo-controlled trial of isolated apigenin alone for sleep or anxiety. The claims that it blocks aromatase or the NAD+-degrading enzyme CD38 rest on cell and rodent studies.
This page summarizes what human absorption studies, chamomile trials and laboratory research report. It is for education only and is not medical advice.
| Property | Detail |
|---|---|
| Class | Flavone (a subgroup of flavonoids); chemically 4’,5,7-trihydroxyflavone |
| Formula and weight | C₁₅H₁₀O₅, 270.24 g/mol (PubChem) |
| Richest dietary sources | Dried chamomile flowers, dried and fresh parsley; smaller amounts in celery and artichoke |
| Form in food | Mostly bound to sugars (glycosides), such as apiin in parsley and apigenin-7-glucoside in chamomile |
| Doses studied in humans | No dose-finding trials of isolated apigenin; 50 mg/day inside a multi-ingredient sleep product; chamomile extract trials used 220–1,500 mg/day of extract |
| Half-life | No human elimination half-life published; plasma apigenin peaked at 7.2 h after a parsley meal; in rats, blood radioactivity had a 91.8 h half-life |
| Key lab findings | Binds the benzodiazepine site in receptor-binding assays; inhibits CD38 and aromatase in cell-free and cell assays |
| US status | Not an approved drug; supplements are not FDA-approved before sale |
| WADA status | Not named on the 2026 Prohibited List |
What it is
Apigenin’s chemical name is 5,7-dihydroxy-2-(4-hydroxyphenyl)chromen-4-one (PubChem). It is a close relative of other flavones such as luteolin and chrysin. In plants, flavones help absorb ultraviolet light and defend against insects and fungi (Hostetler et al. 2017).
In food, apigenin is almost always attached to a sugar. Chamomile contains acetyl, malonyl and caffeoyl forms of apigenin-7-O-glucoside. Parsley contains mainly apiin (apigenin-7-O-apiosylglucoside) and its malonyl form. Supplements, by contrast, usually contain the free compound (the “aglycone”).
Dietary sources
A 2017 review collected published concentrations. Values vary widely between studies because growing conditions, plant part and processing change flavone content (Hostetler et al. 2017):
| Food | Apigenin content (per 100 g) | Per serving (as defined in the review) |
|---|---|---|
| German chamomile flowers, dried | 5,010–5,320 mg (as glycosides) | 100–106 mg per 2 g |
| Roman chamomile flowers, dried | 2,531 mg glycosides plus 395 mg free apigenin | 51 mg glycosides plus 8 mg free per 2 g |
| Parsley, dried | 1,200–1,350 mg | 24–27 mg per 2 g |
| Parsley, fresh | Up to 1,484 mg (highest of the fresh foods reviewed) | Not applicable |
| Chinese celery | 24.0 mg | 48 mg per 200 g |
| Celery hearts | 19.1 mg | 38 mg per 200 g |
| Celery stalks | 1.3–10.8 mg | 3–22 mg per 200 g |
| Artichoke heads | 3.9–18.9 mg (apigenin and glycosides) | 8–38 mg per 200 g |
Reported intakes of all flavones combined (apigenin, luteolin and related compounds) are low: 0.7–9.0 mg/day in European adults and 1.1–1.6 mg/day in US women.
Pharmacokinetics
Human data are limited to a handful of small studies. Most absorbed apigenin circulates as glucuronide or sulfate conjugates made in the gut wall and liver, not as the free compound (Hostetler et al. 2017).
Parsley. Eleven healthy adults ate 2 g blanched parsley per kg of body weight (about 65.8 µmol apigenin) after an apigenin-free diet (Meyer et al., Ann Nutr Metab 2006):
| Measure | Result |
|---|---|
| Peak plasma apigenin | 127 ± 81 nmol/L, with large differences between people |
| Time to peak | 7.2 ± 1.3 h |
| Plasma level at 28 h | Below the detection limit (2.3 nmol/L) in all participants |
| Urinary apigenin over 24 h | 0.22% ± 0.16% of the dose |
Pure apigenin vs glycosides. In a 2022 study in healthy men, free apigenin taken by mouth was poorly absorbed: urinary metabolites equaled only 0.5% of intake over 24 hours. The glycosides in food did better (Borges et al., Free Radic Biol Med 2022):
| Source | Time to peak of main metabolite (apigenin-4’-glucuronide) | Urinary metabolites, % of intake |
|---|---|---|
| Free apigenin | Not reported in abstract | 0.5% |
| Parsley drink | 4 h | 11.2% |
| Dried parsley with yogurt | 6 h | Not reported in abstract |
| Chamomile tea | 2 h | 34% |
This matters for supplements: the form most often sold (free apigenin) was the least well absorbed form in this study.
Half-life. No elimination half-life for apigenin in humans has been published; the human data tables in the 2017 review leave this field empty (Hostetler et al. 2017). In rats given radiolabeled apigenin by mouth, radioactivity appeared in blood only after 24 h and had an elimination half-life of 91.8 h, which the authors read as slow absorption and slow elimination (Gradolatto et al., Drug Metab Dispos 2005). That figure tracks total radioactivity in rats and should not be applied to people.
Across human studies, plasma flavone levels after food stay below 1 µmol/L (Hostetler et al. 2017). Most of the lab effects described below were measured at about 1–100 µmol/L.
Regulatory status
- United States: apigenin is not an approved drug for any condition. Herbal and botanical products for oral use are usually marketed as dietary supplements, which FDA does not approve before sale (NCCIH).
- Sport: apigenin is not named on the WADA 2026 Prohibited List. Class S4.1 (aromatase inhibitors) is open-ended (“including, but not limited to”) and names one synthetic flavone, α-naphthoflavone. We found no WADA statement that dietary flavones such as apigenin fall under S4.1.
What the research shows
Sleep
Isolated apigenin. We found no published randomized trial of apigenin alone for sleep. The closest is a 2026 double-blind trial in 103 healthy, physically active adults. One evening product contained 50 mg apigenin plus magnesium L-threonate (145 mg magnesium) and 200 mg L-theanine, taken for 2 weeks (Mastrofini et al., J Int Soc Sports Nutr 2026):
| Outcome | Evening apigenin product vs placebo |
|---|---|
| Perceived stress (PSS) | No difference (p = 0.684) |
| Patient-reported sleep disturbance (PROMIS) | No difference (p = 0.478) |
| Global Pittsburgh Sleep Quality Index | No group or interaction effect for any group |
| Wearable-measured sleep quality, efficiency, latency, total sleep time | No effects |
| Wearable-measured wake after sleep onset | Increased after week 2 (p = 0.009) |
The clearest benefits were in the morning group taking ashwagandha and Rhodiola, which had no apigenin. The trial was funded by the product’s maker. Because apigenin was combined with other ingredients, it cannot isolate apigenin’s effect either way.
Chamomile extract (not isolated apigenin). Chamomile trials are often cited for apigenin, but the extracts contain many other compounds.
- In a pilot randomized, double-blind trial, 34 adults with chronic primary insomnia took 270 mg chamomile extract twice daily or placebo for 28 days. There were no significant differences in total sleep time, sleep efficiency, time to fall asleep, waking after sleep onset, sleep quality or awakenings (Zick et al., BMC Complement Altern Med 2011). Lab testing found 3.9 mg apigenin per 90 mg tablet, taken as six tablets a day.
- A 2024 meta-analysis of 10 studies (772 participants) found the Pittsburgh Sleep Quality Index improved by 1.88 points (95% CI −3.46 to −0.31), with very high heterogeneity (I² 88.4%). Sleep duration, sleep efficiency and daytime functioning did not improve. Only one included study tested the product’s purity or potency (Kazemi et al., Complement Ther Med 2024).
Diet surveys. In a cross-sectional study of 1,936 adults in southern Italy, people in the highest quarter of estimated dietary apigenin intake were less likely to report inadequate sleep quality than those in the lowest (OR 0.63, 95% CI 0.44–0.90) (Godos et al., Nutrients 2020). This design cannot show that apigenin caused better sleep; apigenin intake also tracks with overall diet.
The chamomile page covers the chamomile sleep trials in more detail.
Anxiety
All controlled human anxiety data come from chamomile extract, not isolated apigenin. Both trials below used a German chamomile extract, and the first one was standardized to 1.2% apigenin.
| Trial | Design | Dose | Main result |
|---|---|---|---|
| Amsterdam et al. 2009 | Randomized, double-blind, placebo-controlled; 57 adults with mild to moderate generalized anxiety disorder (GAD); 8 weeks | 220 mg capsules, 1 to 5 a day | Greater drop in Hamilton Anxiety (HAM-A) score than placebo (p = 0.047); authors called the effect “modest” |
| Mao et al. 2016 | 179 adults with moderate to severe GAD on 12 weeks open-label extract; 93 responders randomized to extract or placebo for 26 weeks | 1,500 mg/day (500 mg three times daily) | Relapse 15.2% vs 25.5%; hazard ratio 0.52 (95% CI 0.20–1.33; p = 0.16, not significant); GAD symptoms stayed lower on chamomile (p = 0.0032) |
Mechanism (lab and animal data). In receptor-binding assays, apigenin isolated from chamomile displaced flunitrazepam from the benzodiazepine site of the GABA-A receptor with a Ki of 4 µM. In mice, it reduced anxiety-like behavior without sedation, and a 10-fold higher dose was mildly sedating (Viola et al., Planta Med 1995). A later study did not reproduce the calming effect: in rats injected with apigenin, locomotor activity fell but there was no anti-anxiety effect, and in cultured nerve cells apigenin reduced rather than enhanced GABA-activated currents (Avallone et al., Biochem Pharmacol 2000). The 4 µM binding constant is also well above the plasma levels measured in people after food (127 nmol/L after a large parsley meal).
CD38 and NAD+ (lab and mouse data only)
NAD+ (nicotinamide adenine dinucleotide) is a coenzyme involved in energy metabolism; the enzyme CD38 is a major consumer of it. The CD38 claim comes from one Mayo Clinic study (Escande et al., Diabetes 2013):
| Model | Finding |
|---|---|
| Purified human CD38 (cell-free) | Apigenin inhibited NAD+-degrading activity with an IC₅₀ of 10.3 µmol/L |
| Cultured cells | 25 µmol/L apigenin raised intracellular NAD+ and lowered protein acetylation, consistent with sirtuin activation |
| Obese mice (6 per group) | 100 mg/kg apigenin injected into the abdomen daily for 7 days raised liver NAD+ and improved glucose tolerance |
Three gaps separate this from human use:
- The mice received apigenin by injection, which bypasses the poor oral absorption seen in people.
- The IC₅₀ of about 10 µmol/L is far above the human plasma peak of 0.127 µmol/L reported after a large parsley meal (Meyer et al. 2006).
- We found no human study measuring NAD+ levels after apigenin.
For compounds with human NAD+ data, see the pages on NAD+, NMN and nicotinamide riboside.
Aromatase and testosterone (lab and animal data only)
Aromatase is the enzyme that converts testosterone to estradiol. Apigenin inhibits it in lab assays:
| Study | Model | Apigenin result |
|---|---|---|
| Jeong et al. 1999 | Aromatase from human placenta (cell-free) | IC₅₀ 0.9 µg/mL, among the most active of 28 flavonoids |
| Sanderson et al. 2004 | Human adrenal cancer cells (H295R) | IC₅₀ 20 µM, with some cytotoxicity at 100 µM; the drug control 4-hydroxyandrostenedione had an IC₅₀ of 20 nM |
| Saarinen et al. 2001 | Immature rats, 50 mg/kg by mouth | No effect on estrogen- or androgen-driven uterine growth; authors cite poor absorption |
The rat study is the only live-animal test of the aromatase claim we found, and it was negative at a dose the authors describe as considerably above daily dietary amounts. No human study has measured estradiol or testosterone after apigenin.
Effects on testosterone production in lab models point in both directions. At 100 µM, apigenin inhibited androgen production in rat Leydig cells (the testosterone-producing cells of the testis) and blocked two human testosterone-making enzymes (3β-HSD and 17β-HSD3), with IC₅₀ values of 2.17 and 1.31 µM (Wang et al., Fitoterapia 2016). In contrast, in obese mice on a high-fat diet, 10 mg/kg apigenin improved testicular markers and restored testosterone-related proteins (Wu et al., Biomed Pharmacother 2024). Neither result has been tested in people.
Side effects and risks
Tolerability
There is no systematic human safety data set for isolated apigenin. In the 2026 combination trial, the two withdrawals for side effects (diarrhea; dizziness with muscle weakness) were both in the morning group without apigenin, and no other study-related adverse events were reported (Mastrofini et al. 2026). In chamomile extract trials, adverse events were similar to placebo (Amsterdam et al. 2009; Zick et al. 2011; Mao et al. 2016). These trials were small and short.
Drug interactions
- CYP2C9 (lab data): apigenin inhibited the liver enzyme CYP2C9, which clears drugs such as losartan and warfarin. In human liver microsomes, it blocked losartan metabolism with an IC₅₀ of 4.10 µmol/L (Wang et al., Pharmacology 2016). Whether supplement doses reach this level in the liver is unknown.
- Chamomile and warfarin: interactions between chamomile and warfarin, and with some liver-metabolized drugs, have been reported. NCCIH also lists a theoretical interaction with sedatives (NCCIH).
Allergy (chamomile products)
Chamomile can cause allergic reactions, including anaphylaxis. People allergic to ragweed, chrysanthemums, marigolds or daisies are more likely to react (NCCIH). This applies to chamomile tea and extracts; it has not been shown for purified apigenin.
Hormonal effects
Rodent researchers describe apigenin as a weakly estrogenic compound (Gradolatto et al. 2005), although oral doses of 50 mg/kg did not stimulate uterine growth in immature rats (Saarinen et al. 2001). NCCIH notes that chamomile might have estrogen-like effects, might reduce the effect of birth control pills and might worsen estrogen-sensitive conditions such as breast or uterine cancer (NCCIH).
Pregnancy and breastfeeding
Little is known about chamomile safety in pregnancy or breastfeeding (NCCIH), and we found no human safety data for apigenin supplements in these groups.
Key takeaways
- A food flavone, mostly from chamomile and parsley. Dried chamomile flowers and parsley contain far more apigenin than other foods, mostly in sugar-bound form.
- Poorly absorbed as a pure supplement. Free apigenin produced urinary metabolites equal to only 0.5% of intake, vs 34% from chamomile tea; plasma levels after food stay below 1 µmol/L.
- The sleep and anxiety data are for chamomile extract. Small trials show a modest anxiety benefit and mixed sleep results; the one trial with 50 mg apigenin (in a combination product) found no sleep or stress benefit.
- CD38 and NAD+ claims are lab and mouse findings. The key mouse study injected 100 mg/kg into the abdomen; no human study has measured NAD+ after apigenin.
- No evidence it lowers estrogen in living animals or people. Apigenin inhibits aromatase in lab assays, but oral dosing in rats showed no anti-estrogen effect, and lab effects on testosterone production point both ways.
- Interaction and allergy cautions are documented. Apigenin inhibits CYP2C9 in vitro, and chamomile products have reported interactions with warfarin and can cause allergic reactions.
Sources
- National Center for Biotechnology Information. PubChem Compound Summary for CID 5280443, Apigenin. PubChem.
- Hostetler GL, Ralston RA, Schwartz SJ. Flavones: food sources, bioavailability, metabolism, and bioactivity. Adv Nutr. 2017;8(3):423–435. PubMed; PMC.
- Meyer H, Bolarinwa A, Wolfram G, Linseisen J. Bioavailability of apigenin from apiin-rich parsley in humans. Ann Nutr Metab. 2006;50(3):167–172. PubMed.
- Borges G, Fong RY, Ensunsa JL, et al. Absorption, distribution, metabolism and excretion of apigenin and its glycosides in healthy male adults. Free Radic Biol Med. 2022;185:90–96. PubMed.
- Gradolatto A, Basly JP, Berges R, et al. Pharmacokinetics and metabolism of apigenin in female and male rats after a single oral administration. Drug Metab Dispos. 2005;33(1):49–54. PubMed.
- National Center for Complementary and Integrative Health. Chamomile: usefulness and safety. NCCIH.
- World Anti-Doping Agency. World Anti-Doping Code International Standard: Prohibited List 2026. WADA 2026 Prohibited List.
- Mastrofini GF, Romersi RF, Lombardi MG, et al. Modulating stress and sleep through a multi-compound dietary supplement: a randomized, double-blind, placebo-controlled trial. J Int Soc Sports Nutr. 2026;23(1):2740227. PubMed; PMC.
- Zick SM, Wright BD, Sen A, Arnedt JT. Preliminary examination of the efficacy and safety of a standardized chamomile extract for chronic primary insomnia: a randomized placebo-controlled pilot study. BMC Complement Altern Med. 2011;11:78. PubMed; PMC.
- Kazemi A, Shojaei-Zarghani S, Eskandarzadeh P, Hashempur MH. Effects of chamomile (Matricaria chamomilla L.) on sleep: a systematic review and meta-analysis of clinical trials. Complement Ther Med. 2024;84:103071. PubMed.
- Godos J, Ferri R, Castellano S, et al. Specific dietary (poly)phenols are associated with sleep quality in a cohort of Italian adults. Nutrients. 2020;12(5):1226. PubMed; PMC.
- Amsterdam JD, Li Y, Soeller I, et al. A randomized, double-blind, placebo-controlled trial of oral Matricaria recutita (chamomile) extract therapy for generalized anxiety disorder. J Clin Psychopharmacol. 2009;29(4):378–382. PubMed; PMC.
- Mao JJ, Xie SX, Keefe JR, et al. Long-term chamomile (Matricaria chamomilla L.) treatment for generalized anxiety disorder: a randomized clinical trial. Phytomedicine. 2016;23(14):1735–1742. PubMed.
- Viola H, Wasowski C, Levi de Stein M, et al. Apigenin, a component of Matricaria recutita flowers, is a central benzodiazepine receptors-ligand with anxiolytic effects. Planta Med. 1995;61(3):213–216. PubMed.
- Avallone R, Zanoli P, Puia G, et al. Pharmacological profile of apigenin, a flavonoid isolated from Matricaria chamomilla. Biochem Pharmacol. 2000;59(11):1387–1394. PubMed.
- Escande C, Nin V, Price NL, et al. Flavonoid apigenin is an inhibitor of the NAD+ase CD38: implications for cellular NAD+ metabolism, protein acetylation, and treatment of metabolic syndrome. Diabetes. 2013;62(4):1084–1093. PubMed; PMC.
- Jeong HJ, Shin YG, Kim IH, Pezzuto JM. Inhibition of aromatase activity by flavonoids. Arch Pharm Res. 1999;22(3):309–312. PubMed.
- Sanderson JT, Hordijk J, Denison MS, et al. Induction and inhibition of aromatase (CYP19) activity by natural and synthetic flavonoid compounds in H295R human adrenocortical carcinoma cells. Toxicol Sci. 2004;82(1):70–79. PubMed.
- Saarinen N, Joshi SC, Ahotupa M, et al. No evidence for the in vivo activity of aromatase-inhibiting flavonoids. J Steroid Biochem Mol Biol. 2001;78(3):231–239. PubMed.
- Wang X, Wang G, Li X, et al. Suppression of rat and human androgen biosynthetic enzymes by apigenin: possible use for the treatment of prostate cancer. Fitoterapia. 2016;111:66–72. PubMed.
- Wu L, Qu J, Mou L, Liu C. Apigenin improves testosterone synthesis by regulating endoplasmic reticulum stress. Biomed Pharmacother. 2024;177:117075. PubMed.
- Wang Z, Gong Y, Zeng DL, et al. Inhibitory effect of apigenin on losartan metabolism and CYP2C9 activity in vitro. Pharmacology. 2016;98(3-4):183–189. PubMed.