Benefits
Calming Effects via the Benzodiazepine Receptor
In a laboratory and mouse study, apigenin from chamomile bound the brain's benzodiazepine receptor and reduced anxiety-like behavior in mice on a maze test, and a 10-fold higher dose was mildly sedating. In a rat study it reduced movement but showed no anti-anxiety effect. No human trial of apigenin on its own for stress is cited here.
Sleep Support
Apigenin is common in evening calm and sleep formulas, partly because of chamomile's use as a bedtime tea. In a two-week trial in healthy, active adults, an evening product with 50 mg of apigenin plus magnesium L-threonate and L-theanine did not improve sleep questionnaire scores compared with placebo. No trial of apigenin alone for sleep is cited here.
Absorption From Supplements and Foods
In healthy men, pure apigenin was poorly absorbed: urinary metabolites equaled 0.5 percent of the dose over 24 hours, compared with 11.2 percent from a parsley drink and 34 percent from chamomile tea. The plant forms of apigenin, bound to sugars, were absorbed better in that study.
Antioxidant Enzyme Activity
In a crossover study of 14 adults on a controlled low-flavone diet, adding apigenin-rich parsley for one week raised the activity of two red blood cell antioxidant enzymes, glutathione reductase and superoxide dismutase. Two other enzymes and a protein oxidation marker did not change. This was a food study, not a supplement trial.
Mechanism of action
Benzodiazepine Receptor Binding
Apigenin competed with flunitrazepam at the central benzodiazepine receptor (Ki about 4 micromol/L) without affecting muscimol binding at the GABA-A receptor. In cultured brain cells it reduced GABA-activated chloride currents, and in rats its effect on movement was not blocked by a benzodiazepine antagonist, suggesting other pathways are involved. These are laboratory and animal findings.
Aromatase Inhibition
In tests on human placental and ovarian microsomes, apigenin inhibited aromatase, the enzyme that converts androgens such as testosterone into estrogens, though less potently than chrysin. No cited study measured hormone levels in people taking apigenin.
Absorption of Pure and Plant-Bound Apigenin
Pure apigenin was absorbed at low levels in healthy men, while apigenin glycosides in parsley and chamomile tea produced more metabolites in urine. In a parsley feeding study, apigenin in blood could not be measured. How much of a supplement dose reaches the brain in people has not been measured.
Clinical trials
Randomized, double-blind, placebo-controlled trial of morning adaptogens, an evening product containing 50 mg apigenin, or both, funded by the company that produced the products (Mastrofini et al. 2026, J Int Soc Sports Nutr)
103 healthy, physically active adults (average age about 35); 25 took the evening product with a morning placebo.
The evening product supplied 50 mg apigenin (from grapefruit), 2 g magnesium L-threonate and 200 mg L-theanine for two weeks. Compared with placebo it had no significant effect on perceived stress, daily stress, mood or sleep disturbance scores, and no wearable-measured sleep measure improved. The benefits seen were in the morning ashwagandha and Rhodiola rosea group. Apigenin was not tested alone.
Crossover absorption study (registered NCT03526081) comparing pure apigenin with a parsley drink, parsley in yogurt and chamomile tea (Borges et al. 2022, Free Radic Biol Med)
Healthy adult men (17 enrolled; eligible ages 25 to 60, per the trial registry).
Pure apigenin was poorly absorbed: urinary metabolites equaled 0.5 percent of intake over 24 hours. Apigenin glycosides from food did better, with 11.2 percent of intake from a parsley drink and 34 percent from chamomile tea recovered in urine. The study measured absorption only, not health effects.
Single-blind randomized controlled trial of chamomile extract capsules versus wheat flour capsules; apigenin content not reported in the abstract (Adib-Hajbaghery et al. 2017, Complement Ther Med)
60 adults aged 60 or older attending a nursing home day care center in Iran.
200 mg of chamomile extract twice a day for 28 days improved Pittsburgh Sleep Quality Index scores more than the control capsules (P<0.05). This trial tested a whole chamomile extract, not apigenin, and was single-blind, so it does not show what apigenin alone does.
Randomized crossover dietary study with added in vitro platelet tests (Janssen et al. 1998, Am J Clin Nutr)
18 healthy volunteers.
Volunteers ate 5 g of dried parsley a day, providing 84 mg of apigenin, for 7 days, compared with onions and a placebo. Parsley had no significant effect on platelet aggregation, thromboxane B2, factor VII or other clotting measures. In test tubes apigenin blocked platelet clumping only at 2500 micromol/L, a level the authors concluded cannot be reached in the body.
Randomized crossover food study on a strictly controlled low-flavone diet (Nielsen et al. 1999, Br J Nutr)
7 men and 7 women.
Adding parsley that supplied apigenin for one week raised red blood cell glutathione reductase and superoxide dismutase activity compared with the basic diet, while catalase, glutathione peroxidase and a plasma protein oxidation marker did not change. About 0.58 percent of the apigenin eaten appeared in urine.