Chamomile (Matricaria chamomilla — Apigenin)

Eases anxiety

German chamomile flowers contain the flavone apigenin (mostly as apigenin-7-glucoside), along with the essential-oil sesquiterpenes α-bisabolol and chamazulene. In 1995 researchers showed that apigenin binds the central benzodiazepine site of the GABA_A receptor and produces anxiolytic effects in mice without sedating them or impairing their muscle control.¹ It's a weak partial ligand — much gentler than a drug like diazepam, which fits the size of the human effects. (Animal — receptor pharmacology)

The human trials come from one University of Pennsylvania group (Amsterdam, Mao):

• Acute: in 57 people with mild-to-moderate generalized anxiety disorder, a chamomile extract standardized to 1.2% apigenin (220–1,100 mg/day, 8 weeks) reduced Hamilton Anxiety scores more than placebo (p = 0.047). Every secondary outcome moved the same way.²
• Long-term: 179 people with moderate-to-severe GAD took 1,500 mg/day open-label for 12 weeks, and 93 responders were then randomized to continue or switch to placebo. Relapse was lower on chamomile (15% vs 26%), but not significantly. Symptoms stayed significantly lower, and body weight and blood pressure also fell.³

Overall, a modest, real anti-anxiety effect with essentially no side effects — more reliable than chamomile's sleep reputation. (Moderate — two RCTs, one group, NIH-funded) For a stronger herb acting on the same receptor, see Chinese Skullcap, whose baicalin and wogonin are also flavone ligands at the GABA_A benzodiazepine site.

Better sleep quality

The sleep trials split by population:

• Older adults: in 60 day-care nursing-home attendees in Iran, 200 mg chamomile extract twice daily for 4 weeks improved Pittsburgh Sleep Quality Index scores compared with flour-capsule placebo (single-blind).⁴
• Postpartum women: in 80 Taiwanese women with poor sleep after giving birth, a daily cup of chamomile tea for 2 weeks improved physical-symptom-related sleep problems and depression scores. The benefit was gone 4 weeks after they stopped.⁵
• Chronic primary insomnia: in a 28-day pilot RCT in 34 adults, 270 mg extract twice daily didn't significantly change any sleep-diary measure. There was a moderate trend toward faster sleep onset and fewer awakenings, but total sleep time trended toward placebo.⁶

Chamomile helps people whose sleep is disturbed by stress, age or circumstance more than people with established insomnia. Much of the effect is probably the anxiolytic effect above plus a calming bedtime routine. (Moderate — small, mostly unblinded or open-label trials; the one proper insomnia RCT was null)

Lower blood sugar in type 2 diabetes

In an 8-week trial in 64 Iranian adults with type 2 diabetes, 3 cups a day of chamomile tea (3 g in 150 mL hot water, drunk right after meals) lowered HbA1c, serum insulin, HOMA-IR, total cholesterol, triglycerides and LDL compared with a water control.⁷ A companion paper from the same trial reported better antioxidant status. Proposed mechanisms include α-glucosidase inhibition and aldose-reductase inhibition by chamomile flavonoids. (Moderate — one small trial, water control rather than placebo tea, same group reporting both papers)

How to take it

• Tea: 2–3 g of dried flowers (about 1–2 teabags, or a heaped tablespoon of loose heads) per cup. Cover it while steeping so the volatile oils stay in the cup, and steep 5–10 minutes.
• Extract (anxiety): standardized to ~1.2% apigenin, 500–1,500 mg/day in divided doses, as in the Penn trials. A cup of tea gives only a few milligrams of apigenin, well below that.
• Type: German chamomile (Matricaria chamomilla / recutita) is the one used in the trials. Roman chamomile (Chamaemelum nobile) is a different plant.
• Quality: whole, intact flower heads keep their apigenin and oils much better than finely ground teabag dust.
• Evening pairing: with L-theanine and magnesium — different mechanisms, no known conflicts.

Safety