The Bedtime Tea, Now in Capsule Form
Chamomile tea is the classic wind-down drink. Apigenin, one of chamomile's best-known compounds, has become a staple of "sleep stacks" in biohacking circles. A 2017 randomized trial in Complementary Therapies in Medicine tested a more concentrated version of the idea. It gave older adults 400 mg of chamomile extract a day for four weeks and tracked their sleep quality afterward.
The paper's conclusion is that chamomile extract "can significantly improve sleep quality among elderly people." The details are more modest, and more useful, than that headline suggests.
Study Design: Simple and Practical
Researchers at Kashan University of Medical Sciences in Iran ran a single-blind randomized controlled trial at the Kahrizak day-care nursing home in Karaj, Iran.
- Participants: 60 adults aged 60 or older. Average age was about 70 in the control group and about 69 in the treatment group.
- Intervention: Chamomile extract capsules, 200 mg twice daily (400 mg/day), for 28 consecutive days.
- Control: Wheat-flour capsules of the same size, taken the same way.
- Measurement: The Pittsburgh Sleep Quality Index (PSQI), a standard questionnaire, at four time points: before starting, two weeks in, right after the 28 days, and two weeks after stopping.
That last time point matters. Many supplement studies stop measuring when the supplement stops, so they can't say whether any benefit outlasts use.
The Results: What Changed and What Didn't
At baseline, both groups had poor sleep quality, with no significant difference between them (P=0.639). The groups differed on one component, habitual sleep efficiency. After the intervention, sleep quality in the chamomile group was significantly better than in the control group (P<0.05).
Summaries of the paper's data add specifics:
- PSQI scores dropped by roughly 3 points in the chamomile group, a change generally considered clinically meaningful. Lower PSQI scores mean better sleep.
- Participants fell asleep faster (shorter sleep latency).
- They woke less often during the night.
- Total sleep duration did not change.
- The benefit persisted two weeks after stopping the capsules.
The duration finding is the most useful reality check. Chamomile didn't make these older adults sleep longer. It appears to have improved how they slept: how quickly they dropped off and how continuous the night was. Participants also still had moderate sleep problems at the end, so this was an improvement, not a cure.
The Apigenin Angle: Plausible, Not Proven Here
The proposed mechanism is that apigenin, a flavonoid in chamomile, binds benzodiazepine sites on GABA-A receptors. These receptors are part of the brain's main inhibitory signaling system, which is also targeted by prescription sedatives, though the proposed effect from chamomile is much milder.
This trial did not measure apigenin levels or brain activity, and it didn't test apigenin on its own. It tested a chamomile extract, which contains many compounds. The mechanism is a reasonable hypothesis from the broader literature, not something this study demonstrated. Treat "apigenin did it" as a plausible explanation, not a finding.
Limitations to Keep in Mind
The paper's own design limits how far you can push the conclusions:
- Single-blind only. Participants didn't know which capsule they got, but the people running the study may have. That leaves room for bias.
- Small sample. Sixty people is enough for a signal, not for firm conclusions.
- One site, one population. Older adults at a single day-care nursing home in Iran may not represent younger adults, other cultures, or people living independently.
- Self-reported outcomes. The PSQI is a validated questionnaire, but it is still subjective. No sleep-tracking device or lab measure was used.
- Poorly described extract. The standardization of the extract, meaning how much apigenin or other active compounds each capsule contained, isn't well described. That makes it hard to replicate with an off-the-shelf product.
- Short follow-up. The two-week post-treatment check is encouraging, but it says nothing about months of use.
Practical Takeaways
The dose used: 200 mg of chamomile extract, twice a day, for 28 days. If you're comparing products, this is the only regimen with evidence behind it here. Taking more, or taking it as a single nightly dose, goes beyond what was studied.
How it compares to tea: The trial didn't test tea, so there's no head-to-head data. A cup of tea and a standardized extract capsule differ in concentration and consistency, and the paper can't say whether tea would work equally well. Tea may still help as a calming ritual, but you can't assume it delivers the same effect.
Who it's for: The evidence applies most directly to adults 60 and older with poor sleep quality. For younger people, this study is suggestive at best. It's also not a treatment for diagnosed insomnia, sleep apnea, or other medical sleep disorders, and persistent sleep problems deserve a clinician's attention.
Safety flags:
- Ragweed and related allergies. Chamomile belongs to the daisy (Asteraceae) family, and people allergic to ragweed, chrysanthemums, or similar plants can react to it. If that's you, be cautious or avoid it.
- Sedatives and sleep medications. Because chamomile is thought to act on GABA-related pathways, combining it with benzodiazepines, sleep drugs, alcohol, or other sedating supplements could add to drowsiness. Check with a doctor or pharmacist first, especially if you take multiple medications, as many older adults do.
- Stacking. Adding chamomile to a multi-ingredient sleep stack makes it impossible to tell what's helping, and the trial tested chamomile alone.
The Bottom Line
This small but well-structured trial suggests that 400 mg a day of chamomile extract for four weeks may improve self-reported sleep quality in older adults, with faster sleep onset, fewer awakenings, and benefits that lingered for two weeks after stopping. It did not lengthen sleep, and the people in it still had moderate sleep problems. The apigenin story is plausible but unproven here, and the single-blind design, small sample, and single site call for larger, better-controlled replication. For now, it's a promising, low-risk option for some older adults, not a magic sleep pill.
