Aubergine powder, blood pressure and mood in stressed people
What it found
In 100 stressed adults with normal-high blood pressure or grade 1 hypertension, taking aubergine powder capsules for 12 weeks lowered some blood pressure readings compared with placebo, and improved some mood scores.
This was the first such trial in people.
What they found
Studies in people
Hospital blood pressure
Aubergine powder significantly decreased hospital diastolic blood pressure at week 8 overall and in the normal-high blood pressure group, and systolic and diastolic blood pressure at week 12 overall and in the grade 1 hypertension group, compared with placebo.
Home blood pressure
Morning systolic and diastolic blood pressure at week 4 were significantly decreased in the aubergine group compared with placebo. In normal-high blood pressure participants, morning systolic and diastolic blood pressure at week 4 and evening diastolic blood pressure at weeks 4 and 8 were also improved.
Stress and mood
There were no differences in stress scores between groups. Aubergine intake improved some negative mood scores at week 8 or 12 in the normal-high blood pressure group, and some positive mood scores in the grade 1 hypertension group.
Safety measures
Body composition, blood counts, liver and kidney function, lipid profiles and blood glucose profiles all stayed within reference ranges. The principal investigator judged that all adverse effects were not related to the test food.
Other findings
Active compound
The authors estimate that the blood pressure effect came from eggplant-derived choline ester, namely acetylcholine, because the amounts of GABA and chlorogenic acid in the test food were below their effective doses.
What the authors conclude
“A randomized, double-blind, placebo-controlled, parallel-group comparative study showed that ingestion of eggplant powder for 12 weeks improved BP and PSs without side effect.”
Also in their conclusions
- They conclude that aubergine powder intake significantly improved blood pressure and psychological state compared with the control group.
- They say this was the first evidence of the antihypertensive and psychological-state-improving effects of aubergine.
- They advise that aubergine is expected to be utilized as a safe treatment for blood pressure and mental health.
How it was done
The authors note that eggplant is a globally popular vegetable whose significant health effects had not been reported in randomized controlled trials. They had previously found that eggplant is rich in choline esters, including acetylcholine, and had an antihypertensive effect in spontaneously hypertensive rats.
They enrolled 100 Japanese participants with normal-high blood pressure or grade 1 hypertension and randomly assigned them to aubergine powder capsules (1.2 g/day, providing 2.3 mg of acetylcholine per day) or placebo capsules for 12 weeks. Hospital blood pressure was the primary outcome; home blood pressure, stress and psychological state were secondary outcomes. After dropouts, 36 people in the aubergine group and 41 in the placebo group were included in the efficacy analysis.
What it can’t tell you
- This trial lasted 12 weeks, so it cannot show what happens over longer periods.
- The results apply to stressed adults with normal-high blood pressure or grade 1 hypertension, not to everyone.
- The authors note that the blood pressure effects were mild and gradual, and that environmental factors such as temperature may have affected the results.
Who paid
- Funding
- Funded by National Agriculture and Food Research Organization (from the PubMed record).
- Conflicts
- The authors declared no conflicts of interest.
- Authors work at
- Hokkaido Information University, Japan; Shinshu University, Japan
The paper
- Title
- Daily Ingestion of Eggplant Powder Improves Blood Pressure and Psychological State in Stressed Individuals: A Randomized Placebo-Controlled Study
- Type
- Randomised controlled trial
- Evidence
- Studies in people
- Summarised from
- Full text
- Licence
- CC BY. Words in quotation marks are the authors’; the rest is our summary.
- Cite
- Nishimura M, Suzuki M, Takahashi R, et al (2019). Daily Ingestion of Eggplant Powder Improves Blood Pressure and Psychological State in Stressed Individuals: A Randomized Placebo-Controlled Study. Nutrients. doi:10.3390/nu11112797Free full textPubMed 31744060DOI
Summary written 30 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error