Peppermint oil reduces blood pressure by 8.48 mmHg in small study (journals.plos.org)
69 points by brandonb 7 hours ago
jrflo 14 minutes ago
Whenever I see a study like this I assume that the researchers won the p<0.05 lottery
Lu2025 4 minutes ago
Well, mint tea does make me sleepy
jeffnv 4 hours ago
Noticing that the waist circumference on average went down on the peppermint group (85.17 -> 84.61) while the placebo group it went up (88.33 -> 88.65)? Also the resting heart rate dropped for the peppermint group. My initial suspicion is that the peppermint group coincidentally was also the 'got in better shape' group. Maybe the peppermint helped, but for relatively small groups that also seem to be improving waist circumference and heart rates likely due to good diet and exercise, I'm not convinced the peppermint did jack shit. More investigation needed! Would be awesome if it helped though!
vector_spaces an hour ago
There has been some research on spearmint suggesting anti-androgen effects in PCOS, which is a bit unexpected to me as I wouldn't expect mint-family herbs to have much hormone modulating effect at all. I would imagine there to be similarities in profile between spearmint and peppermint so perhaps a related mechanism is involved, although I would probably expect the opposite outcome as a naive layperson. But I haven't closely evaluated the paper nor do I know whether there's been much else suggesting this
It is important to remember that herbs are difficult to study in this setting compared with isolated compounds -- likely because their pharmacological and chemical compositions are sensitive to many factors: hour and season of harvest, form consumed (raw powder, alcohol extract, cold water infusion, fat emulsion, hot water infusion, combustion, pyrolysis, essential oil), part consumed (leaf, root, flower, seed), among staggeringly many others. Anyone with experience consuming cannabis or coffee can probably testify to the above
Not to mention that the pharmacologically active compounds in many plants are far from being comprehensively understood, let alone their interactions and dynamics
This isn't to say that every claim about herbs is to be taken seriously. My point here is more that there is no good reason to dismiss the herb itself as a cause yet simply because it's an herb and a fairly mundane one at that. There are easy examples of herbs which have pronounced physiological effects, used for recreation, performance enhancement, as literal poison, to induce labor, to thin the blood -- among others.
r0ze-at-hn 35 minutes ago
So spearmint is not peppermint. Peppermint (mentha pipereta in this study) inhibits CYP3A4 and CYP1A2. CYP1A2 is in the liver and if that is inhibited then estrogen will route down the CYP1B1 path so the ratio of the two metabolites 2-OHE1 v.s 4-OHE1 would be altered. For the PCOS (renamed to PMOS btw) if they start with elevated 2-OHE1 after the peppermint this could result in improve estrogen signaling because the now raised 4-OHE1 has much higher affinity than the 2-OHE1 for ESR1 (Era). ESR1 in particular is known for lowering blood pressure.
This particular path isn't that crazy, but it would only be for a subset of folk. From the study there is something simpler: menthol acts as a natural calcium-channel blocker, triggering vasodilation to reduce blood pressure.
mrob an hour ago
>I wouldn't expect mint-family herbs to have much hormone modulating effect at all
Mints are closely related to pennyroyal (Mentha pulegium), which was traditionally (and dangerously because of toxicity) used as an abortifacient. Its mechanism of action is still unknown, so hormone modulating effects seem plausible to me.
samudrijan an hour ago
rshm an hour ago
ktm5j 2 hours ago
But weight/mass didn't change one bit (okay exaggeration, but not by much), so maybe peppermint helps relieve gas. Who knows? There's a lot that this data could mean, and no simple way to figure it out.
ajb 43 minutes ago
It's actually prescribed for that: https://www.nhs.uk/medicines/peppermint-oil/
bherms an hour ago
i actually had heard it helps w/ bloating/stomach issues online and took for a while and def noticed a debloating effect and less gas... obviously 1 anecdote, but I'd assume any slight waistline reduction is due to that. Also sidenote: pooping often made it feel like I put a breathmint... up... "there" lol
simondotau 3 minutes ago
samudrijan an hour ago
mlmonkey 2 hours ago
Peppermint oil has traditionally been used in India for digestion, so you may be on to something. I remember this particular brand growing up: https://www.amazon.com/clp/B001NQ7S9G (no relation).
f33d5173 an hour ago
Nothing but blood pressure and heart rate was significant, and heart rate only barely so. I wouldn't read anything into the other numbers. It was a 20 day study, you aren't going to get long term outcomes from that.
potatoking 3 hours ago
I'd think weight could be causal for hypertension result or sentiment over health measurement could have been causal for weight or the study could just be too small.
criddell 2 hours ago
When you say weight, do you really mean obesity? And if you are talking about weight, is it likely that people who live in low gravity environments will have fewer hypertension problems?
crooked-v an hour ago
Wild-ass guess: maybe the aftertaste of peppermint oil twice daily leaves people who are already unhealthy wanting to snack less, leading to minor weight loss.
simondotau a few seconds ago
As a bit of random speculation: improved digestion might reduce the “needy stomach” sensation associated with hunger.
rolisz 4 hours ago
Maybe it helps with weight loss (I wish)
yumraj 3 hours ago
It seems to aid in digestion, soothe upset stomach, so maybe it does.
reilly3000 14 minutes ago
Aren’t people generally getting some via toothpaste?
yumraj 4 hours ago
There are two types of peppermint supplements being sold: mentha pipereta that this study looked at, and mentha arvensis.
I wonder if mentha arvensis has the same effect. Supplements vs mint tea would be another interesting thing to study in future.
kzrdude 2 hours ago
Based on your new information, I think it would be good to test the effect of supplemenths vs supplemints.
Palomides 2 hours ago
HN really upvotes some dumb medical articles, come on, n=20 about peppermint?
binarymax 2 hours ago
I've got an n=65 about hibiscus and blood pressure, which has been better well known for awhile. https://www.ars.usda.gov/news-events/news/research-news/2008...
spathi_fwiffo an hour ago
now we need a study of adding Peppermint oil into hybiscus tea.
SwellJoe an hour ago
rozap 2 hours ago
Silence, we have disruptive direct to consumer peptide startups that need to pump.
ChickeNES 2 hours ago
From PLOS One as well! I remember in college, I was taking a bio class that taught how to read journal articles...and a psych class that was assigning them. Psych class assigned almost solely PLOS One articles...which didn't survive the criticism I was being taught in the bio class lmao
pessimizer an hour ago
If there's anything consistent about HN as long as I've been on it, it's that HN is orthorexic.
doublepg23 an hour ago
> orthorexic
New word of the day!
catigula an hour ago
The funny thing is, I've read countless meta-analyses on various mainstream drugs, where total n=hundreds of thousands, and I still don't know if they work at all or not.
overtone1000 4 hours ago
That is very accurate sphygmomanometry!
I_dream_of_Geni 4 hours ago
I'm guessing that this number is the result of the average of "x" people in the study, and not an individual measurement. But, yeah, I see what that looks like.
techteach00 an hour ago
Also works well for IBS. Popular brand name green box. Bit pricey.
alastairr 3 hours ago
Peppermint group N=20. Mkay. 2 of those lost to followup, one because they didn't like the taste (control group got peppermint cordial). The result might be real but needs followup before we all starting gulping down peppermint oil.
bryceacc 2 hours ago
>50 µL of supplement diluted into 100 mL of water
pretty tiny amount of peppermint was consumed
HeyLaughingBoy 2 hours ago
I was surprised by this too. From a background in writing code to control precision pumps, I have a good idea of what 50 µL looks like and it seemed like an awfully small amount. But I don't know how concentrated the oil is.
FWIW, I had an Indian co-worker who took peppermint oil frequently and said that it was very good for his upset stomach.
jeffbee 2 hours ago
That's enough to turn a whole barrel of water detectably minty.
DonHopkins 3 hours ago
Doctor Bronner was right!
Peppermint - Pure-Castile Magic Soap: Cool, Refresh, and Awaken with Invigorating Peppermint
https://www.drbronner.com/products/peppermint-pure-castile-l...
Dr. Bronner invented the peppermint oil soap for soiled diapers
https://www.sandiegoreader.com/news/1978/nov/02/cover-look-f...
Created in California: How Dr. Bronner’s became the soap for every subculture
https://www.latimes.com/business/story/2023-07-12/dr-bronner...
>Perhaps inspired by that experimental ethos, customers have discovered their own unusual uses in the years since Emanuel started mixing gallons of peppermint castile soap out of his Pershing Square tenement apartment in 1948. [...]
>David, Mike and Lisa Bronner grew up in Glendale, not giving much thought to the prospect of one day taking over the family business and generally regarding their grandfather as a bewildering figure.
>“My granddad was always talking about uniting ‘Spaceship Earth,’ and it was kind of sailing over our heads,” David said.
>“He’d be talking to us as if we were all PhD students in religious studies,” Mike said of visits to Emanuel’s home when the siblings were in elementary school. “He was blind, and every once in a while he would say, ‘Are you there?’ and we’d be like, “All-one, Grandpa!’ And he’d be like, ‘Very good. OK, I want you to recite the peppermint bottle.’”
Lisa Bronner: The Poetry of the Lavender Label
https://www.lisabronner.com/the-poetry-of-the-lavender-label
>The label on the quart size of the Lavender Pure-Castile Magic Soap holds the greatest insight for me into his motivations and goals. The Peppermint label records the tenets of his Moral ABC, his guidelines for humanity to find unity and a path forward. But it is the Lavender quart that hosts his poetry, and in that I see his heart. [...]
>"To keep my health! To do my work! To love, to live!"
>"Great peace is found in little busyness."
>"Work well yourself and work for all."
>"Til we rally, raise, unite!"
>"All-One-God-Faith, All-One! Unite!"
>"Lives of great men all remind us we can make our lives sublime."
>"Life is real! Life is earnest! And the grave is not its goal."
>"Let us then be up and doing ... still achieving, still pursuing"
>"In all we do, let us be generous, fair & loving to Spaceship Earth and all its inhabitants."
>"We're ALL-ONE OR NONE! ALL-ONE!"
liveoneggs 2 hours ago
herbal tea is good for you, it seems
SwellJoe an hour ago
This study did not involve tea. Do you have links to studies showing herbal tea has similar effect? (Sincere question, I drink a lot of peppermint tea for its mild decongestant effects.)