Beetroot and Blood Pressure: How Nitrate, Bacteria, and Biology Shape Your Heart Health
Originally sent to subscribers on 10 December 2025
The Million Hour Memo
Here’s a question I've been asked this week....
“Can beetroot juice really lower my blood pressure, or is that just health hype?”
Here's what I want you to know.
It's not just about the beetroot.
It's also about the bacteria in your mouth that convert that beetroot into molecules that change the stiffness and age of your blood vessels.
Today I want to show you a loop almost nobody is taught.
Beetroot → Bacteria → Blood pressure.
Let’s dive in...
DATA
Where insight becomes impact
What I’ve been looking at this week…
Recent research from Exeter looked at something interesting.
Younger adults and older adults, side by side, all given the same beetroot juice for a period of time, then tracked for changes in blood pressure and oral bacteria.
Here's the headline.
Older adults in their 60s and 70s, taking daily beetroot shots for a couple of weeks, dropped their systolic blood pressure (that's the top number) by roughly 7 mmHg.
Younger adults in their 20s, taking the same drink, saw minimal change.
In the older adults, there was also a clear shift in species and number of specific oral bacteria.
A 7 mmHg reduction may not sound dramatic at first. Yet large population studies suggest that even a 2 mmHg drop in systolic blood pressure can cut heart disease and stroke risk significantly.
So 7 points is not a tweak. It's clinically meaningful. It might even mean the difference between taking medication or not, or at least reducing medication.
The Nitrate → Nitrite → Nitric Oxide Pathway
Let me walk you through the chemistry.
Dietary nitrate (NO₃⁻)
You eat vegetables like beetroot, rocket, spinach, celery, lettuce, fennel, kale. These plants naturally contain nitrate.Salivary “recycling”
About a quarter of that nitrate is actively taken up by your salivary glands and pumped back into your saliva.Oral bacteria convert nitrate → nitrite (NO₂⁻)
Specific bacteria on your tongue surface, especially species of Neisseria and Rothia, use nitrate as fuel. They change nitrate (NO₃⁻) to nitrite (NO₂⁻).Swallowing and stomach acid
You swallow that nitrite-rich saliva. In your acidic stomach, some of that nitrite is converted further into nitric oxide (NO).Nitric oxide in your blood vessels
Nitric oxide relaxes the smooth muscle in your vessel walls, widens your arteries, improves blood flow and reduces your blood pressure.
Think of it as WD40 for stiff pipes. Less resistance. Less pressure.
Your body also makes nitric oxide via a different route, from the proteins you eat that break down into amino acids, using nitric oxide synthase enzymes.
The challenge is that this enzyme system becomes less efficient with age, oxidative stress (like rusting of your cells) and chronic disease.
That is why this bacteria-mediated nitrate pathway becomes more important as you get older. You are effectively bypassing a sluggish enzyme system by using food plus bacteria instead.
So why did the older adults in the beetroot studies see bigger blood pressure changes than the younger adults?
A few key reasons:
Older adults usually start with higher baseline blood pressure and stiffer arteries, so there is more room for improvement.
Ageing appears to alter the oral microbiome, often reducing the helpful nitrate reducers.
When you provide consistent dietary nitrate, those helpful species are selectively enriched, and you see both a microbiome shift and a blood pressure shift.
DEVICES
Track it to hack it.
What I’ve been monitoring this week…
You know I always want you to move from guessing to knowing. So here's how to measure what matters.
Continuous blood pressure monitoring
For my data-loving clients, I like continuous monitoring more than occasional spot checks. Devices like the Hilo Band use optical sensors at the wrist plus pulse wave analysis, calibrated against a standard cuff, to measure blood pressure repeatedly across the day and night.
What I like about this kind of bracelet is pattern: you see what happens to your blood pressure during meetings, meals, exercise, flights and sleep. You can overlay your nitrate experiments on real life: did your pressure track lower on the days you had your beetroot?
You get insight into night-time blood pressure, which is strongly linked to long term heart attack risk.
Salivary nitric oxide test strips
These are test strips you tap on your tongue. They change colour depending on your levels of salivary nitrite, which reflects what your oral bacteria have been doing with dietary nitrate.
Studies comparing colour-change strips to lab-based assays suggest they correlate reasonably for salivary nitrite, although they are not a precise measure of systemic nitric oxide in your blood vessels. So they are useful biofeedback tools, not diagnostic tests.
How I use them in practice:
Check a baseline reading first thing in the morning, before food or brushing.
Then repeat 90–120 minutes after a nitrate-rich meal or beetroot shot.
Watch the direction of travel over a few days.
They can be very motivating. When someone sees their strip colour move after three days of more beetroot, the behaviour tends to stick.
Oral health and oral microbiome
Because this whole loop depends on your mouth, I also care about:
A good dental review if you have gum disease or bleeding.
In selected cases, an oral microbiome test to look at the balance between nitrate reducers and more aggressive bacteria.
We are still early with these tests, but they are already helping me personalise plans for many patients.
DECISIONS
From knowing to doing.
What this means for YOU…
Now for the part that really matters. What do you actually do with all this?
When it comes to blood pressure and nitrates, I like to use a simple framework.
Feed it. Seed it. Read it.
Feed the nitrate pathway. Seed the right bacteria. Read what happens to your numbers.
Let’s break that down.
1. FEED IT. Give your nitrate pathway something to work with
Most people talk about “eating more vegetables” as if that is specific - it is not. Here we are targeting a very particular group:
Nitrate-rich vegetables, which include:
Beetroot and beetroot juice
Rocket (arugula)
Spinach
Celery
Romaine lettuce
Fennel, chard, pak choi
Some herbs such as dill and coriander
Here's a realistic starting point:
Aim for one portion of high nitrate vegetables every day.
For many adults with raised BP and healthy kidneys, I often work towards the equivalent of 250–400 mg of nitrate per day from food or beetroot juice, because that is the range frequently used in trials.
Practical ways to do this:
A 70–150 ml beetroot shot once a day.
A nitrate salad of beetroot, rocket, spinach, celery, fresh herbs, olive oil.
Beetroot and fennel soup.
Who should be cautious:
If you have a history of kidney stones or established kidney disease, particularly oxalate stones, go gently.
If your blood pressure is already low or you are taking multiple BP medications, make sure you have medical supervision before layering in these strong vasodilating strategies.
2. SEED IT. Protect the bacteria that run your nitrate factory
This is the bit almost everyone misses.
If your mouth is the factory, antiseptic mouthwash is often the mass redundancy letter.
Here is what many people get wrong.
They commit to nitrate-rich foods, then use a strong antiseptic mouthwash twice a day that kills the very bacteria needed to convert nitrate to nitrite.
Studies show that antiseptic mouthwash can blunt or even reverse the blood pressure-lowering effect of dietary nitrate by wiping out helpful nitrate reducers.
So, some simple shifts:
Brush and floss as usual. Gum health still matters for your heart.
Stop all antiseptic mouthwash.
Pay attention to dry mouth - you need saliva for this system to work. Hydration, nasal breathing and checking medications that cause dry mouth all matter.
I often say to my patients:
“You're running a nitrate factory in your mouth. Don't sack the staff.”
3. READ IT. Track what your arteries actually do
The win here is not a more pink test strip or a greener smoothie. The win is a calmer artery.
So here's what I suggest:
Know your starting numbers. Use your blood pressure bracelet to capture a 14-day baseline.
Run a 4-week experiment.
Feed it: add your daily nitrate-rich vegetables or beetroot shot.
Seed it: protect your oral bacteria by stopping antiseptic mouthwash.
Use nitric oxide strips at baseline and after nitrate-rich meals to see if the pathway is waking up.
Read the results.
Repeat the same 14-day blood pressure profile at the end of 4 weeks.
Compare averages, not isolated readings.
Look at your bracelet data for any pattern shifts: lower average daytime BP, better night-time dipping, slightly lower resting heart rate.
If your blood pressure is in a high or dangerous range to begin with, all of this sits alongside medical treatment as additional leverage, not abandoning medication until levels have significantly and sustainably dropped.
CASE IN POINT
One of my patients.
Early 50s. Built a successful company. Spent more nights in hotels than at home.
His blood pressure had drifted from 135 systolic to 148 over three years. “Slightly high, but not too bad” as he put it.
He did not want to start medication yet, so we designed a precision experiment.
Daily 100 ml beetroot shot plus a rocket and spinach salad at lunch. Antiseptic mouthwash removed.
A continuous BP bracelet to track daily and nightly patterns. A 14-day profile before and after 4 weeks.
Result:
Average systolic BP moved from 148 to 132. Night-time blood pressure dipped more reliably. Resting heart rate nudged down.
He felt less “head heavy” at the end of the working day. No miracles. Just measurable, meaningful movement that aligned with what the research predicts.
It was enough, alongside other changes, to keep tablets off the table.
If you'd like to make decisions with precision based on your personal data and using devices that are specific for you, then book a private consultation and let's start to decode your health.
DIARY
Where you’ll find me…
Last week. Filming with ITV, interviews with journalists, writing commentary for media - just love getting messages of health that matter out there.
This week. Picking up my daughter from Uni - it's the download on the drive home that I look forward to the most!
Next week. Talking Longevity to leaders in London - my favourite workshop! I'll be sharing exactly these kinds of practical, data-driven strategies with founders and leaders who want their arteries to match their ambitions!!
DISTINCTION
A thought to pause on…
“Your blood pressure doesn't just follow your genes. It follows your greens.”
If your latest blood pressure reading has been creeping up, here's your nudge.
Before you only reach for a prescription, ask yourself:
How often am I feeding it, seeding it and reading it?
And if you want help designing a personalised nitrate plan and tracking its impact with precision, you know where to find me.