The Surprising Blood Pressure Hack Hiding in Your Fridge

If I told you there’s a legal, affordable, completely kitchen-friendly “performance enhancer” that can open up your blood vessels, improve oxygen delivery and lower your blood pressure…
… you’d probably assume I’m trying to sell you something questionable from the dark corners of the internet.

But no… the answer is beetroot. The same vegetable that stains your chopping board and makes you briefly question whether you’re bleeding internally the next day on the toilet.

A meta-analysis of 75 randomised controlled trials covering 1,800+ people found that simply increasing your dietary nitrate intake (the compound found in beetroots and leafy greens) measurably lowers blood pressure.

Here’s what researchers found:

• For every 1 mmol/day increase in dietary nitrate:
  Systolic BP ↓ 0.48 mmHg
  Diastolic BP ↓ 0.12 mmHg
  

The benefits plateau around 8 mmol/day, which you can hit with:

• 150 ml beetroot juice, or

• a big serving of spinach, rocket, kale, Swiss chard etc.
  

And that dose was associated with a 10–20% reduction in cardiovascular events in long-term data.

All from plants you can buy for £1.50 or a couple of dollar.

Why this dietary voodoo (nitrates) works 

Your body has a clever three-step nitric oxide assembly line:

1. You eat nitrate-containing foods so nitrate enters your bloodstream.

2. Oral bacteria convert nitrate to nitrite

3. Nitrite becomes nitric oxide (NO) and NO relaxes and widens blood vessels, reduces inflammation, improves oxygen delivery and supports exercise efficiency.

The Nitric Oxide killer 

Whatever you do… avoid using antiseptic mouthwash right before or after eating high-nitrate foods.

It wipes out the very oral bacteria needed for the nitrate to nitrite conversion.

(This is also one of the most underrated reasons mouthwash can increase blood pressure in some people.)

Brush your teeth normally and just skip the nuclear mouth-rinse (unless you’re required to use this as directed by your dentist for a specific condition!)

Where to get nitrates

Top nitrate-rich foods:

• Beetroot Juice

  150 ml = ~8 mmol nitrate
  

• Leafy Greens: spinach, rocket, kale, lettuce, chard
  = 2–6 mmol per serving (Even easier if you throw them in soups, omelettes or sandwiches.)

• Root Vegetables: beetroot, turnips, radishes

  Great nitrate carriers + fiber.

• Celery & Fennel

  Often overlooked, naturally high in nitrates and very hydrating.

Practical tips

• Add ½ cup beetroot juice to your morning routine 2–3x per week… no need to chug daily.

• Throw a handful of spinach or rocket into any meal; it disappears into pasta, eggs, stir-fries, and smoothies.

• Swap your side salad for beetroot + walnut salad once a week.

• Skip antiseptic mouthwash for at least 2 hours around meals.

• If you exercise, try eating nitrate-rich veggies 2–3 hours before your workout for an oxygen-efficiency boost.

You could do much worse than adding a few extra vegetables that taste like the earth.

Let me know if you try this… especially if your pee turns pink. That’s half the experience.

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Free Invite To A Live Event With Me!

I’m throwing an online live event where I will be discussing various health topics that I cover in my book… details at the end of this segment!

Several years ago I saw a patient in clinic who sheepishly told me that they’d experienced some rectal bleeding. On further quesitoning it transpired that this bleeding had been accompanied by constipation and the symptoms had been going on for a few months at this point.

They said they were too embarrassed to see a doctor and to talk about their bowe symptoms… and that the subject was too awkward to even bring up to their partner or family.

After an examination I noticed a large mass in their abdomen. I ordered a same day CT scan which confirmed my fears… an advanced, metastatic colorectal cancer.

But this was one of many “awkward”, “taboo” or “embarassing” topics that shouldn’t be mired in shame and secrecy. Women’s health, periods, menopause, prostate issues, erectile dysfunction, mental health, dodgy guts, weird poops, death, cancer and more… the list is endless.

In early 2023, I was again reminded of exactly why I do what I do online and why this book matters so much. A woman stopped me at Heathrow airport to tell me that one of my videos about breast cancer had changed her life. I can’t begin to describe how motivating moments like these are.

So in mid 2023 I set about writing “This Is Vital Information”. A book that shines a light on these topics that are shunned and a way to provide actionable insights and tips to the topics we’re too embarrassed to talk about 

This book is my way of giving you the most powerful, evidence based tools you need to advocate for yourselves and others.

As a bonus if you pre-order the hard copy of the book here:

You also get access to my live event here :

Can’t wait to see you there!

Travel Hack To Save Your Gut! 

I’ve been travelling a lot recently, and I’ve realised something:
The first casualty of travel isn’t your sleep or your diet, your exercise routine…

It’s your gut.

Your bowels take one look at a different time zone, strange food, fluorescent airport lighting, and say, “absolutely not.”

Travel is one of the biggest disruptors of our internal rhythm… not just for your brain, but for your microbiome, motility, hormones, and even your vagus nerve.

Your gut has a circadian clock too

We talk a lot about circadian rhythms as if your brain is the star of the show.
But every organ including your digestive tract runs on its own internal clock.

Your gut bacteria also follow day–night cycles. Yep… your microbes have a bedtime and they’re very moody when you mess with it.

When travel disrupts this rhythm, a few things happen:

1. Reduced motility

Your intestines rely on circadian signalling to coordinate peristalsis. Jet lag means a sluggish gut. This is why many people suddenly go from regular to poop schedules being MIA

2. Compromised nutrient absorption & repair

Gut lining repair is an overnight process. If you shift that schedule, the system gets confused and efficiency drops.

3. Lower microbial diversity

Circadian disruption alters microbial activity patterns. Think of it like trying to run a restaurant where half the staff show up at midnight. 

The vagus nerve: your gut–brain bluetooth

Travel stress also hits the vagus nerve… the communication superhighway between gut and brain.

When stress is high (tight connections, delays, mysteriously expensive airport sandwiches), vagal activity drops. Low vagus tone means reduced motility + worsened digestive symptoms.

Chronic stress also reduces beneficial bacteria, loosens the gut barrier, and generally makes your insides behave like a toddler in a supermarket.

So what can you actually do when you travel?

Here are simple, realistic, evidence-based habits I personally follow (or at least try to follow) when I’m hopping across time zones:

1. Anchor your circadian rhythm with light

Morning sunlight within the first hour of waking

• Avoiding bright blue light late at night allows your internal clock to recalibrate faster. This alone improves gut motility.

2. Eat at consistent times

Your gut LOVES predictability. If you normally eat at noon but suddenly eat at 4pm, your microbes will react like they’ve been stood up. Aim to keep meal timing roughly consistent.

3. Prioritise fiber (the bloat-friendly kind)

A disrupted microbiome needs regular, fermentable fuel. Fiber supports short-chain-fatty-acid production, motility, and microbial stability… all things that tank during travel.

Hydration + fiber + movement is the holy trinity of travel digestion.

4. Stress management (microbes hate stress as much as you do)

Deep breathing, slow exhales, a 5-minute meditation… anything that activates the parasympathetic system and restores vagus tone.

This directly improves digestion, motility, and abdominal comfort.

5. Move more than you think you need to

Walks after meals, stretching, hotel-room mobility sessions

Movement signals the gut to wake up again.

My personal travel non-negotiable:

I take LOAM everywhere; especially the travel-friendly stick packs.

Unlike other fiber supplements, LOAM uses six different prebiotic fibers arranged for modified release across the entire digestive tract.
That means:

• steady fermentation

• better microbial stability

• less of the “help, nothing is moving” phenomenon

• and a gut that behaves more predictably even when your time zone doesn’t
  
  

When everything else in my routine collapses, LOAM stops my gut from filing a formal complaint.

If you’re travelling soon, remember your microbiome doesn’t hate you… it just wants consistency, a little sunlight, some fiber, and fewer airport croissants.

(…Okay, maybe one croissant.)

👋 Who are you again? I’m Karan Rajan - a doctor and curious explorer of all things health and wellness. I host the Dr Karan Explores Podcast and have written two books "This Book May Save Your Life" and "This Is Vital Information" (you can pre-order it now!) and have just founded a microbiome company, LOAM Science  to create the best fiber product in the world!

Every Sunday, I share 3 interesting things about health, life and science to make your life easier, healthier and happier. (Disclaimer: I’m more your friend with health benefits. None of this is medical advice.) 

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