Hello my friends and oxygen inhalers! This week we’re investigating the secrets of how to keep your microbiome young, how one small habit can reduce your risk of heart disease and I’ll take you through my high protein, high fiber daal-rice recipe!

The Oldest Woman in the World and Her Gut’s Secret!

Maria Branyas Morera didn’t just live long…she lived well.

When she passed away in 2023, she was 117 years and 168 days old. A true supercentenarian.

Naturally, scientists wanted to know: what made her so resilient?

Researchers at the Josep Carreras Leukemia Research Institute in Spain discovered her genetics gave her an edge…her cells aged more slowly, and she carried rare mutations that may have protected her from cancer. But lifestyle factors mattered too.

One clue stood out: Maria ate three yogurts a day.

Fermentation, fiber & longevity

Fermented foods like yogurt are rich in live microbes. They don’t just “add” bacteria; they encourage the existing good bacteria in your gut to grow and flourish.

That matters, because gut diversity is one of the strongest predictors of healthy ageing. A 2021 Stanford study showed that diets rich in fermented foods boosted microbial diversity and reduced inflammation. Another study found that people with the most unique microbiomes were healthier, more mobile, and lived longer.

Meanwhile, those with less diverse guts needed more medications and had higher mortality risk.

Your gut = a living forest

Think of your gut like a forest.
You don’t need to keep “importing” new animals (probiotics) every day. The forest already has a rich ecosystem…what it needs is nourishment to thrive.

Feed it the right foods, and the beneficial species multiply, keeping the whole system balanced and resilient.

What you can actually do (no guarantees about living to 100+ though!)

You don’t need three yogurts a day to borrow a page from Maria’s playbook. Here’s what the science suggests:

1. Feed your existing good bacteria.
   Forget constantly buying probiotics. Your gut already has trillions of friendly microbes..they just need the right fuel to flourish.
   

2. Eat diverse fibers daily.
   Each fiber feeds different species. Mix beans, lentils, oats, barley, apples, onions, garlic (you get the idea…) variety is key.
   

3. Include fermented foods.
   Yogurt, kefir, kimchi, sauerkraut, kombucha. Small daily servings can tilt your gut towards resilience.
   

4. Aim for 30+ plant foods a week.
   Backed by the American Gut Project, this “30-plants challenge” is strongly tied to higher microbial diversity.
   

5. Rotate, don’t repeat.
   Don’t default to the same spinach salad. Swap in rocket, kale, watercress. Microbes love variety.
   

6. Focus on the long game.
   Missed meals, travel, or a week of takeaways won’t undo everything. What matters is your overall dietary pattern.
   

Maria Branyas Morera’s secret wasn’t a magic supplement. It was a lifestyle that helped her microbes, and in turn, her microbes helped her.

You don’t need to keep adding more gut fads and funky routines to your system. You already house a powerful ecosystem…it just needs the right TLC.

Feed it well, and your gut will reward you with resilience that echoes across your body, from immunity to longevity.

P.S. This is exactly why I’ve spent the last two years engineering LOAM: a multi-fiber blend to keep your gut forest thriving even on the days when life gets in the way. Travel, skipped meals, late nights…LOAM is your insurance policy for feeding your existing good bacteria and keeping them strong. I cannot wait to share it with you in under a month so sign up here to get on the priority access waitlist:

P.P.S I’ll be giving people on the waitlist some very cool early exclusives too! ;) see you inside!

Cut Heart Disease Risk By Up To 50%!

Modern life isn’t exactly heart-friendly.

We sit for over 9 hours a day on average. Stress levels are at an all-time high, fueling chronic inflammation. And more than 50% of the food on our plates is ultra-processed…also linked to higher stroke risk.

No wonder heart disease remains the world’s leading cause of death, responsible for 1 in 8 deaths globally (WHO). Even more concerning: research from Oxford shows that today’s 50- and 60-year-olds are up to 1.5 times more likely to develop heart disease than their grandparents were at the same age.

But there is good news too: protecting your heart doesn’t just cut heart attack risk…it may slow ageing and even reduce dementia risk.

And surprisingly, one of the most overlooked factors in heart health starts not in your chest, but in your mouth.

The gum–heart connection

Have you ever noticed a little streak of blood in the sink after brushing? Well it may not be just a dental issue but a warning sign for your heart.

Gum disease (gingivitis and periodontitis) is caused by bacteria-laden plaque triggering chronic inflammation. This inflammation doesn’t stay in your mouth but rather spills into the bloodstream, contributing to atherosclerosis (the narrowing of arteries that contributes to heart attacks and strokes).

A 2025 study presented at the American Stroke Association found that people who floss at least once a week had:

• 44% lower risk of cardioembolic stroke (caused by clots from the heart)
  

• 12% lower risk of atrial fibrillation (an irregular heartbeat that raises stroke risk)
  

Even after accounting for brushing habits, flossing seemed to carry unique protective benefits.

Correlation ≠ causation, of course. People who floss may also exercise more or eat better. But the weight of evidence now suggests oral health is a surprisingly powerful piece of cardiovascular prevention.

The European Society of Cardiology has gone so far as to suggest that routine dental screening and gum care could help prevent first and subsequent heart events.

Practical takeaways for you

You already know the “boring” classics: don’t smoke, move daily, eat more plants, sleep well, drink less alcohol. But here are a few heart–mouth hacks worth adding:

1. Floss once a day (minimum once a week).
   Think of flossing as “artery insurance.” It takes 2 minutes, costs pennies, and could protect your heart.
   

2. Don’t ignore bleeding gums.
   Bleeding after brushing is never “normal.” Book a dental check-up; gum inflammation might be your body’s red flag.
   

3. Brush twice a day, minimum 2 minutes.
   Electric toothbrushes are consistently shown to reduce plaque and gingivitis better than manual ones.
   

4. Chew your way to health.
   Crunchy, fibrous foods (apples, carrots, celery) help clean teeth and feed your gut microbiome; another indirect win for heart health.
   

5. Treat dental visits like health check-ups, not optional extras.
   Just as you wouldn’t skip a cholesterol test, don’t neglect your gums. Yes I know dental visits can be expensive…but heart troubles can be even pricier!
   

Your mouth is the front line of your body’s inflammatory defences. Neglect it at your own peril! I’m telling you this as someone who was too lazy to floss for years…if you’ve got time to scroll brainrot Tiktok videos you have no excuse to skip flossing! (this is coming from a reformed brainrot doom scroller) 

It’s not just about saving your smile. It might just save your life.

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The High-Protein, High-Fiber Dal That Loves Your Gut

If you’re looking for a meal that keeps your gut microbes happy and your muscles fuelled, this one’s for you. A humble bowl of dal-spinach rice…but elevated to microbiome superfood status.

One portion of this dish delivers around 40g of protein and 30g of fiber; perfect for satiety, stable energy, and feeding your gut garden.

Ingredients (for 4 servings)

• Rice – 200g (about 1 cup, uncooked)
  

• Masoor dal (red lentils) – 65g (⅓ cup)
  

• Mung dal (split yellow mung beans) – 65g (⅓ cup)
  

• Moth beans – 65g (⅓ cup), soaked overnight
  

• Frozen spinach – 250g
  

• Onion – 1 medium, chopped
  

• Garlic – 4–5 cloves
  

• Fresh ginger – 2–3 cm piece
  

• Green chillies – 2–3 (or swap for ½ tsp black peppercorns if you prefer milder heat)
  

• Cumin seeds – 1 tsp
  

• Ghee – 2 tbsp (or olive oil if vegan)
  

• Salt – to taste
  

• Natural yogurt – to serve (optional, skip if dairy-free)
  

Step-by-step guide

1. Wash & soak:
   Rinse rice and dals thoroughly. Soak moth beans overnight (but can skip if needed)
   

2. Cook the base:
   In a pressure cooker (or Instant Pot), combine rice, masoor dal, mung dal, and soaked moth beans with 4–5 cups of water. Cook for 3–4 whistles (or ~15 mins on high pressure). Set aside.
   

3. Prep the spinach mix:
   In a wide pan, heat 2 tbsp ghee. Add cumin seeds until they splutter.
   Stir in ginger–garlic paste and green chillies. Fry for 2 mins.
   Add chopped onion. Cook until golden (3–4 mins).
   Stir in spinach, cook 4–5 mins until wilted.
   

4. Combine & season:
   Mix the spinach masala with the cooked rice-dal blend. Add salt to taste.
   

5. Serve:
   Ladle into bowls. Add a dollop of yogurt if you tolerate dairy.
   

Smart swaps

• Low-FODMAP: Swap onion & garlic for hing (asafoetida) powder + extra ginger. Use small amounts of mung and red lentils (better tolerated than chickpeas/kidney beans).
  

• Vegan: Use olive oil or avocado oil instead of ghee.
  

• Gluten-free: This dish is naturally gluten-free.
  

• Spice-sensitive: Replace chillies with black pepper or omit.
  

 Gut health benefits of key ingredients

• Masoor dal, mung dal & moth beans: Rich in soluble and insoluble fibers that feed different microbes. Also packed with plant protein. Fiber here helps boost short-chain fatty acid (SCFA) production; critical for gut lining integrity.
  

• Spinach: High in polyphenols and prebiotic fibers (including arabinoxylans). Supports beneficial bacteria like Bifidobacteria.
  

• Onion, garlic, ginger: Natural prebiotics (fructans in onion/garlic; gingerol in ginger). Help balance microbial populations, though can be swapped out if you’re low-FODMAP.
  

• Rice: Provides resistant starch (especially if cooled and reheated), which fuels butyrate-producing bacteria.
  

• Cumin, chillies/pepper: Contain bioactive compounds that can modulate gut microbes and reduce inflammation.
  

• Ghee: Source of butyrate (the same SCFA your gut bugs produce), which supports colon health (but a very modest amount…it just tastes damn good!)

• Yogurt (optional): Fermented food that supplies live cultures. You don’t need to add probiotics daily…focus on feeding the good bacteria you already have with diverse fibers. Yogurt just adds another layer of support (served as a side dish)

This dal-rice-spinach bowl is comfort food that also becomes functional food. It nourishes your existing gut bacteria with a spectrum of fibers and polyphenols, while packing in muscle-friendly protein.

Cook a batch once, and you’ve got four powerhouse meals ready to go (btw if you’re a visual learner...check my instagram page for a video of me making this!)

👋 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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