Random Issue: Vagus Nerve, Intermittent Fasting, 9/11 & More
What's on my mind and how it may help you
👋Hello, my friend. This week, I was all over the place — literally and figuratively. The highlight might have been chatting with Jesse Cole, owner of the Savannah Bananas, as we waited for our delayed flight to Laguardia (him heading up to do Jimmy Fallon, me heading up… NOT to do Jimmy Fallon!). Anyhow, lots on my mind at the moment — from the vagus nerve to 9/11 — but no obvious theme, so I present to you: The Random Issue.
Let’s get into it!
💪Peloton x Intentional Wisdom
Before we get started………. 🚨New challenge starts today!
Simple. Who can work out for the most minutes this week? Starts…. NOW.
Not in the group yet? Want to shame me publicly by showing off how much more disciplined you are? Great. Let’s see it!
If you’re not on Peloton, don’t worry, the link will give you 60 days free access to all of their workouts. I like the strength workouts, but I also use the app to track walking and I usually work in at least one Bike and Tread workout per week. Join me!
🧠The Vagus Nerve: Why I’m Paying Attention
Both Tim Ferriss and Andrew Huberman did recent episodes on the vagus nerve, and I’ve been digging into them. Here are a few highlights that stood out to me:
What is it?
The vagus nerve (cranial nerve X) is the longest cranial nerve in the body.
It runs from the brainstem through the neck into the chest and abdomen, connecting to the heart, lungs, and digestive tract.
It carries both sensory and motor fibers, making it a core part of the parasympathetic nervous system—helping regulate heart rate, breathing, digestion, inflammation, and mood.
Why it matters:
Helps regulate heart rate variability (HRV)—a key marker of health and longevity.
Plays a big role in controlling inflammation, which ties to almost every chronic disease.
Ways to stimulate it (non-invasive):
Breath: physiological sighs, extended exhales, slow controlled breathing
Voice: humming, chanting, singing
Body: neck stretches, massage, yoga
Environment: cold exposure, nature immersion
Lifestyle: sleep, exercise, diet
From the Ferriss episode:
Clinical devices are already being used to treat Crohn’s and rheumatoid arthritis.
Vagus nerve stimulation (VNS) lowers harmful inflammation without shutting down the immune system completely.
Ferriss highlighted the importance of matching the nerve target to the disease mechanism—not just stimulating broadly.
👉 Personally, I’m most interested in vagus nerve stimulation for two things:
Immune support
Improving HRV (since I track HRV daily with Whoop).
Huberman pointed out that people who practice the physiological sigh multiple times a day see higher HRV. I’ve started experimenting with more long exhales throughout the day to see how that impacts me.
For more background, here’s my 2021 post on HRV: The Most Important Metric You’re Not Tracking (HRV).
What I’m doing:
Trying to work in some intentional breathwork a few times per day (Whoop has a great little built-in exercise for this on their app)
Considering checking out one of the auricular vagus nerve stimulation devices, which supposedly can help with sleep, mood, inflammation, and other things. I actually just had ChatGPT work up a report for me on these devices… ping me if you want me to send that your way.
Reflections on 9/11
This week marked the 24th anniversary of 9/11. That day was a formative experience in my life. I was in lower Manhattan when the towers came down, and it still brings up a lot of emotions for me.
I wrote more deeply about my experience and key takeaways in this piece: Everything Changed in an Instant (9/11 Reflections).
Everyone’s Sick Right Now
Back-to-school season means everyone’s bringing home sore throats, coughs, and runny noses. I flagged this last year, but it’s worth repeating with a little more detail:
NAC (N-acetylcysteine): Huberman has pointed to solid evidence that NAC helps reduce both the incidence and severity of respiratory infections. It supports the body in making glutathione, which is a powerful antioxidant for immune defense.
Zinc: Supplementation seems most effective when taken at the first sign of symptoms or when you’re around sick people. Several studies suggest it can shorten the duration of a cold.
Together, NAC + zinc is a combo I keep handy this time of year. I’ve been hitting them both this week as I’ve got several sick kids running around my house!
Two other tools I’ve been leaning on:
Huberman’s cold & flu episode → breaks down what’s worth trying and what’s not.
PROFI nasal spray → creates a protective barrier inside the nose to block germs. I used it on my flight to NYC this week surrounded by coughing and sneezing passengers. First heard about it on Ferriss.
Current Experiments
Fasting: Right now, I’m eating from about 11am–7pm (so ~16 hours fasted daily).
Low-carb / high protein: Not calling it keto yet, but moving in that direction.
CGM: Tracking glucose closely.
DEXA + VO2 max: Tests scheduled later this month to get a new baseline.
Bloodwork: Another full draw coming up in October (100+ biomarkers). I use Function for this. Use my code if you sign up for extra savings.
So far, fasting and lower carbs have me down a couple pounds and feeling good. I’m curious to see how the testing lines up with what I’m noticing.
That’s it for today - I told you it was random! But before you go…
Content Diet
Here are a few (hopefully nutritious) items you might consider for your own content diet this week:
🎧 Tim Ferriss – Vagus Nerve Stimulation: Credible vs. Bogus (#824)
Ferriss & Dr. Kevin Tracey dive into the science and stories behind vagus nerve stimulation—covering inflammation, autoimmune disease, and some pretty wild personal case studies.🎧 Andrew Huberman – Control Your Mood with the Vagus Nerve
Huberman explains how the vagus nerve regulates mood, stress, and HRV, and walks through practical tools—like sighing, humming, and cold exposure—that anyone can try at home.📖 Book I’m currently reading… Hampton Sides – Hellhound on His Trail
A fast-paced narrative about MLK’s assassination and the manhunt for his killer. Striking parallels to more recent political assassinations.📝 Everything Changed in an Instant (9/11 Reflections)
My account of being in Manhattan that day, and what I’ve carried with me since.📝 The Most Important Metric You’re Not Tracking (HRV)
A closer look at HRV as a key health metric and how to improve it.🎧 Andrew Huberman – Cold & Flu: What Actually Works
A science-based look at which supplements and behaviors actually help when everyone around you is sick.
Thanks for reading. Have a great week!
Greg