It's time for another Featured Optimizer post!

This week we caught up with Carl Parnell -- a tried and true biohacker and a man of many talents. 

Carl is in an acclaimed heavy metal band in the U.K, runs a neurofeedback center in his spare time, and is a professional digital marketer. 

Let's meet Carl.

Who are you? What do you do? 

My name is Carl Parnell and I'm from Reading, UK.

In my early teens I joined a band with some friends from school. 17 years later that band took us on some pretty serious adventures. I've also worked in games testing for Microsoft for 10 years (yes playing computer games and traveling the world with the band, don't hate me haha).

Recently, the band is on a much-needed hiatus and I've turned my attention to digital marketing. I'm now a digital marketing manager and I also created and released my own course. 

I'm also a certified neurofeedback practitioner on the side. I've been running a practice in my spare time over the last 3 years and it's been incredibly rewarding.

What's your backstory? When did you start taking your health and wellness seriously?

Being in a band has been an incredible experience, but it's also immensely stressful on the body and mind.

Sleeping somewhere different every night for months on end, eating terribly, getting a massive endorphin rush from playing then trying to sleep (it doesn't work).. all these things kept me in a pretty consistent fight or flight response and it was hard to maintain that sort of lifestyle in a healthy way.

That's what initially got me to start taking care of my health and wellness more seriously.

What was your biggest challenge in improving your health? How did you overcome it? 

I adore our health system in the UK, but for deeper, more holistic issues they simply aren't equipped with the knowledge, time or resources to help someone in my situation. Every time I went in for a test it would come back fine, even though I had this crushing fatigue, brain fog, and lack of focus and attention. It was only when I took on a Functional Holistic doctor that I finally got confirmation that there was actually something wrong with me.

The biggest thing I learned was to test, not guess, so I set to work running the tests that would show me exactly what was wrong. I finally confirmed I had adrenal fatigue, leaky gut, mercury poisoning, methylation issues among others!

It sounds like a lot but it's simply KNOWING that's the most powerful thing.

What's the ONE thing that has completely changed your life?

Not stopping until you find an answer, even if it's something you don't want to hear.

Had I given up trying to get answers from the doctors over here, I dread to think what state I'd be in right now! I'm so glad I persisted, found a great network of like-minded people and stuck it out and the results have been incredible.

Where did you hear about Natural Stacks? What did you try first? What has been your experience so far? 

I first heart about Natural Stacks on a podcast with Tim Ferriss 4-5 years ago. He was raving about CILTEP, especially how it was all-natural and I was suitably intrigued.

Back then my focus and attention were totally shot so I was trying a few supplements and nootropics.

Some were OK, others not so much. CILTEP was the first one that actually worked, no side-effects, and stayed consistent the whole time I took it.

When I combined it with a strong buttery coffee, my brain started to turn on again for the first time in years.

What does having a better brain mean to you?

It's pretty dang important! I found the most important reason for my brain switching back on is my commute. The drivers here in the UK are shocking (I'm sure it's the same elsewhere) and I have an hour+ drive to my office each day. I did find my focus would phase in and out during my drives and it worried me. Oh and I don't think I'd have been able to pursue a new career in marketing without a high performing brain!

If you could go back in time, what would you do differently?

Prioritize health and sleep over getting absolutely wrecked on tour (as boring as it sounds), seek a support group much much earlier and source a holistic doctor instead of going to my standard doctor 100% of the time.

What are some of the common mistakes people should avoid when working to improve their health?

I'd say failing to address the root cause of their issues.

A great analogy is a patient going to their doctors for foot pain. The doctor sends them away with pain killers. On closer inspection, it was a stone in their shoe causing the pain, by looking at the root cause and removing the stone, there is no need for pain killers. 

I chucked every supplement I could find down my neck trying to solve my energy issues but nothing worked until I found the root cause and began addressing that.

What foods, supplements and coffee do you use every day? 

Upon Waking:

I'll down a glass of water with salt, apple cider vinegar (ACV). Then I'll make some fresh organic coffee with rosemary (amazing for polyphenols) and blend with ghee, MCT, gelatinized Maca, exogenous ketones and cacao butter. This tastes AMAZING.

Followed by some Natural Stacks Vitamin D, adrenal cortex, pregnenalone (don't take these without testing first), licorice root and my fav...CILTEP.


It'll be something green, usually 4-5 different steamed veggies covered in thyme, rosemary, basil (extra polyphenols) with ghee, ACV, MCT, avocado and some super clean meat or eggs. I've started wrapping this in nori sheets for extra flavor. I love my Thorne 2-a-day multi, has my bases covered and I'll probably chuck down a Four Sigmatic Mushroom Coffee w/ Lions Maine (rocket fuel).


As evening approaches I'll have a similar meal, emphasis on vegetables and fats. I'll maybe have some jasmine rice or a sweet potato if I've exercised.


A few hours before bed I'll take some Natural Stacks MagTech and just after I'll have honey and ACV in hot water. This combo puts me OUT.

What have been the most influential books, podcasts, or other resources for your health and why?

The cliche opener would be The Power Of Now, but it was the first book to really change my outlook on a few things. The Mercury Diaries is a MUST for anyone that is, or suspects they may be dealing with mercury. 

Podcast-wise, Bulletproof Radio was the one that got me looking into my health properly 5 years back. The Joe Rogan experience has had some incredible guests over the years. Lately, Ben Greenfield and Dr. Rhonda Patrick have become mainstays in my feed. 

Where can people go to learn more about you?

If you're in the UK and want to try Neurofeedback you can check out more at

You can find me on Instagram too: carlosisis

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