The Tiny Powerhouse Behind Every Big Health Goal
There is a conversation happening at the forefront of longevity science right now, and I think it is one of the most important ones we can be having.
My recent exchange with Jen Scheinman, registered dietitian and Director of Science at Timeline Nutrition, opened my eyes to something I thought I already understood — and completely changed how I think about energy, aging, and healing from the inside out.
Most of us know the mitochondria as the powerhouse of the cell, a phrase we memorized in high school biology and promptly forgot. But what Jen helped me understand is that the mitochondria is so much more than an energy factory. It is the master communicator of the cell — regulating hormones, signaling when cells need to retire, and influencing everything from brain function to skin health to muscle strength. When your mitochondria are thriving, you feel it. When they are declining, you feel that too, often without knowing why.
And here is the part that stopped me: mitochondrial decline begins in your 30s. It happens to all of us, regardless of how well we eat or how often we exercise. The question is not whether it happens, but how well we support the body’s built-in repair mechanism — a process called mitophagy, where damaged mitochondria are recycled and replaced with healthy new ones. That cleanup system also declines with age, which is where urolithin A comes in. This postbiotic nutrient, found in small amounts in pomegranates, berries, and certain nuts, is what triggers that recycling process. The problem is that about 60% of us no longer have the gut microbiome needed to produce it on our own.
Why This Matters
Jen shared her own decade-long journey with Lyme disease, and something she said resonated deeply with me. It wasn’t one dramatic intervention that turned things around. It was finding a doctor who looked her in the eye and said: I believe you, and we are going to figure this out together. That moment of being truly seen and supported changed her trajectory entirely.
So much of what she shared connects to the broader conversation we keep returning to on this podcast. Our bodies have extraordinary self-healing intelligence built in, but that intelligence gets overwhelmed when we are depleted, chronically stressed, and running on damaged cellular foundations. Supporting the mitochondria is not a biohack or a trend; it is one of the most foundational things we can do to give our bodies the conditions they need to do what they were designed to do.
This Week’s Practice
A few simple places to start supporting your mitochondrial health:
Prioritize sleep above almost everything else. Cellular repair, including mitophagy, happens primarily during rest. If you are cutting sleep, you are cutting your body’s ability to clean house.
Eat a diverse whole food diet rich in polyphenols — berries, pomegranates, nuts, and colorful vegetables — to fuel both your gut microbiome and your cells.
Consider urolithin A supplementation. Timeline’s Mitopure is the most clinically studied form available. Start at 500mg and give it at least four months to feel the full effects. Mitopure now starts at $79 at timeline.com/HEALwithKelly
Advocate for yourself. If you have been dismissed by doctors, keep going. Find someone who believes you and is willing to get in the trenches with you.
Manage your stress load. Chronic stress is one of the primary triggers that allows dormant pathogens and dysfunction to take hold. Your nervous system and your mitochondria are deeply connected.
With love,
Kelly