Episode 103
Mitochondria Matter: The Story of Aging
The Mitochondria Problem: Why These Tiny Powerhouses Shape How We Age
Many people suddenly talk about mitochondria. You hear them in political speeches, on podcasts, and across social media. RFK Jr said he can “see” kids with weak mitochondria just by watching them walk through an airport. Others claim special diets or powders can “fix” aging by supercharging these organelles.
However, most of that chatter misses the actual science.
This post breaks down what mitochondria do, why they matter for aging, and how you can keep them healthy. No hype. No detox teas. Just biology you can use.
What Are Mitochondria?
Every cell in your body contains tiny structures called mitochondria. They act like miniature cells living inside your larger cells. Each mitochondrion even has its own DNA.
Mitochondria divide independently from your regular cells.
They manage your energy, converting glucose to ATP
Finally, mitochondria keep your organs working.
You inherit all your mitochondria from your mother, which is why scientists use mitochondrial DNA to trace ancestry.
How Did We Get Mitochondria? (A Very Old Story)
About 1.5 billion years ago, a simple cell swallowed a bacterium and refused to digest it. Instead, they formed a partnership.
The bacterium supplied energy.
The host cell provided safety.
That partnership became the mitochondrion. Every person alive today runs on that ancient deal.
What Do Mitochondria Do All Day?
Mitochondria take glucose from your food and convert it into ATP — the energy your body uses to move, think, heal, and grow. This process runs every second of your life.
You cannot swallow ATP and get more energy. ATP supplements don’t work. Only your mitochondria make the usable fuel your body needs.
Why Young Mitochondria Work So Well
Young mitochondria act like teenagers. They run fast, bounce back quickly, and handle stress with ease. Cells constantly recycle old mitochondria through a process called mitophagy. This system works beautifully in childhood.
Fresh mitochondria power:
- strong muscles
- sharp thinking
- fast recovery
- healthy metabolism
When mitophagy runs smoothly, you feel energetic and resilient.
What Happens When Mitochondria Age
Aging slows everything down. Mitochondria begin to leak more “exhaust,” build up mutations, and lose efficiency. Damaged ones don’t get removed as well, because mitophagy weakens with age.
Unfortunately, mitochondria do something worse than slow down:
They fuse with healthy mitochondria.
Imagine pouring spoiled milk into a fresh gallon. The whole jug goes bad. Aging mitochondria do the same thing inside your cells. They spread dysfunction to the healthy ones.
How Aging Mitochondria Cause Trouble
As mitochondria fail, they change how cells function. They send distress signals back to the nucleus that alter gene expression. These messages push cells toward inflammation, stress, and survival pathways that your body normally keeps quiet.
Even more concerning, changes in mitochondrial shape — too much splitting (fission) and not enough merging (fusion) — appear in both aging and cancer. These shifts support tumor growth, help cancer cells spread, and make some treatments less effective.
Aging mitochondria increase the risk of:
- brain fog
- muscle fatigue
- slower recovery
- heart strain
- metabolic slowdown
- cancer-friendly environments
Mitochondria sit at the center of how we age.
Why “Mitochondrial Booster” Supplements Miss the Mark
Plenty of supplements promise to “repair” mitochondria. Many sound exciting:
- NAD boosters
- Urolithin A
- peptides
- antioxidant stacks
However, evidence in actual humans remains limited.
NAD boosters don’t show meaningful anti-aging benefits.
Urolithin A can help with muscle endurance, but doesn’t reverse aging.
Antioxidant megadoses may even interfere with exercise benefits.
People want a miracle switch. We don’t have one.
What Does Improve Mitochondrial Health
Good news: the basics still win. And they outperform supplements every time.
1. Resistance Training
Your muscles grow new mitochondria in response to lifting weights or doing body-weight exercises.
2. Zone 2 Exercise
This “comfortably challenging” aerobic zone trains your body to use oxygen better. You can talk, but you can’t sing.
3. Sleep
Your body repairs mitochondrial damage at night. Poor sleep means poor repair.
4. Mediterranean Diet
Whole foods, plants, nuts, fish, and olive oil protect mitochondria from inflammation and stress.
5. Treating Metabolic Disease Early
High blood sugar, high LDL, and high blood pressure destroy mitochondria faster than anything else.
Why Diet Tribes Get Mitochondria Wrong
Some diet influencers insist that insulin resistance is the One True Cause of aging and that keto or carnivore diets fix it all. That was tested in high-quality metabolic ward studies.
It failed.
Low-carb diets did not outperform other diets when calories and protein were controlled. Fat loss was the same. Metabolism behaved the same. Insulin wasn’t the magic dial.
Mediterranean-style eating continues to show the strongest data for longevity.
Alcohol Ages Mitochondria Fast
Your liver breaks down alcohol by generating large amounts of oxidative stress. That stress directly damages mitochondrial DNA, mitochondrial enzymes, and mitochondrial membranes.
It also disrupts their normal fuse-and-divide rhythm, which accelerates aging inside your cells. The hangover fades, but the mitochondrial damage does not.
Bringing It All Together
Mitochondria are real, essential organelles — not a buzzword. Yet some people use the term “mitochondria” the same way Deepak Chopra uses the word “quantum": to describe everything and explain nothing.
Here’s the truth:
When mitochondria age, you age.
Driving inflammation.
Increasing cancer risk.
Slowing your metabolism.
They weaken your heart and muscles.
Finally, they cloud your thinking.
If we’re going to blame mitochondria for aging, let’s at least understand them — and learn how to keep them healthy.
Strength training, aerobic exercise, sleep, nutrition, and treating metabolic disease remain the most powerful tools we have.
Your mitochondria are trying their best.
Help them do their job.
REFERENCES
1.Somatic Mutations of Mitochondrial DNA in Aging and Cancer Progression.
Lee HC, Chang CM, Chi CW. Ageing Research Reviews. 2010;9 Suppl 1:S47-58. doi:10.1016/j.arr.2010.08.009.
2. Mitochondrial DNA Mutations in Ageing and Cancer.
Smith ALM, Whitehall JC, Greaves LC.Molecular Oncology. 2022;16(18):3276-3294. doi:10.1002/1878-0261.13291.
Smith AL, Whitehall JC, Bradshaw C, et al. Nature Cancer. 2020;1(10):976-989. doi:10.1038/s43018-020-00112-5.
4.Understanding the Impact of Mitochondrial DNA Mutations on Aging and Carcinogenesis (Review).
Kobayashi H, Imanaka S International Journal of Molecular Medicine. 2025;56(2):118. doi:10.3892/ijmm.2025.5559.
5.Mitochondrial Dysfunction and Oxidative Stress in Aging and Cancer.
Kudryavtseva AV, Krasnov GS, Dmitriev AA, et al. Oncotarget. 2016;7(29):44879-44905. doi:10.18632/oncotarget.9821.
6.Role of Mitochondrial Dysfunction in Cancer Progression.
Hsu CC, Tseng LM, Lee HC. Experimental Biology and Medicine (Maywood, N.J.). 2016;241(12):1281-95. doi:10.1177/1535370216641787.
7. Mitochondrial Dysfunction and Mitochondrial Dynamics-the Cancer Connection.
Srinivasan S, Guha M, Kashina A, Avadhani NG. Biochimica Et Biophysica Acta. Bioenergetics. 2017;1858(8):602-614. doi:10.1016/j.bbabio.2017.01.004.
8.Dysregulation of Mitochondrial Function in Cancer Cells.
Awad AMAM, Abdul Karim N. International Journal of Molecular Sciences. 2025;26(14):6750. doi:10.3390/ijms26146750.
Moghaddam SJ, Savai R, Salehi-Rad R, et al. American Journal of Respiratory and Critical Care Medicine. 2024;210(5):548-571. doi:10.1164/rccm.202406-1168ST.
10. Mitochondria in Oxidative Stress, Inflammation and Aging: From Mechanisms to Therapeutic Advances.
Xu X, Pang Y, Fan X. Signal Transduction and Targeted Therapy. 2025;10(1):190. doi:10.1038/s41392-025-02253-4.
Transcript
>> Dr. Terry Simpson: There's been a lot of talk about mitochondria
Speaker:lately. You had RFK Jr claiming as he walked
Speaker:through an airport he can see kids who are
Speaker:mitochondrial challenged. Now, RFK Jr. Unless he's
Speaker:developed a superpower to see inside living cells
Speaker:at 40 yards past TSA, no, you can't diagnose that.
Speaker:On the other end of the spectrum, you have Peter
Speaker:Attia, the current longevity guru of billionaires,
Speaker:doing three hour podcasts on mitochondrial decline
Speaker:and longevity, all while hawking some AG1. And in
Speaker:between, there's an entire wellness universe
Speaker:selling mitochondrial detox powers, peptides,
Speaker:resets, cleanses, and basically everything except
Speaker:mitochondrial reality. So why are we talking about
Speaker:them? Because it turns out mitochondria are, are
Speaker:the reason we age, get old and lose our health
Speaker:span. So today we are going to talk mitochondria
Speaker:reality and why mitochondria matter, what they do,
Speaker:how we age, and what you can do to keep them
Speaker:really healthy without buying powdered unicorn
Speaker:horn from the Internet. And, uh, please don't be
Speaker:like RFK Jr. Let's stick with the science. Today
Speaker:we're making sense of the madness of mitochondria.
Speaker:I'm Dr. Hi, I'm Terry Simpson, your chief medical
Speaker:explanationist. And this is Forku Fork University,
Speaker:where we bust myths, make sense of the madness,
Speaker:um, and explain that complicated world of food and
Speaker:medicine without the woo m. Inside every single
Speaker:cell of your body, except for red blood cells,
Speaker:live tiny structures called mitochondria. They're
Speaker:like their own little organ, and they behave like
Speaker:a mini cell inside your own body. They have their
Speaker:own set of DNA separate from the cell's DNA. They
Speaker:divide independently and they act independently.
Speaker:But what they are really important for is they run
Speaker:the energy production of your cell and your life.
Speaker:By the way, you inherit mitochondria from your
Speaker:mother, which is why mitochondrial DNA is so
Speaker:useful for tracing ancestry. And, and because the
Speaker:mitochondrial DNA is pretty hardy, we can actually
Speaker:get mitochondrial DNA almost from fossils. About a
Speaker:billion and a half years ago, a, uh, primitive
Speaker:cell swallowed a bacteria and instead of ingesting
Speaker:it, they became symbiotic. One saying, you make
Speaker:energy and I'll keep you safe. And that swallowed
Speaker:bacteria and became the forerunner of what we call
Speaker:mitochondria today. But more important, that
Speaker:ancient merger between a single celled organism
Speaker:swallowing another that became symbiotic was the
Speaker:start of complex life, making all of us possible.
Speaker:Now, what do mitochondria m do without the
Speaker:biochemistry? Here's a version that won't give you
Speaker:flashbacks to college Biochem Mitochondria take
Speaker:glucose from your food, from your body and turn it
Speaker:into ATP, the energy molecule your cells use to
Speaker:lift your weights, pump your heart, fire a neuron,
Speaker:whether it be in your brain or in your toe, and
Speaker:heal tissue. Now, ATP supplements exist and they
Speaker:don't work. If ATP worked orally, TikTok would be
Speaker:full of glowing people. The only way you can
Speaker:really get ATP usefully is by having your
Speaker:mitochondria make it from the universal currency
Speaker:of metabolism, glucose. Now there are, ah, young
Speaker:mitochondria and there are old mitochondria. And
Speaker:here's the difference. Young mitochondria are like
Speaker:my teenage son. He's energetic, he's fast, he's
Speaker:resilient, annoyingly efficient. And old
Speaker:mitochondria, they kind of remind me of that 14
Speaker:year PhD student who knows where every coffee shop
Speaker:on campus is, drinks too much caffeine, has
Speaker:written absolutely nothing on his dissertation
Speaker:since 2011, but likes to flirt with the co eds and
Speaker:wants to have that fatherly figure too. Well, you
Speaker:know, old mitochondria are slow, but they leak
Speaker:oxidative waste, lots of inflammatory tissues,
Speaker:they cause mutations, they become unreliable. And
Speaker:here's the kicker. Mitochondria constantly fuse
Speaker:with one another and they divide. And if a damaged
Speaker:mitochondria fuses with a healthy one, it's like
Speaker:pouring spilled milk into a fresh gallon of milk.
Speaker:You don't get half fresh milk, you don't get all
Speaker:fresh milk. You get one giant ruined bit of milk.
Speaker:That's why mitochondrial aging accelerates
Speaker:cellular aging. Your body has a way to clean up
Speaker:old mitochondria. It's called mitophagy. Sounds
Speaker:like autophagy, but it's specific to mitochondria.
Speaker:And it's a process where our cells have this great
Speaker:recycling process where they clean out old damaged
Speaker:mitochondria, replacing them with new one. But as
Speaker:we age, the ability to clean out those old
Speaker:mitochondria become older, the cleanup trough
Speaker:becomes kind of tired. Broken mitochondria stay in
Speaker:the system, dysfunction spreads, and the decline
Speaker:is one of the fundamental drivers of aging. Now,
Speaker:aging mitochondria don't just underperform, they
Speaker:cause mischief. They leak oxidative stress
Speaker:molecules. They confuse normal cell signaling,
Speaker:triggering retrograde signaling, which is
Speaker:distressed messages back to the nucleus of the
Speaker:cell, changing gene expression and in dangerous
Speaker:ways. Meaning that can actually promote pathways
Speaker:that cancer cells use. Increased resistance to
Speaker:chemotherapies and other therapies. It supports
Speaker:metastasis and it drives Chronic inflammation. So
Speaker:when the balance of fission and fusion fall apart,
Speaker:mitochondrial chaos becomes cellular chaos. Aging
Speaker:mitochondria aren't innocent. They actively
Speaker:sabotage tissue. Let me give you an example. In
Speaker:the brain. Now, your brain depends on mitochondria
Speaker:more than almost any other organ. The neurons use
Speaker:a massive amount of energy. So when mitochondria
Speaker:slow down, thinking slows down, memory fades,
Speaker:synapses weakens, inflammation rises. You move
Speaker:more slowly, you move more hesitantly. In
Speaker:Alzheimer's disease, for example, mitochondrial
Speaker:dysfunction shows up early, even before major
Speaker:amyloid buildup. Damaged mitochondria worsen the
Speaker:inflammation in the brain, disrupt neuronal
Speaker:communication and accelerate decline. And even
Speaker:blood tests can show this. Older adults with
Speaker:weaker mitochondrial function often perform worse
Speaker:on memory tests, while stronger mitochondrial
Speaker:performance predicts a, uh, lower dementia risk.
Speaker:Put it simply, healthier mitochondria, healthier
Speaker:brain. So why do we age? We age because our
Speaker:mitochondria age. Now, we've talked in the last
Speaker:two episodes about Nadia. People wanted to top off
Speaker:the nad tank and sounds clever, but it just
Speaker:doesn't reverse aging. And we talked about
Speaker:urolithin A, which is an interesting molecule
Speaker:because it improves endurance a little bit, but it
Speaker:doesn't restore youth. What actively people are
Speaker:looking for is a mitochondrial reset switch, which
Speaker:we don't have yet. We want to have young
Speaker:mitochondria. Well, there are things we can do
Speaker:that actually improves mitochondrial health. Let's
Speaker:start with resistance training. When you lift
Speaker:weights or, uh, push resistance in any form, your
Speaker:mitochondria literally are upgrading themselves.
Speaker:Not only do you make better mitochondria, they
Speaker:remodel. They have a stronger respiratory
Speaker:capacity, they make ATP more efficiently, they're
Speaker:more resilient, they are better with all of those
Speaker:oxidative stress molecules. And that happens in
Speaker:either young people or adult people. And what's
Speaker:more, resistance training for builds new
Speaker:myonuclei, which are control centers that stick
Speaker:around for life and help you adapt faster next
Speaker:time you train. Yes, muscle memory is real, and
Speaker:mitochondria is part of the reason you need
Speaker:examples of resistance training. Dumbbells,
Speaker:resistance band, bodyweight, squats, wall sits,
Speaker:push ups, pilates, kettlebells, chair based
Speaker:resistance for older adults. If you push against
Speaker:force, you're building mitochondria. Now, before
Speaker:anyone asks, no, Vinyasa, yoga is not resistance
Speaker:training. I know it's my favorite exercise. And
Speaker:yes, I've tried to convince myself that holding
Speaker:downward dog for 30 seconds counts as hypertrophy.
Speaker:But my yogi swan does the power yogi interval
Speaker:thing where Suddenly, you're doing planks, lunges,
Speaker:and warrior poses at Mach 3. And by the end, I'm
Speaker:sweating like I'm defending my PhD thesis. So,
Speaker:technically, I get some strengthwear. But let's be
Speaker:honest, if you ever hear me brag about yoga being
Speaker:my resistance training, just pat me on the head
Speaker:and hand the dumbbell a dumbbell. How about Zone
Speaker:two exercise? That's good. So what is Zone two
Speaker:exercise? Now, you can get some wearables, like a
Speaker:whoop or a, uh, Withings, and you can see it. But
Speaker:basically, if you can talk but you can't sing and
Speaker:you're doing some exercise, that's great. For
Speaker:mitochondria, sleep is a mitochondria's
Speaker:powerhouse.
Speaker:That's when mitochondria become repaired. Clean
Speaker:out the old mitochondria. Sleep is your
Speaker:superpower. We're going to have an entire episode
Speaker:about sleep later on. Mediterranean diet. Wow.
Speaker:Yep. Once again, it's protective. It's anti
Speaker:inflammatory. It's proven. Now, there are other
Speaker:things you can do. Here's what makes things worse.
Speaker:High blood sugars, high blood pressure, high ldl,
Speaker:they all destroy mitochondria at a record speed.
Speaker:Take high glucose in patients who have
Speaker:uncontrolled diabetes. Think of them as
Speaker:caramelizing proteins. Think of hypertension or
Speaker:high blood pressure as blasting organs like a fire
Speaker:hose hitting a garden. Think of the high
Speaker:cholesterol that oxidized LDL inflames arteries.
Speaker:Now, we've known about high blood pressure since
Speaker:fdr. Unchecked, high blood pressure destroys
Speaker:longevity. And now we have better medications.
Speaker:Aging is chemistry. It's not mystery. Okay, you're
Speaker:going to hear some influencers insist insulin
Speaker:resistance is the root of everything. And that
Speaker:keto or carnivore solves aging, depression,
Speaker:autoimmune disease, and probably your taxes. Peter
Speaker:Attia and Taubes championed this model years ago.
Speaker:They funded rigorous studies, and the model
Speaker:failed. There's no metabolic advantage to low carb
Speaker:eating. There's no magical fat burning, no insulin
Speaker:trick. And mitochondria actually age a little
Speaker:faster with low carb diets. But the coaches that
Speaker:you'll find on TikTok, uh, Instagram and
Speaker:everywhere else didn't change their program. They
Speaker:just changed their affiliate links. What about
Speaker:alcohol? Alcohol generates oxidative stress that
Speaker:hits mitochondria like a wrecking ball. It damages
Speaker:mitochondrial DNA, disrupts the fission and fusion
Speaker:process of mitochondria, slowing recycling. You
Speaker:know that hangover? It's your mitochondria saying,
Speaker:please don't do that again. Now, this has been
Speaker:kind of a graduate level mitochondria stuff, but
Speaker:you probably figured out that some people use
Speaker:mitochondria and mitochondrial disease the way
Speaker:Deepak Chopra uses the word quantum as some
Speaker:mystical placeholder for whatever they can't
Speaker:explain. It's a God of the gaps thing again. But
Speaker:mitochondria are real. They drive inflammation,
Speaker:metabolism, cancer risk, cognitive function and
Speaker:energy. Understanding them and keeping them
Speaker:healthy helps us age better. Your mitochondria are
Speaker:trying help them out. Research and writing for
Speaker:this episode were done by me, Dr. Terri Simpson.
Speaker:While I'm a board certified physician, I am not
Speaker:your physician. If you're going to change your
Speaker:diet, please see a doctor and a registered
Speaker:dietitian. And for God's sake, if you're
Speaker:undergoing surgery or seeing your doctor, tell
Speaker:them m about every single supplement you take. All
Speaker:things audio come from my friends at Simpler Media
Speaker:and the chief mitochondrion himself, Mr. Evo
Speaker:Terra. As always, Producer Girl Productions turned
Speaker:what started out as a graduate level biochemistry
Speaker:rant into something hopefully you can actually
Speaker:use. Please subscribe and rate the show and follow
Speaker:me on Substack, where you'll find the full
Speaker:breakdown and references and your doctor's orders
Speaker:and4q.com whichever one you like. Have a great
Speaker:week. Take care of your mitochondria. They're
Speaker:working hard even when you're resting. Hey, Evo,
Speaker:how are your mitochondria doing? Well, after this
Speaker:episode, I've got a whole new plan. Sleep more and
Speaker:get my mitochondria to quit drinking. Right. Okay,
Speaker:let's go with that.
