YT YouTube2Text

YouTube2Text → Transcripts → How to Build "Superager" Mitochondria (3 Steps)

How to Build "Superager" Mitochondria (3 Steps) — Transcript

by Nick Norwitz MD PhD · 3,597 words · 630 segments · language en · Watch on YouTube

Open in transcriber Summarize with AI Download SRT/VTT

Full transcript

0:00If you look for the biological
0:01signatures that distinguish the
0:03longest-lived humans, the super agers,
0:05including a report of a woman who lived
0:07to 117, what stands out in healthy aging
0:10is healthy mitochondria. But, the
0:12amazing thing about mitochondria is
0:14that, unlike a battery or a car engine,
0:16mitochondria can heal, recover, and
0:19renew themselves. And you can make them
0:21do this starting today with free tools
0:24and also cutting-edge
0:25performance-enhancing mitochondrial
0:27peptides and hormones, which [music]
0:29raises the
0:31question: Why do people lose energy as
0:32they age, and is that decline
0:34reversible? In fact, little spoiler,
0:37when I used one of these tools for a
0:38week, I felt supercharged. It was
0:40insane, and I got to tell you about it.
0:42But, at a high level, today we're going
0:45to unpack the tools, the fundamental
0:47tools to help you reset and upgrade your
0:49mitochondria to accomplish better health
0:51at a fundamental level, better energy,
0:53better aging, all of it. We're going to
0:55start with the most accessible and free
0:56tools and then progress to something
0:59that's more experimental.
1:02Let's go. Obesity, processed foods,
1:04circadian disruption, environmental
1:06pollutants, and physical inactivity are
1:08the root cause of autoimmune and
1:10inflammatory diseases. So, when it comes
1:11to long-term mitochondrial health and
1:13your overall health, the fundamentals
1:15are critical.
1:16>> Crohn's disease is when your immune
1:18system attacks itself.
1:19>> They effectively become more powerful
1:21and efficient. Their metabolic rate in
1:23their fat tissue was more than twice
1:25>> There's a lot of mitochondria.
1:29>> Now, real quick, before we begin, some
1:31of you may have noticed I'm trying a new
1:32format where I consolidate a series of
1:35Stay Curious Metabolism letters covering
1:37dozens of papers into a single coherent
1:39story. And today, that story is all
1:41about upgrading your mitochondria,
1:43rebooting and upgrading your body's
1:45batteries. That said, if you really want
1:48to dive into the fundamentals and
1:50primary literature, I do encourage you
1:51to check out our Stay Curious Metabolism
1:53community. It is quickly become one of
1:55the best-selling science newsletters on
1:57Substack in the world. And I'm proud to
2:00say subscribers call it the best
2:01investment they've made in their health.
2:03For an example, one subscriber Victor
2:05said, "I can't believe you provide
2:0740,000 words of graduate level education
2:09for less than the cost of one run to
2:11Starbucks per month."
2:13Am I blushing?
2:14Anyway, if you want to go even deeper
2:16with me and gain insights you won't gain
2:18elsewhere on all things metabolic
2:20health, please check it out after
2:22watching this video. But, with that
2:23said, let's build our road map like
2:25mitochondria builds ATP. In part one,
2:28we're going to talk about free and
2:29foundational tools for your
2:30mitochondria. Things you can do outdoors
2:32in the morning, in your kitchen, in your
2:34daily routine. Then we'll move to the
2:35more advanced tier, part two,
2:37mitochondrial peptides. One that is FDA
2:40approved for mitochondrial disease and
2:43another remarkable mitochondrial derived
2:46hormone. And then finally, in part
2:48three, we're going to get a glimpse of
2:49the future of mitochondrial health. So,
2:52let's begin. Part one, free and
2:54foundational tools. Let's start at the
2:56beginning of your day, when you wake up
2:58to greet the sun.
2:59>> [screaming]
3:01>> Unless of course you live in Boston in
3:02the winter and spend several months of
3:03the year like a vitamin D starved golem.
3:07Jokes aside, exposure to morning
3:09sunlight does something interesting.
3:12It kicks off a mitochondrial dance. What
3:15do I mean by this? Well, your
3:16mitochondria aren't fixed static little
3:19batteries. They ebb and flow. They
3:21literally fuse together then break apart
3:23in a dynamic process known as fusion and
3:26fission. And this mitochondrial dance of
3:28fusion and fission is critically
3:30important for maintaining mitochondrial
3:32function. When mitochondria fuse
3:33together, they effectively become more
3:36powerful and efficient. But, breaking
3:38apart, the fission part, matters too. It
3:40helps us segregate out old damaged
3:43mitochondrial components so they can
3:44broken down and recycled in a process
3:46known as mitophagy. Or to simplify and
3:48by way of analogy, imagine if the
3:50batteries in your phone merge together
3:53in a super battery when demand increased
3:55and then split apart to repair
3:57themselves. That's basically what's
3:59happening in your body with your
4:00mitochondria trillions and trillions of
4:03times per day. Yeah, trillions with a T.
4:06There are a lot of mitochondria. Anyway,
4:08this balance between fusion and fission,
4:09building up and breaking down is
4:11dictated by light and circadian rhythm.
4:14In fact, there was a fascinating paper
4:16out of Oxford last year coincidentally
4:18published in the exact same department
4:20where I did my PhD, the Department of
4:21Physiology, Anatomy and Genetics.
4:23Anyway, it identified the dance of
4:25mitochondrial fusion and fission as one
4:27of the key drivers of sleep. Now, there
4:31are some experiments you just can't do
4:33in humans for ethical or practical
4:35reasons. Like you can't gene edit a full
4:36human to make mitochondria dance
4:38differently. But when researchers
4:39manipulate mitochondrial fusion and
4:41fission in animals, they can actually
4:43alter sleep drive and desire to sleep.
4:46And it's a bidirectional dance. Light
4:49regulates mitochondrial dynamics,
4:51mitochondrial dancing, and mitochondrial
4:52dynamics regulate sleep. So, stepping
4:55back, if light helps regulate
4:58mitochondrial dynamics and mitochondrial
4:59dynamics ultimately dictate the
5:01long-term function of basically every
5:03organ in your body,
5:05we return to that question. What's the
5:07actionable insight? Well, here it is. As
5:09best you can, get exposure to morning
5:11sunlight or if that's not feasible, get
5:13a 10,000 lux lamp. It's like 40 bucks on
5:15Amazon. 40 bucks on Amazon. And
5:17>> What a time
5:19for mine to break. Like literally right
5:21now.
5:21>> And minimize exposure to bright
5:23artificial light at night. As basic as
5:25this sounds, basically what it does is
5:27it helps initiate and synchronize the
5:29mitochondrial dance, your mitochondrial
5:31fusion and fission dynamics as part of
5:33an evolutionarily appropriate circadian
5:35rhythm. And in doing so, it likely helps
5:37preserve mitochondrial function and
5:38health over the long term, over years,
5:41over decades, across your whole body.
5:43So, basically, getting morning sunlight
5:45and minimizing exposure to artificial
5:47light at night is like getting an
5:48orchestra conductor to lead a harmonious
5:51symphony. So, when the sun comes up, say
5:54hi.
5:55>> Stay curious [singing]
5:57side
5:59quest.
6:00>> But now I do need to take you on a
6:01little stay curious side quest because
6:03there's a fascinating hypothesis about
6:05mitochondria. Specifically, leaky
6:08mitochondria as a root cause of
6:10autoimmune and inflammatory diseases. A
6:12paper published in nature proposes
6:14something remarkable. The many
6:16autoimmune and inflammatory diseases
6:18stem from a breakdown of the ancient
6:20relationship between your body and your
6:22mitochondria. Now, to understand this,
6:25you need to remember that mitochondria
6:27were once free-living bacteria-like
6:29organisms that fused with our cells
6:31roughly 2 billion years ago in a process
6:34known as endosymbiosis.
6:36Endo meaning within or inside, sin
6:38meaning together, and biosis meaning
6:40living. Endosymbiosis.
6:42Basically, your mitochondria are like
6:44ancient bacterial refugees that struck a
6:47peace treaty with your cells billions of
6:48years ago.
6:51But consider that because of their
6:53foreign origins, mitochondria still
6:55retain bacteria-like signatures that our
6:58human immune systems can recognize as
7:00the other or invader.
7:02>> What are you doing in my swamp?
7:08>> Now, normally mitochondria are kept
7:09safely within the cell. But under
7:11conditions of stress and dysfunction,
7:14mitochondria contents can leak out and
7:16trigger inflammatory immune signaling.
7:19And the researchers argue that this
7:21break in endosymbiosis, or leaky
7:23mitochondria, may be one of the root
7:25causes of inflammatory and autoimmune
7:26diseases. Things like inflammatory bowel
7:28disease.
7:29>> Yeah, when I was 15, I just started
7:31going to the bathroom 8, 9, 10 times a
7:32day, not digesting any foods.
7:35>> Lupus, rheumatoid arthritis, multiple
7:36sclerosis.
7:38In other words, autoimmune diseases may
7:40represent a breakdown in the diplomatic
7:42relations between our cells and their
7:45ancient bacterial energy partners,
7:47mitochondria.
7:48And really importantly,
7:50what seems to drive leaky mitochondria
7:53in the first place?
7:55Features of modern living. Obesity,
7:56processed food
7:57>> I'm making waffles.
7:58>> circadian disruption, environmental
8:00pollutants, and physical inactivity. So,
8:03am I saying that routine trips to
8:04McDonald's can break open your
8:06mitochondria causing spillage that
8:07triggers chronic disease?
8:09Well, I'm not not saying that.
8:12>> Stay curious [singing]
8:15side quest.
8:16>> Now, I want to get back to our main
8:18narrative, but before I get to the more
8:19advanced topics, I want to emphasize
8:21that when it comes to long-term
8:23mitochondrial health and your overall
8:25health, the fundamentals are critical.
8:27Sleep, exercise, avoiding environmental
8:29pollutants as best as you can, eating a
8:30minimally processed diet. If you aren't
8:33doing those things, then finagling at
8:34the margins like we're about to do is
8:37kind of like adding a multivitamin gummy
8:39onto a fast food diet. That said, if
8:41your foundations are nearly optimized,
8:44there may be ways to further top off
8:46your mitochondrial function, upgrade
8:48your mitochondria. And one particularly
8:50interesting approach is a ketogenic
8:52diet. Now, you've probably heard of
8:54ketogenic diets in the context of weight
8:56loss, blood sugar control, or generating
8:58ketone bodies to fuel the brain, but
9:00their effects appear to extend further
9:02and much deeper into the foundation of
9:03our energy metabolism, affecting our
9:05mitochondria. After all, if you cut
9:08carbs and shift your entire body's
9:09metabolism from running on carbs to
9:11running on fat, maybe it's unsurprising
9:13that the organelles responsible for
9:15generating energy from fat,
9:17mitochondria, change as well.
9:19Specifically, when animals are fed a
9:21ketogenic diet, their mitochondria
9:23appear to become physically larger, more
9:25numerous, and more powerful. You can see
9:28that here. This is an electron
9:30microscopy image, and the M is visible
9:32enlargement of the mitochondria on a
9:34ketogenic diet. You can also take a look
9:36at the L. These are lipid droplets.
9:39Unlike the mitochondria, which became
9:40bigger, the lipid droplets become
9:41smaller, more numerous, effectively
9:44increasing surface area and improving
9:45the tissue's ability to burn fat for
9:47energy. So, in other words, ketogenic
9:50diets literally remodel fat tissue
9:53towards enhanced fat burning. Bigger
9:55mitochondria and smaller, more numerous
9:57lipid droplets. And if you think about
9:59it, this makes perfect sense. If carbs
10:01become scarce, your body needs to
10:02upgrade the machinery required to run
10:04fat, including mitochondria.
10:06Now, I did say animal data. Do we see
10:09any signals in the human data?
10:11We do. In human controlled feeding
10:13studies, when carb calories are
10:15progressively swapped for fat calories
10:18while trying to maintain weight, energy
10:20expenditure in humans increases on the
10:22lower carb diets.
10:24And when researchers take muscle
10:26biopsies from these humans in these
10:29studies,
10:30what do they find?
10:31Increased mitochondrial power. In other
10:34words, exactly the sort of mitochondrial
10:36adaptations we'd expect.
10:38>> But [snorts] don't just take my word for
10:39that. I actually reached out to the lead
10:41author of this research, Professor Ben
10:42Bickman, a respected academic, name you
10:44guys know, and a friend of mine. Here's
10:46what he had to say.
10:47>> What we [snorts] found is that when
10:49ketones are elevated, fat cells are
10:51burning faster. Or in other words, their
10:54metabolic rate went up. In fact, we
10:56confirmed this in all three commonly
10:58used biomedical models. In fat cells
11:01grown in a petri dish, in adipose tissue
11:03from rodents, and even adipose tissue
11:05from humans, where we took little fat
11:08biopsies from the belly. In fact, in the
11:11humans, when they were in ketosis, their
11:13metabolic rate in their fat tissue was
11:16more than twice it of what it was when
11:19their ketones were not elevated.
11:21>> So, now a bigger picture starts to
11:22emerge. At the microscopic level,
11:24ketogenic diets and lower carb diets
11:27remodel mitochondrial structure and
11:28function, and at the whole body level,
11:31humans exhibit increases in
11:32mitochondrial capacity and energy
11:33expenditure when on ketogenic diets.
11:36Okay, I swore last tangent then we're
11:37going to get on to the more advanced
11:38tools, but I do need to tell you about a
11:40foundational tool and a new paper that
11:41came out yesterday as I record this that
11:43blew my mind. It was published in Nature
11:46Aging July 3rd, 2026. And what they did
11:50was they took muscle biopsies from
11:52humans, young adults and older adults
11:54split across the fitness and training
11:58spectrum. So, trained, normal, and then
12:01physically impaired. They asked the
12:02question, "What changes in human muscles
12:05in terms of gene expression as we age
12:08and what doesn't if adults are trained
12:10and fit?" And the punchline is in
12:13trained fit older adults, 55%
12:18of the gene expression changes we
12:19associate with age
12:21didn't happen. They were absent and
12:23those 55% were enriched in mitochondrial
12:26and energy metabolism pathways. So, the
12:28punchline is those changes we think
12:30happen in muscle with age to slow your
12:33metabolism, decreases in mitochondrial
12:35complex one and four for example, they
12:37don't happen if you stay
12:39trained, fit, and exercise. So, really
12:43what I'm saying here is that exercise
12:46isn't just building a muscular reserve,
12:47it changes the operating system of your
12:49mitochondria to preserve youth as you
12:51age. How amazing is that? But more
12:53information below, but now as I promised
12:55we're going to get to the more advanced
12:56topics. But now let's move to something
12:57more cutting edge. What happens when we
13:00target mitochondria directly? This
13:02brings us to part two, mitochondrial
13:04peptides. Let's take things a step
13:06further and talk about peptides starting
13:08with one called SS-31 which stands for
13:11super soldier 31.
13:13Not really, I totally made that up. But
13:15wouldn't that be cool? Anyway, to
13:16understand why SS-31 matters, you need
13:20to understand a bit more about
13:21mitochondrial biology. So, hang on with
13:23me while we dive into the mitochondria,
13:25literally. Inside mitochondria is a
13:27highly folded inner membrane where
13:29energy production actually occurs. It's
13:32like packing an entire power plant into
13:34microscopic origami folds. And embedded
13:37within that inner mitochondrial membrane
13:39are the complexes of the electron
13:41transport chain, the literal machinery
13:43that generates ATP energy keeping you
13:45alive.
13:47Now, let's double-click on those inner
13:48membrane folds. These are critical. They
13:51do two things. One, they increase
13:53surface area for energy production. But
13:55maybe more importantly, they organize
13:57how the machinery in mitochondria
13:59interacts with one another. By way of
14:01analogy, and sorry to mix analogies,
14:03it's like if you're cooking a dish, you
14:04want all the ingredients and tools in
14:06one place, what the French call mise en
14:09place, rather than running around to
14:10grab ingredients and tools as you're
14:11cooking. This is much more efficient.
14:14And this is kind of how mitochondria
14:15work. The inner membrane organizes the
14:17complexes needed to generate energy.
14:19Okay. Now, enter something called
14:21cardiolipin. Cardiolipin maintains the
14:24structure of this inner membrane and
14:26thereby provides essential support for
14:28mitochondrial energy production. Or to
14:30extend the origami analogy from earlier,
14:32cardiolipin acts like adding glue to
14:34your origami power plant. It literally
14:36holds the structures together, at least
14:38when you're healthy. But when
14:40cardiolipin isn't doing its job to
14:42support mitochondria, energy metabolism
14:44begins to fall apart at the most
14:46fundamental level. There are, in fact,
14:48human defects in cardiolipin that
14:50manifest in the condition known as Barth
14:52syndrome with muscle weakness, heart
14:54problems, and extreme fatigue. More on
14:57Barth syndrome in a moment. Anyway, as
14:59mitochondria become damaged with aging
15:01and disease, cardiolipin becomes
15:03destabilized, which means mitochondrial
15:05structure literally deteriorates and
15:07energy production starts to fail. This
15:09is where our peptide friend, SS-31,
15:12finally comes in to rescue the day.
15:14>> Don't you say
15:14>> I know I LEFT.
15:15>> COME ON.
15:16>> SS-31 is a mitochondrial targeting
15:18peptide that homes to the inner
15:21mitochondrial membrane like a smart
15:23heat-seeking missile, binds to
15:24cardiolipin itself and helps stabilize
15:27the machinery responsible for energy
15:29production in your mitochondria. So, if
15:31cardiolipin is like Elmer's Glue, the
15:33SS-31 turns it into superglue. And this
15:36isn't just fringe biohacker speculation.
15:39SS-31 was FDA-approved for Barth
15:41syndrome, a devastating rare
15:43mitochondrial condition characterized by
15:45cardiolipin dysfunction. Wow, we
15:46deployed that knowledge on Barth
15:47syndrome pretty fast. Now, in a
15:49randomized placebo-controlled human
15:51trial, SS-31 improved fatigue and
15:54physical performance in these patients.
15:56But, I know what you're thinking.
15:58I don't have Barth syndrome. You don't
15:59have Barth syndrome. Almost none of you
16:00have Barth syndrome.
16:01But, mitochondrial dysfunction is not
16:03unique to rare diseases. It's a hallmark
16:05of aging itself, along with chronic
16:07diseases like heart disease, diabetes,
16:09neurodegeneration, and metabolic
16:10dysfunction more broadly.
16:13That is why researchers are now
16:15exploring SS-31 in the context of heart
16:18disease, Alzheimer's disease, diabetes,
16:20and so on. The preclinical literature on
16:22SS-31 is really promising. SS-31 has
16:25been shown to preserve mitochondrial
16:26structure, reduce scarring of the heart
16:29after injury, restore mitochondrial
16:31integrity in diabetic retinas, and even
16:33improve cognitive function in animal
16:35models of Alzheimer's disease.
16:37Which is freaking cool.
16:39Now, to be clear, this does not mean
16:41SS-31 is some proven anti-aging peptide
16:44miracle. Human efficacy data remains
16:46limited outside this rare mitochondrial
16:48disease we talked about. But, if you
16:50want a glimpse into the future of
16:51mitochondrial medicine, it might be
16:53worth watching this molecule.
16:55With that, let's pivot and talk about
16:57another mitochondrial peptide that's
16:58becoming increasingly popular and better
17:00known than SS-31. It's called MOTS-c.
17:04Now, MOTS-c is a peptide, but I like to
17:06call it a mitochondrial hormone because
17:08it's that as well. MOTS-c is actually
17:10encoded by the mitochondrial DNA itself.
17:13That's right. Mitochondria don't just
17:15generate energy. They also have their
17:17own miniature genomes, which is a
17:18remnant of their ancient bacteria-like
17:20origins. And this mitochondrial DNA is
17:23capable of producing signaling molecules
17:24called myokines, which literally means
17:27mitochondrial hormones, including
17:29MOTS-c. Now, one thing that makes MOTS-c
17:31interesting to me is that it's naturally
17:33stimulated in humans by exercise. In
17:36human studies, exercise increases MOTS-c
17:39levels nearly 12-fold within muscle.
17:41MOTS-c kind of functions like an
17:43internal exercise memo sent from
17:45mitochondria to the rest of the body.
17:47So, that begs the question, what if you
17:48just give the MOTS-c exercise memo even
17:51without exercise? Well, animals treated
17:54with MOTS-c demonstrated dramatic
17:56improvements in endurance and power. In
17:59one experiment, 16.6% of control animals
18:02could complete the highest treadmill
18:04speed on a running test. But when they
18:06were given MOTS-c,
18:07100%, every single animal could beat the
18:11test, completely obliterate the test.
18:16And it wasn't just exercise performance.
18:18MOTS-c also reduced fat gain while
18:20preserving lean mass. At a very high
18:22level, you can think of MOTS-c as a
18:24mitochondrial signal telling the
18:26organism, the whole organism, to adapt,
18:28become stronger, faster, better.
18:32With that, I do want to emphasize MOTS-c
18:35is experimental. And this is very much a
18:37don't necessarily do what I do sort of
18:39situation. That said, I did have to
18:42experiment with it myself. I ran a short
18:45week-long cycle, over which I wouldn't
18:47expect major changes in body
18:48composition.
18:50But I absolutely noticed my exercise
18:52performance increased, particularly with
18:54endurance. For example, during my
18:56high-intensity interval sessions, my
18:57times improved and my fatigue
18:59diminished. In general, workouts just
19:01felt more easier and more pleasurable. I
19:04also noticed a strong spontaneous drive
19:06to move throughout the day, even more
19:08than normal, which ultimately showed up
19:10in activity metrics. Since I started
19:12this mod C a few days ago, I just had
19:13this incredible compulsion to move like
19:1518, 20, 22,000 steps per day
19:17spontaneously. I've actually been taking
19:19a lot of my calls outside cuz I just
19:21don't want to sit down, which also means
19:23I'm getting more sunlight, which makes a
19:24nice little self-reinforcing
19:26mitochondrial health loop. How about
19:28that? And my experience lined up
19:30remarkably well with both the animal
19:31literature and a growing body of
19:33anecdotal reports emerging from the
19:35biohacker community. To share just a few
19:37comments I received from friends after I
19:39did my experiment. People say things
19:41like, "It feels like an amplifier for my
19:43morning workout." Or, "It's like having
19:45an extra gear I didn't know I could
19:46access." Or, "My afternoon fatigue just
19:50vanished. Poof."
19:51Those are the kind of comments people
19:53are reporting when taking mod C. So, if
19:56SS-31 is about stabilizing the structure
19:58and machinery of mitochondria, mod C
20:00appears to be more about metabolic
20:02signaling, adaptation, and resilience.
20:04And together they offer a fascinating
20:06glimpse into what the future of
20:07mitochondrial medicine might look like.
20:10But that brings us to this future, part
20:12three, the future of mitochondrial
20:14health. Because peptides like SS-31 and
20:16mod C may just be the beginning. In
20:19fact, we're already seeing early work on
20:21something that seems fantastical,
20:23ambitious.
20:25Mitochondrial transplantations.
20:30While this sounds like science fiction,
20:32there are already compelling animal data
20:34and even early-stage human trials
20:36beginning to emerge. For example, a
20:38recent 2026 study published in Cell
20:41explored transplanting mitochondria
20:43wrapped in red blood cell membranes into
20:45animals to rescue mitochondrial
20:47dysfunction. And in a mouse model of
20:49Parkinson's disease, which is typified
20:51by mitochondrial dysfunction, these
20:52mitochondrial transplants reduced neuron
20:55loss, improved motor function, and
20:58restored mitochondrial activity within
21:00the affected brain regions.
21:02This isn't just incremental progress.
21:04[music] It's a leap forward in
21:06regenerative medicine. I'm getting
21:07goosebumps just talking about it.
21:09Seriously, imagine not far from now
21:11having a literal mitochondrial
21:13bioreactor [music] in your kitchen,
21:15maybe next to your coffee machine,
21:17generating fresh, highly functional
21:19mitochondria that can be infused [music]
21:20back into the body periodically, maybe
21:22paired with compounds like SS-31 to heal
21:25and preserve the integrity of
21:26mitochondria.
21:27>> [music]
21:27>> I know that sounds futuristic, but
21:29here's what I need to tell you. That
21:31future is closer
21:32than most people think.

About this transcript

This page contains the full transcript of How to Build "Superager" Mitochondria (3 Steps) by Nick Norwitz MD PhD, generated from the public captions YouTube serves with the video. The transcript has 3,597 words across 630 segments, with the original timestamps preserved so you can click any line to jump to that moment in the embedded player.

What you can do with it

Use the transcript to take notes, quote the speaker, build a study guide, generate a summary with ChatGPT or Claude via the YouTube Summary tool, or export it as a timed subtitle file with YouTube to SRT. You can also re-open it in the transcriber to choose a caption track available on the video.

Free YouTube transcript tool

YouTube2Text is a free YouTube transcript generator — no signup, no daily limit. Paste any YouTube link and get the full transcript instantly, with timestamps, click-to-jump, caption language selection, AI prompts for ChatGPT, Claude, and Gemini, and exports to TXT, SRT, VTT, or Markdown.