# Upstream Longevity

> Longevity and biohacking, traced to the root cause and explained simply. Every claim cites its sources and is graded by strength of evidence.

Upstream Longevity is an independent editorial project, not written by doctors. Each article starts from a symptom people feel (fatigue, brain fog, weight, joints) and keeps asking "what comes before this?" until it reaches a cause at the level of the cell, then reviews what acts on that cause. Evidence grades: A = human randomized trials, B = human observational studies, C = animal studies, D = mechanism only. Every technical term is defined in plain language and linked to the glossary. Content is educational, not medical advice.

## Energy & Mitochondria

Why energy fades with age, traced down to the power plants inside your cells.

- [Energy & Mitochondria - all articles](https://upstreamlongevity.com/energy)
- [Why am I always tired after 40? The upstream answer](https://upstreamlongevity.com/energy/always-tired-after-40): Always tired after 40? First rule out the usual medical suspects. Then trace fatigue upstream to your cells, and see what actually brings energy back.
- [How to increase mitochondria naturally (and what's just hype)](https://upstreamlongevity.com/energy/how-to-increase-mitochondria): You can build new mitochondria at any age. What actually triggers it, why volume and intensity do different jobs, and which popular methods do little.
- [Does urolithin A work? What the human trials actually show](https://upstreamlongevity.com/energy/does-urolithin-a-work): Urolithin A promises to recycle worn-out mitochondria. We read every human trial: what improved, what didn't, who paid for them, and who might benefit.
- [The first part of you to break isn't in your nucleus](https://upstreamlongevity.com/energy/mitochondrial-dna-aging): Mitochondrial DNA mutates faster than nuclear DNA, but probably not because of free radicals. What the sequencing data shows and what actually acts on it.
- [CoQ10: who actually needs it?](https://upstreamlongevity.com/energy/coq10-who-needs-it): CoQ10 is one of the most popular supplements after 40. Who has a real reason to take it, what statins do to it, and where the evidence is weak.
- [NMN vs NR vs NAD⁺: what actually raises NAD⁺, and does it matter?](https://upstreamlongevity.com/energy/nmn-vs-nr-vs-nad): NMN, NR, NAD+ pills and IV drips all promise more NAD+. What each one actually raises in humans, what it changes, and what it doesn't. Evidence graded.
- [Zone 2 training for longevity: how to do it, and what the hype gets wrong](https://upstreamlongevity.com/energy/zone-2-training-longevity): Zone 2 training is everywhere. How to find your zone 2, why it helps, and what 2025 research says about the claim that it beats harder exercise.
- [Brain fog after 40: what comes before it](https://upstreamlongevity.com/energy/brain-fog-after-40): Brain fog after 40 is common but rarely random. The medical causes to rule out, what the brain needs to think clearly, and what actually clears the fog.

## Fasting & Metabolism

What really happens inside you when you don't eat, and what that means for aging.

- [Fasting & Metabolism - all articles](https://upstreamlongevity.com/fasting)
- [How long do you have to fast for autophagy? The honest answer](https://upstreamlongevity.com/fasting/how-long-to-fast-for-autophagy): The "16 hours for autophagy" rule is everywhere. Where it came from, what mouse and human studies actually show, and what we really know about fasting and cell cleanup.
- [Does coffee break a fast? It depends what you're fasting for](https://upstreamlongevity.com/fasting/does-coffee-break-a-fast): Black coffee, cream, sugar, collagen, MCT oil: what breaks a fast and what doesn't, depending on whether you fast for weight, blood sugar, autophagy or gut rest.
- [Early signs of insulin resistance, and what comes before them](https://upstreamlongevity.com/fasting/insulin-resistance-early-signs): Insulin resistance starts years before blood sugar rises. The early signs, the tests that catch it, what drives it upstream, and what reverses it.
- [The fasting mimicking diet: does it work?](https://upstreamlongevity.com/fasting/fasting-mimicking-diet): The fasting mimicking diet promises fasting benefits while still eating. What the human trials found on weight, blood pressure, IGF-1 and "biological age", and the caveats.
- [mTOR and aging: the growth switch you want on, and off](https://upstreamlongevity.com/fasting/mtor-and-aging): mTOR is the cell's master growth switch, and turning it down extends life in animals. Why you can't just shut it off, what rapamycin showed, and how to balance it.
- [Berberine vs metformin: what the evidence actually says](https://upstreamlongevity.com/fasting/berberine-vs-metformin): Berberine is called "nature's Ozempic" and "nature's metformin". How it really compares on blood sugar, weight and longevity, plus a surprise about metformin and exercise.
- [Does intermittent fasting slow aging? What the trials say](https://upstreamlongevity.com/fasting/intermittent-fasting-aging): Intermittent fasting is sold as an anti-aging hack. What human trials actually show about fasting, calorie restriction and the pace of aging.

## Supplements Decoded

What each supplement actually does in the body, and how strong the evidence really is.

- [Supplements Decoded - all articles](https://upstreamlongevity.com/supplements)
- [The best supplements for longevity, graded by evidence](https://upstreamlongevity.com/supplements/best-supplements-for-longevity): Creatine, omega-3, vitamin D, magnesium, NMN, taurine and more: an honest A-to-D evidence grade for every popular longevity supplement, including the ones that may harm.
- [Spermidine: autophagy from your plate?](https://upstreamlongevity.com/supplements/spermidine-benefits): Spermidine switches on cellular recycling and extended life in mice. What human studies show, the best food sources, and why a 12-month trial didn't improve memory.
- [Taurine and aging: the breakthrough, and the plot twist](https://upstreamlongevity.com/supplements/taurine-and-aging): A 2023 Science study said taurine extended life in mice and falls with age in humans. A 2025 study challenged it. What we know about taurine supplements now.
- [Creatine for the brain and aging, not just muscles](https://upstreamlongevity.com/supplements/creatine-brain-aging): Creatine is famous for muscle, but it also fuels the brain. What the evidence shows for strength after 50, memory and sleep deprivation, plus dose and safety.
- [Which type of magnesium for what?](https://upstreamlongevity.com/supplements/which-magnesium): Glycinate, citrate, oxide, threonate, malate: what each form of magnesium is actually good for, which absorb best, what the sleep evidence shows, and who should be careful.
- [Resveratrol: what happened to the red wine miracle?](https://upstreamlongevity.com/supplements/resveratrol-does-it-work): Resveratrol was the red wine molecule that would slow aging. A $720 million deal later, here's what the human evidence shows, and the lessons for every longevity supplement.
- [Omega-3 and aging: what the newest data actually shows](https://upstreamlongevity.com/supplements/omega-3-and-aging): Fish oil failed to prevent heart attacks in healthy people in a huge trial, yet a 2025 study found it slowed biological aging. How both can be true, and who benefits.
- [Vitamin D and K2 together: why it matters, and what's hype](https://upstreamlongevity.com/supplements/vitamin-d-and-k2): Vitamin D failed to prevent cancer and heart disease in a huge trial but cut autoimmune disease. What vitamin K2 adds, the newest calcification trial, and who should test first.

## Ancient Wisdom, Tested

What Ayurveda and other ancient systems got right about long life, and what science says now.

- [Ancient Wisdom, Tested - all articles](https://upstreamlongevity.com/ancient-wisdom)
- [Ayurveda and longevity: what science says about the ancient system](https://upstreamlongevity.com/ancient-wisdom/ayurveda-longevity): Ayurveda built a whole branch of medicine around long life. What it got right by modern standards, what doesn't hold up, and the real risks, from heavy metals to liver injury.
- [Triphala: the three-fruit formula, tested](https://upstreamlongevity.com/ancient-wisdom/triphala-benefits): Triphala is Ayurveda's famous three-fruit formula for digestion and renewal. What studies show for constipation, gums and gut health, and where evidence is missing.
- [Shilajit: benefits, claims and heavy-metal risk](https://upstreamlongevity.com/ancient-wisdom/shilajit-benefits-risks): Shilajit, the black mountain resin, is trending for energy and testosterone. What little human research exists, the fulvic acid claims, and why contamination is the biggest concern.
- [Ashwagandha: benefits, risks and who should avoid it](https://upstreamlongevity.com/ancient-wisdom/ashwagandha-benefits-risks): Ashwagandha has real trial evidence for stress and sleep. It's also been linked to liver injury and banned in Denmark. What the evidence says, and who should skip it.
- [Oil pulling: does it actually work?](https://upstreamlongevity.com/ancient-wisdom/oil-pulling): Swishing coconut or sesame oil is an old Ayurvedic habit and a modern trend. What trials show for plaque, gums and bad breath, what it can't do, and how it compares to mouthwash.
- [Nasal rinsing (jala neti): benefits and the one safety rule](https://upstreamlongevity.com/ancient-wisdom/nasal-rinse-safety): Ayurveda's jala neti is now recommended for chronic sinus problems. What the evidence shows, how to rinse properly, and the water rule that prevents rare but deadly infections.
- [Turmeric and curcumin: why absorption is the whole story](https://upstreamlongevity.com/ancient-wisdom/turmeric-curcumin-absorption): Curcumin barely gets into your blood. What the famous "2000% with black pepper" figure is really based on, what helps joint pain, and the liver injury cases nobody mentions.

## Glossary

Plain-language definitions of longevity and biology terms, each with an everyday analogy, why it matters for aging and a common myth.

- [Glossary index](https://upstreamlongevity.com/glossary)
- [Adaptogen](https://upstreamlongevity.com/glossary/adaptogen): An adaptogen is an herb or compound claimed to help the body adapt to stress and restore balance, such as ashwagandha, rhodiola or ginseng.
- [Amino acids](https://upstreamlongevity.com/glossary/amino-acids): Amino acids are the small building blocks that link together in chains to form proteins, the molecular machines and structures of your body.
- [AMPK](https://upstreamlongevity.com/glossary/ampk): AMPK is a protein that works as your cells' fuel gauge: when energy runs low, it switches on and tells the cell to burn fuel, save energy and recycle old parts.
- [Antioxidants](https://upstreamlongevity.com/glossary/antioxidants): Antioxidants are compounds that neutralize free radicals, the unstable molecules that can damage cells.
- [Ashwagandha](https://upstreamlongevity.com/glossary/ashwagandha): Ashwagandha is a shrub whose root is used in Ayurveda to help the body handle stress, and in modern trials it modestly reduced stress, cortisol and sleep problems.
- [ATP](https://upstreamlongevity.com/glossary/atp): ATP is the tiny molecule every cell uses as its energy currency: it carries energy to wherever work needs to be done, from a muscle contracting to a thought firing.
- [Autophagy](https://upstreamlongevity.com/glossary/autophagy): Autophagy is the recycling system inside your cells: it collects worn-out and broken parts, breaks them down and reuses the materials.
- [Ayurveda](https://upstreamlongevity.com/glossary/ayurveda): Ayurveda is India's traditional system of medicine, developed over more than two thousand years, that aims to keep body, mind and environment in balance through diet, daily routine, herbs and cleansing practices.
- [BDNF](https://upstreamlongevity.com/glossary/bdnf): BDNF is a protein your brain makes that helps nerve cells survive, grow and build new connections, which is the physical basis of learning and memory.
- [Berberine](https://upstreamlongevity.com/glossary/berberine): Berberine is a yellow compound from plants such as goldenseal and barberry that modestly lowers blood sugar, partly by switching on the cell's fuel gauge, AMPK.
- [Bioavailability](https://upstreamlongevity.com/glossary/bioavailability): Bioavailability is how much of something you swallow actually gets absorbed and reaches your bloodstream in a usable form.
- [Brown fat](https://upstreamlongevity.com/glossary/brown-fat): Brown fat is a special type of body fat packed with mitochondria that burns energy to produce heat instead of storing it.
- [Calorie restriction](https://upstreamlongevity.com/glossary/calorie-restriction): Calorie restriction means eating noticeably fewer calories than usual, often 10 to 30 percent less, while still getting all the nutrients you need.
- [CoQ10](https://upstreamlongevity.com/glossary/coq10): CoQ10 is a molecule inside your mitochondria that helps pass energy along the assembly line that recharges ATP, and it also works as an antioxidant.
- [Cortisol](https://upstreamlongevity.com/glossary/cortisol): Cortisol is the body's main stress hormone, a chemical messenger released by the adrenal glands that mobilizes energy and prepares you to handle a challenge.
- [Creatine](https://upstreamlongevity.com/glossary/creatine): Creatine is a natural compound that muscles and the brain use as a fast backup energy supply, instantly recharging ATP, the molecule cells run on.
- [Curcumin](https://upstreamlongevity.com/glossary/curcumin): Curcumin is the main active compound in turmeric, a yellow spice used in Ayurveda, studied for anti-inflammatory effects but very poorly absorbed by the body.
- [DNA](https://upstreamlongevity.com/glossary/dna): DNA is a very long molecule inside your cells that stores the instructions for building and running your body, written in a code of just four chemical "letters".
- [Dysbiosis](https://upstreamlongevity.com/glossary/dysbiosis): Dysbiosis is an imbalance in the community of microbes living in your body, for example in your gut or mouth, where helpful species decline and harmful ones gain ground.
- [Enzyme](https://upstreamlongevity.com/glossary/enzyme): An enzyme is a protein that makes one specific chemical reaction in your body happen thousands of times faster than it would on its own.
- [Epigenetic clock](https://upstreamlongevity.com/glossary/epigenetic-clock): An epigenetic clock is a test that estimates how old your body is biologically, rather than in birthdays, by reading chemical marks on your DNA.
- [Free radicals](https://upstreamlongevity.com/glossary/free-radicals): Free radicals are unstable molecules that can damage whatever they bump into, including DNA, proteins and cell walls, but in small amounts your body also uses them as important signals.
- [Gene](https://upstreamlongevity.com/glossary/gene): A gene is a stretch of DNA that holds the instructions for making one specific product, usually a protein your body needs.
- [Genome](https://upstreamlongevity.com/glossary/genome): A genome is the complete set of DNA instructions an organism carries, every recipe in the book, plus all the pages in between.
- [Glycogen](https://upstreamlongevity.com/glossary/glycogen): Glycogen is the form in which your body stores sugar, packed in your liver and muscles as a quick-access energy reserve.
- [Hallmarks of aging](https://upstreamlongevity.com/glossary/hallmarks-of-aging): The hallmarks of aging are the 12 main biological processes that scientists agree drive aging, from damage to DNA to slowing cellular recycling and chronic inflammation.
- [HbA1c](https://upstreamlongevity.com/glossary/hba1c): HbA1c is a blood test that shows your average blood sugar over roughly the past three months.
- [Heavy metals](https://upstreamlongevity.com/glossary/heavy-metals): Heavy metals such as lead, mercury and arsenic are toxic elements that can build up in the body over time and damage the brain, nerves, kidneys and heart.
- [Hippocampus](https://upstreamlongevity.com/glossary/hippocampus): The hippocampus is a small, seahorse-shaped region deep in the brain that turns new experiences into lasting memories and helps you find your way around.
- [Hormone](https://upstreamlongevity.com/glossary/hormone): A hormone is a chemical messenger made in one part of the body and carried in the blood to tell other parts what to do.
- [IGF-1](https://upstreamlongevity.com/glossary/igf-1): IGF-1 is a hormone, a chemical messenger, that tells cells throughout your body to grow and divide.
- [Inflammation](https://upstreamlongevity.com/glossary/inflammation): Inflammation is your body's alarm-and-repair response: immune cells rush to a problem, fight it and start repairs, and then the alarm is supposed to switch off.
- [Insulin](https://upstreamlongevity.com/glossary/insulin): Insulin is a hormone, a chemical messenger made by the pancreas, that tells your cells to take sugar out of the blood and store energy.
- [Insulin resistance](https://upstreamlongevity.com/glossary/insulin-resistance): Insulin resistance is when your cells stop responding well to insulin, so your body has to make more and more of it to keep blood sugar under control.
- [Intermittent fasting](https://upstreamlongevity.com/glossary/intermittent-fasting): Intermittent fasting means cycling between periods of eating and periods of not eating, for example eating only within an 8-hour window each day.
- [Ketones](https://upstreamlongevity.com/glossary/ketones): Ketones are a backup fuel your liver makes from fat when sugar is scarce, for example during fasting or a very low-carb diet; your brain and muscles can run on them.
- [Magnesium](https://upstreamlongevity.com/glossary/magnesium): Magnesium is a mineral your body uses in hundreds of chemical reactions, from making energy and building proteins to letting muscles and nerves relax.
- [Meta-analysis](https://upstreamlongevity.com/glossary/meta-analysis): A meta-analysis is a study that combines the results of many earlier studies on the same question to get a bigger, more reliable answer.
- [Metformin](https://upstreamlongevity.com/glossary/metformin): Metformin is a widely used, inexpensive prescription drug for type 2 diabetes that lowers blood sugar mainly by reducing how much sugar the liver releases.
- [Microbiome](https://upstreamlongevity.com/glossary/microbiome): The microbiome is the community of trillions of bacteria and other microbes living in and on your body, especially in your gut, that help digest food, train your immune system and make useful compounds.
- [Mitochondria](https://upstreamlongevity.com/glossary/mitochondria): Mitochondria are tiny structures inside your cells that turn the food you eat and the oxygen you breathe into energy your body can actually use.
- [Mitochondrial biogenesis](https://upstreamlongevity.com/glossary/mitochondrial-biogenesis): Mitochondrial biogenesis is the process by which your cells build brand-new mitochondria, the power plants that make energy.
- [Mitophagy](https://upstreamlongevity.com/glossary/mitophagy): Mitophagy is the process your cells use to find worn-out mitochondria, break them down and recycle their parts.
- [mTOR](https://upstreamlongevity.com/glossary/mtor): mTOR is a protein that acts as your cells' master growth switch: when nutrients are plentiful, it tells cells to build and grow; when it's quiet, they repair and recycle.
- [Mutation](https://upstreamlongevity.com/glossary/mutation): A mutation is a permanent change in the letters of DNA, like a typo that gets copied into every future edition of a recipe.
- [NAD⁺](https://upstreamlongevity.com/glossary/nad-plus): NAD⁺ is a small helper molecule that every cell needs to turn food into energy and to power its repair crews.
- [Naegleria fowleri](https://upstreamlongevity.com/glossary/naegleria-fowleri): Naegleria fowleri is a rare, single-celled organism found in warm fresh water and soil that can cause a deadly brain infection if water containing it goes up the nose.
- [Nasal irrigation](https://upstreamlongevity.com/glossary/nasal-irrigation): Nasal irrigation means rinsing your nasal passages with salt water, using a neti pot or squeeze bottle, to clear mucus, allergens and irritants.
- [Neuron](https://upstreamlongevity.com/glossary/neuron): A neuron is a nerve cell: a specialized cell that sends electrical and chemical signals to other cells, carrying every thought, feeling and movement.
- [NMN](https://upstreamlongevity.com/glossary/nmn): NMN is a small molecule your body converts directly into NAD⁺, the helper molecule cells need to make energy and run repairs.
- [Nucleus](https://upstreamlongevity.com/glossary/nucleus): The nucleus is the control center of a cell: a walled-off compartment where your main DNA is stored, protected and read.
- [Omega-3](https://upstreamlongevity.com/glossary/omega-3): Omega-3s are a family of healthy fats, found mainly in oily fish, that your body builds into cell walls and uses to help switch inflammation off.
- [Piperine](https://upstreamlongevity.com/glossary/piperine): Piperine is the compound that makes black pepper hot, added to turmeric supplements because it slows the body's breakdown of curcumin.
- [Placebo](https://upstreamlongevity.com/glossary/placebo): A placebo is a dummy treatment, like a sugar pill, that looks exactly like the real thing but contains nothing active, used in studies to see whether the real treatment does anything extra.
- [Polyphenols](https://upstreamlongevity.com/glossary/polyphenols): Polyphenols are a huge family of plant compounds, giving many fruits, vegetables, tea, coffee and olive oil their color and bitterness, that plants use to protect themselves.
- [Protein](https://upstreamlongevity.com/glossary/protein): Proteins are the molecular machines and building blocks of your body: they build muscle and skin, carry oxygen, fight infections and run almost every chemical job in your cells.
- [Randomized controlled trial](https://upstreamlongevity.com/glossary/randomized-controlled-trial): A randomized controlled trial is a study where people are assigned by chance, like a coin flip, to get either the treatment or a comparison such as a placebo, so any difference can be credited to the treatment.
- [Rapamycin](https://upstreamlongevity.com/glossary/rapamycin): Rapamycin is a prescription drug that turns down mTOR, the cell's growth switch; it's used to prevent organ transplant rejection and is studied as a possible anti-aging drug.
- [Rasayana](https://upstreamlongevity.com/glossary/rasayana): Rasayana is the branch of Ayurveda devoted to rejuvenation and long life, using herbs, diet and daily practices meant to strengthen the body and slow decline.
- [Resveratrol](https://upstreamlongevity.com/glossary/resveratrol): Resveratrol is a compound that plants like grapes make to protect themselves from stress, once hailed as an anti-aging molecule because it extended life in yeast.
- [Sarcopenia](https://upstreamlongevity.com/glossary/sarcopenia): Sarcopenia is the gradual loss of muscle mass, strength and function with age, to the point where it starts to affect everyday life.
- [Shilajit](https://upstreamlongevity.com/glossary/shilajit): Shilajit is a sticky, tar-like resin that seeps from rocks in high mountains such as the Himalayas, used in Ayurveda as a rejuvenating tonic and rich in fulvic acid and minerals.
- [Sirtuins](https://upstreamlongevity.com/glossary/sirtuins): Sirtuins are a family of proteins that help cells manage stress, repair and energy use, and they need NAD⁺ as fuel to work.
- [Spermidine](https://upstreamlongevity.com/glossary/spermidine): Spermidine is a natural compound found in every living cell and in foods like wheat germ, soybeans and aged cheese, that switches on autophagy, the cell's recycling system.
- [Statins](https://upstreamlongevity.com/glossary/statins): Statins are common prescription drugs that lower cholesterol by slowing its production in the liver, which reduces the risk of heart attacks and strokes.
- [Taurine](https://upstreamlongevity.com/glossary/taurine): Taurine is a small nutrient-like molecule, found mainly in fish, seafood and meat, that helps cells balance fluids and minerals and supports the heart, eyes and digestion.
- [Triphala](https://upstreamlongevity.com/glossary/triphala): Triphala is a traditional Ayurvedic blend of three dried fruits, amla, bibhitaki and haritaki, used mainly as a gentle digestive aid and tonic.
- [Vitamin D](https://upstreamlongevity.com/glossary/vitamin-d): Vitamin D is a vitamin your skin makes from sunlight that works like a hormone, helping your body absorb calcium and keeping your immune system balanced.
- [Vitamin K2](https://upstreamlongevity.com/glossary/vitamin-k2): Vitamin K2 is a form of vitamin K that activates proteins which pull calcium into bones and help keep it out of artery walls.
- [VO₂max](https://upstreamlongevity.com/glossary/vo2max): VO₂max is the maximum amount of oxygen your body can take in and use during all-out exercise, and it's one of the best single measures of fitness.
- [Zone 2](https://upstreamlongevity.com/glossary/zone-2): Zone 2 is a moderate, steady exercise intensity where you're breathing harder but can still talk in full sentences.

## About

- [About Upstream Longevity](https://upstreamlongevity.com/about): Upstream Longevity is an independent blog by curious non-doctors who trace aging to its root cause, explain it simply and grade the evidence honestly.
- [Affiliate Disclosure](https://upstreamlongevity.com/affiliate-disclosure): How Upstream Longevity handles affiliate links and partnerships, and why they never influence our conclusions or evidence grades.
- [How We Research](https://upstreamlongevity.com/how-we-research): How Upstream Longevity researches and writes: the upstream method, evidence grades A to D, source checking, AI-assisted research and our corrections policy.
- [Medical Disclaimer](https://upstreamlongevity.com/medical-disclaimer): Upstream Longevity is educational content written by non-doctors. It is not medical advice. Read our full medical disclaimer.
- [Privacy Policy](https://upstreamlongevity.com/privacy): How Upstream Longevity collects and uses data: newsletter email addresses and anonymous analytics. We never sell your data.