Glossary
Longevity science, explained simply
BDNF, NAD⁺, mTOR, autophagy… Every term in one plain sentence, with an everyday analogy and why it matters for aging. No biology degree required.
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AdaptogenAn adaptogen is an herb or compound claimed to help the body adapt to stress and restore balance, such as ashwagandha, rhodiola or ginseng.Amino acidsAmino acids are the small building blocks that link together in chains to form proteins, the molecular machines and structures of your body.AMPKAMPK 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.AntioxidantsAntioxidants are compounds that neutralize free radicals, the unstable molecules that can damage cells.AshwagandhaAshwagandha 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.ATPATP 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.AutophagyAutophagy is the recycling system inside your cells: it collects worn-out and broken parts, breaks them down and reuses the materials.AyurvedaAyurveda 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.
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BDNFBDNF 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.BerberineBerberine 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.BioavailabilityBioavailability is how much of something you swallow actually gets absorbed and reaches your bloodstream in a usable form.Brown fatBrown fat is a special type of body fat packed with mitochondria that burns energy to produce heat instead of storing it.
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Calorie restrictionCalorie restriction means eating noticeably fewer calories than usual, often 10 to 30 percent less, while still getting all the nutrients you need.CoQ10CoQ10 is a molecule inside your mitochondria that helps pass energy along the assembly line that recharges ATP, and it also works as an antioxidant.CortisolCortisol 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.CreatineCreatine is a natural compound that muscles and the brain use as a fast backup energy supply, instantly recharging ATP, the molecule cells run on.CurcuminCurcumin 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.
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DNADNA 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".DysbiosisDysbiosis 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.
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EnzymeAn 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 clockAn epigenetic clock is a test that estimates how old your body is biologically, rather than in birthdays, by reading chemical marks on your DNA.
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GeneA gene is a stretch of DNA that holds the instructions for making one specific product, usually a protein your body needs.GenomeA genome is the complete set of DNA instructions an organism carries, every recipe in the book, plus all the pages in between.GlycogenGlycogen is the form in which your body stores sugar, packed in your liver and muscles as a quick-access energy reserve.
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Hallmarks of agingThe 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.HbA1cHbA1c is a blood test that shows your average blood sugar over roughly the past three months.Heavy metalsHeavy 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.HippocampusThe 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.HormoneA hormone is a chemical messenger made in one part of the body and carried in the blood to tell other parts what to do.
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IGF-1IGF-1 is a hormone, a chemical messenger, that tells cells throughout your body to grow and divide.InflammationInflammation 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.InsulinInsulin 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 resistanceInsulin 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 fastingIntermittent fasting means cycling between periods of eating and periods of not eating, for example eating only within an 8-hour window each day.
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MagnesiumMagnesium is a mineral your body uses in hundreds of chemical reactions, from making energy and building proteins to letting muscles and nerves relax.Meta-analysisA meta-analysis is a study that combines the results of many earlier studies on the same question to get a bigger, more reliable answer.MetforminMetformin is a widely used, inexpensive prescription drug for type 2 diabetes that lowers blood sugar mainly by reducing how much sugar the liver releases.MicrobiomeThe 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.MitochondriaMitochondria 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 biogenesisMitochondrial biogenesis is the process by which your cells build brand-new mitochondria, the power plants that make energy.MitophagyMitophagy is the process your cells use to find worn-out mitochondria, break them down and recycle their parts.mTORmTOR 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.MutationA mutation is a permanent change in the letters of DNA, like a typo that gets copied into every future edition of a recipe.
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NAD⁺NAD⁺ is a small helper molecule that every cell needs to turn food into energy and to power its repair crews.Naegleria fowleriNaegleria 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 irrigationNasal irrigation means rinsing your nasal passages with salt water, using a neti pot or squeeze bottle, to clear mucus, allergens and irritants.NeuronA neuron is a nerve cell: a specialized cell that sends electrical and chemical signals to other cells, carrying every thought, feeling and movement.NMNNMN is a small molecule your body converts directly into NAD⁺, the helper molecule cells need to make energy and run repairs.NucleusThe nucleus is the control center of a cell: a walled-off compartment where your main DNA is stored, protected and read.
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PiperinePiperine is the compound that makes black pepper hot, added to turmeric supplements because it slows the body's breakdown of curcumin.PlaceboA 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.PolyphenolsPolyphenols 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.ProteinProteins 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.
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Randomized controlled trialA 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.RapamycinRapamycin 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.RasayanaRasayana 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.ResveratrolResveratrol 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.
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SarcopeniaSarcopenia is the gradual loss of muscle mass, strength and function with age, to the point where it starts to affect everyday life.ShilajitShilajit 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.SirtuinsSirtuins are a family of proteins that help cells manage stress, repair and energy use, and they need NAD⁺ as fuel to work.SpermidineSpermidine 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.StatinsStatins are common prescription drugs that lower cholesterol by slowing its production in the liver, which reduces the risk of heart attacks and strokes.
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TaurineTaurine 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.TriphalaTriphala is a traditional Ayurvedic blend of three dried fruits, amla, bibhitaki and haritaki, used mainly as a gentle digestive aid and tonic.
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Vitamin DVitamin 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 K2Vitamin K2 is a form of vitamin K that activates proteins which pull calcium into bones and help keep it out of artery walls.VO₂maxVO₂max 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.