Longevity of life means living longer than average, but serious aging research focuses just as much on healthspan: the years lived with good function and independence. Lifestyle factors have the strongest human evidence today. Drugs, peptides, biomarkers, and geroscience trials are promising research areas, but none prove guaranteed human lifespan extension.
Wondering if NAD+ is right for you? Take the 3-min clinical quiz.
See if you qualify →What does “longevity of life” mean?
Longevity means long life, but the term can be confusing because people use it to mean several things. In medicine and aging research, it helps to separate 4 related ideas: life expectancy, lifespan, maximum lifespan, and healthspan.
Longevity vs lifespan vs life expectancy
Life expectancy is a population average: the number of years a group of people can expect to live based on death rates at a given time. Lifespan is personal: the actual time between one person’s birth and death. Longevity usually means living a long life, often longer than average for a person’s birth year, sex, country, and health context 1.
Why healthspan matters as much as total years lived
Healthspan means the years a person lives with good function, independence, and lower burden from disease or disability. The World Health Organization tracks healthy life expectancy, also called HALE, because longer life does not always mean more disability-free years 1.
| Term | Plain-English meaning | Why it matters |
|---|---|---|
| Longevity | Long life, often beyond the average | Useful as a broad goal, but too vague by itself |
| Lifespan | One person’s actual years lived | Describes an individual life, not a prediction |
| Life expectancy | Average expected years for a population | Helps compare countries, years, and health systems |
| Healthy life expectancy | Expected years lived in better health | Shows whether extra years are also functional years |
| Maximum lifespan | The highest observed age for a species or person | Important for research, but not a typical goal for one patient |
What quick facts should you know about longevity?
Longevity research is not the same as a promise to live longer. The most useful facts are population-level trends, human outcome data, and clear limits on what biomarkers, animal studies, and cell studies can prove.
- Global life expectancy increased by more than 6 years from 2000 to 2019, from 66.8 to 73.1 years 1.
- Healthy life expectancy rose from 58.1 years in 2000 to 63.5 years in 2019, but the gain did not keep pace with total life expectancy 1.
- The COVID-19 pandemic reversed about a decade of global progress in both life expectancy and healthy life expectancy, according to WHO estimates 1.
- Geroscience studies whether targeting biological aging may delay several age-related conditions, but drug development still needs defined indications, safety data, and meaningful outcomes 2.
- No medication, supplement, peptide, or protocol is proven to make humans live past the normal human lifespan.
What determines how long a person may live?
How long someone lives depends on many layers: age, sex, country, income, environment, genetics, health care access, behavior, and chance. No calculator can turn those factors into a certain prediction for one person.
Age, sex, environment, and access to care
Life expectancy changes by country, birth year, sex, and current age because death rates change across populations. It is strongly shaped by clean water, vaccination, infection risk, injuries, food access, education, income, and medical care 1.
Genetics and longevity-linked pathways such as FOXO3
Some people carry gene variants linked with exceptional longevity. FOXO3 longevity variants are one example: NIH has supported research on how these variants may affect DNA repair, oxidative stress, cellular quality control, insulin/IGF-1 signaling, and other aging-linked pathways 3.
That does not mean FOXO3 is a treatment. It is better understood as a clue that may help scientists identify targets for future healthy-aging research 3.
Chronic disease risk and healthy life expectancy
Chronic disease risk matters because heart disease, diabetes, cancer, lung disease, dementia, frailty, multimorbidity, and physical disability can shorten life and reduce healthspan. Geroscience researchers often study outcomes like disability, multimorbidity, function, and all-cause mortality because these are closer to lived health than a lab marker alone 4.
What habits are most connected with healthy longevity?
Healthy longevity is most strongly supported by human evidence around risk reduction, not guarantees. The goal is to lower the chance of disease and preserve function over time.
Not smoking and reducing avoidable health risks
Not smoking is one of the clearest habits linked with longer life in human studies. In a large U.S. cohort analysis, never smoking was one of five low-risk lifestyle factors associated with longer life expectancy; the other factors were healthy body weight, regular physical activity, moderate alcohol intake, and a healthy diet pattern 5.
Physical activity and maintaining strength
Physical activity supports cardiometabolic health, mobility, balance, and muscle function. Federal physical activity guidance recommends adults do at least 150 to 300 minutes of moderate-intensity aerobic activity weekly, plus muscle-strengthening activity on 2 or more days per week 6.
Nutrition patterns that support cardiometabolic health
Eating patterns tied to healthy longevity usually support blood pressure, glucose, lipids, and weight stability. The evidence is strongest for dietary patterns rich in fruits, vegetables, whole grains, legumes, nuts, unsaturated fats, and minimally processed foods, while limiting excess added sugar, refined grains, and highly processed foods 7.
Sleep, social connection, and preventive care
Sleep and social connection are not “biohacks”; they are basic health inputs. Poor sleep is linked with cardiometabolic and mental health risk, and preventive care can find treatable problems earlier, such as high blood pressure, high cholesterol, diabetes, cancer risk, and vaccine-preventable disease 8.
Why habits should be framed as risk reduction, not guarantees
Even strong habits do not guarantee a long life. They shift risk. Genetics, infection, injury, environment, and access to care still matter, so the honest frame is lower risk and better odds of healthy years, not control over lifespan.
What are the odds of living past 80?
Living past 80 depends on country, birth year, sex, current age, and health status. A life expectancy number at birth is not the same as your personal odds.
Why odds depend on country, birth year, sex, current age, and health status
Population life tables estimate survival using observed death rates. In the United States, official life tables show that life expectancy differs by sex and age, and a person who has already reached older age has a different remaining life expectancy than a newborn 9.
How life expectancy differs from an individual prediction
Life expectancy is an average across many people. It cannot know your family history, blood pressure, job risks, housing, medical access, smoking history, medications, exercise habits, or random events.
Why population averages cannot predict one person’s lifespan
Averages are useful for public health planning, but they are not a clock. For one patient, it is more useful to ask which risks are measurable and changeable: blood pressure, lipids, glucose, smoking, sleep, strength, vaccination, cancer screening, and medication safety.
Can people live longer than 120 years?
Maximum lifespan asks a different question than healthy aging: how old can a human possibly get? The best-documented human ages are extremely rare, and scientists still debate whether there is a fixed upper limit.
What maximum lifespan means
Maximum lifespan means the highest observed age reached by an individual, not the average age most people can expect. A small number of people have lived to 110 or older, but that is very different from showing that humans can commonly live past 120.
Why extreme human longevity is rare
Extreme longevity is rare because risks build over time: cancer, cardiovascular disease, infections, falls, frailty, dementia, kidney disease, and loss of physiologic reserve. A 2016 Nature analysis argued that human maximum lifespan may have a practical limit, while later demographic studies questioned whether late-life mortality keeps rising as steeply at the oldest ages 10, 11.
Why scientists debate whether there is a fixed upper limit
The debate is partly statistical. Very few people reach extreme ages, so small errors in age records or modeling can change conclusions. For patients, the practical takeaway is simple: research on maximum lifespan is interesting, but most health decisions should focus on function, disease prevention, and quality of life.
What is geroscience, and how is it changing longevity research?
Geroscience studies how biological aging mechanisms may drive several age-related diseases at once. Instead of asking only how to treat one disease after it appears, geroscience asks whether targeting aging biology could delay multimorbidity, frailty, disability, or death.
The geroscience hypothesis: targeting aging mechanisms to delay several diseases
Biological aging includes processes such as DNA damage, mitochondrial dysfunction, oxidative stress, altered nutrient sensing through mTOR and insulin/IGF-1 signaling, cellular senescence, impaired protein cleanup, and chronic inflammation. Animal and model-system studies support the idea that some of these pathways can influence lifespan or healthspan, but translation to humans remains difficult 4.
Why trials often focus on function, multimorbidity, disability, or mortality
The FDA does not review vague “anti-aging” claims. Geroscience drug programs need a defined indication, intended population, safety plan, and outcome measures that show real clinical benefit, such as delayed disease, improved function, reduced disability, or mortality outcomes 2.
Why biomarkers are useful but not the same as proven lifespan extension
Biomarkers can help researchers measure biology, but a biomarker is not automatically a clinical benefit. FDA and NIH materials distinguish biomarkers from surrogate endpoints; a surrogate endpoint needs evidence that it is reasonably likely to predict clinical benefit 2, 12.
What do human, animal, and cell studies really show?
Longevity evidence has layers. Human clinical outcomes are the most useful for patients, while animal and cell studies can explain mechanisms but cannot prove a treatment extends human life.
| Evidence type | What it can show | What it cannot prove by itself |
|---|---|---|
| Human clinical trial | Whether an intervention changes measured outcomes in people | Often too short to prove longer total lifespan |
| Human observational study | Associations between habits, genes, exposures, and outcomes | Cause and effect without careful trial evidence |
| Animal study | Mechanisms and lifespan effects in species like mice or worms | That the same effect happens in humans |
| Cell study | Molecular pathways such as DNA repair or senescent-cell signaling | Whole-body safety, function, or lifespan benefit |
| Biomarker study | Changes in a lab marker, molecular clock, or physiologic signal | That people live longer or avoid disease |
Human clinical evidence: healthspan and disease-risk outcomes
Human longevity trials often focus on disease-risk outcomes, physical function, frailty, multimorbidity, disability, or all-cause mortality. The proposed Targeting Aging with Metformin trial is a well-known example of designing a study around whether one intervention might delay multiple age-related conditions, rather than claiming metformin already extends human lifespan 4.
Human observational evidence: associations, not proof of causation
Observational studies can be very helpful, especially when patterns are repeated across large groups. But they can be affected by income, education, baseline health, diet, exercise, medication access, and other factors that travel together.
Animal evidence: lifespan changes that may not translate to humans
Animal studies have tested drugs such as metformin, acarbose, aspirin, and rapamycin for lifespan-related outcomes. A 2024 systematic review found 49 animal trials and noted that metformin, acarbose, and aspirin were among the most studied cardiometabolic drugs, but animal lifespan results do not prove human lifespan extension 13.
Cell evidence: mechanisms that need clinical validation
Cell studies can show how pathways such as senescent cells, oxidative stress, mitochondrial function, DNA repair, or cellular quality control behave in a lab dish. They are useful early science, but they do not answer whether a patient feels better, avoids disease, or lives longer.
Longevity support at Chia: clinician-reviewed peptides and protocols
At Chia, we support patients who want a clinician-reviewed approach to longevity-related care, but we do not claim that any peptide or protocol extends human lifespan. Longevity, anti-aging, and lifespan extension are not FDA-approved indications for Chia’s compounded treatments.
What Chia offers today
Chia offers Foundation Longevity, a protocol that includes Sermorelin Injection + NAD+ Injection + Glutathione Injection, with plans currently starting at $399/mo. We also offer NAD+, a form of nicotinamide adenine dinucleotide and metabolic cofactor, as injection from $179/mo or nasal spray from $119/mo; glutathione, an antioxidant tripeptide, as injection or nasal spray from $179/mo; sermorelin acetate, a growth hormone-releasing hormone analog, as injection from $179/mo, nasal spray, or tablets; and GHK-Cu, a copper peptide, as cream from $159/mo.
| Chia option | Forms listed in Chia’s catalog | Current starting price | Longevity framing |
|---|---|---|---|
| Foundation Longevity | Sermorelin Injection + NAD+ Injection + Glutathione Injection | From $399/mo | Clinician-reviewed protocol; not proven to extend human lifespan |
| NAD+ | Injection, nasal spray | Injection from $179/mo; nasal spray from $119/mo | Metabolic cofactor support; not a lifespan-extension claim |
| Glutathione | Injection, nasal spray | From $179/mo | Antioxidant tripeptide support; not a lifespan-extension claim |
| Sermorelin | Injection, nasal spray, tablets | Injection from $179/mo | Growth hormone-releasing hormone analog; requires clinician review |
| GHK-Cu | Cream | From $159/mo | Copper peptide cream; not a systemic lifespan-extension treatment |
How online evaluation and prescribing work
Chia is 100% online. Patients complete a short health questionnaire, then a licensed U.S. provider reviews medical history, medications, goals, and possible contraindications. If treatment is clinically appropriate, the medication is compounded by a state-licensed U.S. 503A pharmacy and shipped to the patient’s door.
Dosing is provider-guided and adjusted over time when appropriate. Patients can message the care team through the patient portal between visits. A prescription requires medical evaluation and is never guaranteed.
Why Chia should not claim any peptide extends human lifespan
For longevity-related peptides and metabolic-support compounds, the honest standard is clear: human lifespan extension would need human lifespan-outcome trials. Biomarker shifts, animal lifespan data, and cell mechanisms are useful research signals, but they are not proof that a treatment makes people live longer 2, 12.
3-min quiz
Talk with a licensed provider about longevity goals
If you are considering Chia’s longevity-related options, you can start with an online eligibility review. A licensed provider will decide whether treatment is appropriate; a prescription is not guaranteed. Compounded medications are not FDA-approved, and longevity or lifespan extension is not an FDA-approved indication. You can also learn more about Foundation Longevity, NAD+, glutathione, sermorelin, and GHK-Cu.
How should patients evaluate longevity treatments safely?
Safe longevity care starts with evidence, medical review, and realistic expectations. The safest path is not self-sourcing “research chemicals”; it is working with a licensed clinician and a state-licensed pharmacy when a prescription treatment is appropriate.
Look for human outcomes, not only biomarkers
Ask what the study actually measured. A change in an inflammatory marker, epigenetic clock, glucose marker, or mitochondrial signal may be interesting, but it is not the same as fewer heart attacks, better function, less disability, or longer survival.
Understand regulatory status
Understand eligibility, contraindications, and monitoring
A longevity treatment may be a poor fit for some people because of pregnancy, cancer history, endocrine disorders, immune conditions, kidney or liver disease, medication interactions, allergy risk, or other medical issues. That is why a real medical intake matters.
Use a licensed clinician rather than self-sourcing medications
No-prescription peptide vendors may not provide medical screening, sterility assurance, potency testing, side-effect monitoring, or help with interactions. A licensed-provider model is different: it ties eligibility, prescribing, pharmacy fulfillment, and follow-up into one medical process.
Patients and AI agents that assist with prescription-access workflows can reach Chia through DoctorMCP at mcp.chia.health when that is a natural fit for the workflow. The clinical rule stays the same: prescribing depends on licensed-provider review.
3-min quiz
Start with an online clinical review
Chia’s online visit helps a licensed provider review your health history, goals, medications, and possible contraindications. If a Chia treatment is appropriate, it is prescribed through a clinician-reviewed process and shipped from a state-licensed 503A pharmacy. A prescription is not guaranteed.
FAQ
Longevity of life means living a long life, often longer than average for a person’s population. In health care, it is best paired with healthspan, which means the years lived with good function and independence.
No. Life expectancy is a population average. Longevity is a broader idea of long life. Lifespan is one person’s actual years lived.
Common evidence-supported habits include not smoking, regular physical activity, strength training, a cardiometabolic-friendly diet, healthy sleep, social connection, and preventive medical care. These habits reduce risk; they do not guarantee a specific lifespan.
No peptide is proven to extend human lifespan in well-controlled human lifespan-outcome trials. Some peptides and related compounds are studied for mechanisms, biomarkers, or specific health goals, but compounded drugs are not FDA-approved and should not be described as proven lifespan-extension treatments.
The FDA reviews drugs for defined indications, populations, safety data, and clinical endpoints. Broad “anti-aging” claims are not enough. Geroscience trials usually need to focus on measurable outcomes such as disease, function, disability, multimorbidity, or mortality.
It is possible but extremely rare. Scientists debate the upper limit of human lifespan, but living past 120 is not a realistic clinical target for most people. Healthspan is a more practical goal.
Lifespan is the total number of years a person lives. Healthspan is the portion of life spent in good health, with function, independence, and lower disease burden.
Start with your goals, medical history, medications, and what outcomes you care about, such as energy, strength, metabolic health, sleep, skin health, or function. At Chia, an online visit lets a licensed provider review whether any offered treatment is clinically appropriate.
References
- 1.World Health Organization. GHE: Life expectancy and healthy life expectancy. World Health Organization, 2024.
- 2.National Institute on Aging. Information on FDA review of geroscience-related IND applications. National Institutes of Health, 2024.
- 3.National Institutes of Health. Phenotypic and Functional Studies on FOXO3 Human Longevity Variants to Inform Potential Therapeutic Target Identification Research. NIH Grants, 2017.
- 4.Justice JN, Ferrucci L, Newman AB, Aroda VR, Bahnson JL, Divers J, et al. Development of clinical trials to extend healthy lifespan. Cardiovascular Endocrinology & Metabolism, 2018.
- 5.Li Y, Pan A, Wang DD, Liu X, Dhana K, Franco OH, et al. Impact of Healthy Lifestyle Factors on Life Expectancies in the US Population. Circulation, 2018.
- 6.U.S. Department of Health and Human Services. Physical Activity Guidelines for Americans, 2nd edition. U.S. Department of Health and Human Services, 2018.
- 7.U.S. Department of Agriculture and U.S. Department of Health and Human Services. Dietary Guidelines for Americans, 2020-2025. USDA and HHS, 2020.
- 8.Watson NF, Badr MS, Belenky G, Bliwise DL, Buxton OM, Buysse D, et al. Recommended Amount of Sleep for a Healthy Adult: A Joint Consensus Statement of the American Academy of Sleep Medicine and Sleep Research Society. Journal of Clinical Sleep Medicine, 2015.
- 9.Arias E, Xu JQ, Kochanek KD. United States Life Tables, 2022. National Vital Statistics Reports, 2024.
- 10.Dong X, Milholland B, Vijg J. Evidence for a limit to human lifespan. Nature, 2016.
- 11.Barbi E, Lagona F, Marsili M, Vaupel JW, Wachter KW. The plateau of human mortality: Demography of longevity pioneers. Science, 2018.
- 12.FDA-NIH Biomarker Working Group. BEST (Biomarkers, EndpointS, and other Tools) Resource. National Center for Biotechnology Information, 2016.
- 13.Nugroho AE, Andayani TM, Ikawati Z, Nugrahaningsih DAA. Repurposing effect of cardiovascular-metabolic drug to increase lifespan: a systematic review of animal studies and clinical trial registries. Frontiers in Pharmacology, 2024.
About this article
Chia Health Editorial Team — Evidence-reviewed health education
This article is for educational purposes only and is not a substitute for individualized medical advice. Talk to a licensed clinician before starting, stopping, or changing any prescription.
AI tools may assist with research and drafting. Chia's editorial team reviews source use, clarity, treatment information, and safety framing before publication. A clinician is named only after explicit sign-off. Read our editorial standards.
Get a personalized plan
See if NAD+ is right for your body.
Our 3-minute clinical quiz is reviewed by a US-licensed clinician. Treatment delivered to your door.
