Submitted:
23 July 2025
Posted:
24 July 2025
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Abstract
Keywords:
2. Introduction
2.1. Defining HLFD
3. There Is No Program for Aging: The Fundamental Paradigm Shift
| Theory | Description | Relation to HLFD | Reference |
|---|---|---|---|
| Wear and Tear | Aging as physical breakdown over time | Misinterprets systemic dysregulation as time | [54] |
| Free Radical Theory | Damage from oxidative stress causes aging | Links to HLFD via Klotho’s antioxidant role | [31] |
| HLFD (Proposed) | Systemic dysregulation, not time-dependent | Targets Klotho as one of the most promising tools | [75,77] |
4. The Miracle of Life: The Base State of Matter Is Abiotic
5. Creation: Growth Cycles of Human Organisms
- Conception to Birth: Rapid cellular division, highest metabolic rates, and extreme stem cell activity [47].
- Birth to Age 2: Fast growth rate, highest energy utilization per body weight [78].
- Childhood (2–12 years): Slower but stable growth, robust immune function [118].
- Puberty (12–18 years): Hormonal surge, peak regenerative capacity, and the onset of reproductive capability [17].
- Healthy Life Plateau (18–35 years): Maximum metabolic efficiency, peak reproductive and systemic health [74].
- Post-Plateau (35+ years): The system remains functional if regulatory mechanisms like Klotho remain stable; otherwise, HLFD develops [75].
6. The Combustive Nature of Life: Cellular Turnover and Health: Our Cells ARE Programmed to Die so that We May Remain Renewed
6.1. Cellular Turnover as the Foundation of Health
- Young individuals exhibit rapid cell proliferation, differentiation, and clearance [5].
- High mitochondrial activity supports fast energy production, fueling this renewal cycle [79].
- Growth hormone and anabolic signaling pathways (e.g., mTOR, IGF-1) are active, promoting tissue regeneration [30].
- Decline in cellular turnover with age is linked to degeneration, immune dysfunction, and disease [85].
- Apoptosis removes dysfunctional cells, preventing cancer and systemic dysfunction [69].
- Autophagy recycles cellular components, maintaining cellular efficiency [92].
- Phagocytosis clears dead cells, preventing toxic accumulation [108].
- When these processes slow, senescent cells accumulate, secreting inflammatory factors (SASP) that contribute to aging and chronic disease [21].
6.2. The Problem with Longevity Strategies That Slow Metabolism
- Fasting suppresses mTOR and growth signals, reducing cell proliferation and turnover [89].
- It promotes quiescence, slowing metabolism and reducing energy expenditure [40].
- A truly effective approach would actively promote new cell generation and clearance, maintaining a constant renewal cycle [107].
6.3. A New Model: Maintaining Cellular Turnover for Longevity
- Encouraging cell proliferation through appropriate nutrient intake (protein, amino acids) [102].
- Enhancing autophagy and apoptosis through exercise, which naturally stimulates cellular clearance [58].
- Avoiding prolonged caloric restriction, which signals the body to conserve resources rather than renew tissue [40].
- Supplementing Klotho levels as they decline with age to keep them in the optimal range to support healthy, aggressive, and continuous metabolic function [74].
- High mitochondrial turnover maintains energy production efficiency [127].
- Klotho serum level is essential for sustaining high metabolic activity [135].
- Avoiding interventions that downregulate metabolism (e.g., excessive fasting, long-term caloric restriction) [40].
- Optimizing immune function helps remove damaged cells effectively [108].
- Chronic low-grade inflammation (often seen with accumulated senescent cells) should be prevented through active clearance rather than mere suppression [41].
- Klotho is known to support phagocytosis and promote inflammation resolution [83].
7. Evidence That Aging Is Not Time-Dependent
7.1. Centenarians vs. Median Life Expectancy
| Rank | Name | Age | Country | Reference |
|---|---|---|---|---|
| 1 | Inah Canabarro Lucas | 116 years, 261 days | Brazil | [46] |
| 2 | Ethel Caterham | 115 years, 187 days | United Kingdom | [46] |
| 3 | Okagi Hayashi | 115 years, 175 days | Japan | [46] |
| 4 | Elizabeth Francis | 115 years, 214 days | United States | [46] |
| 5 | Juan Vicente Pérez Mora | 115 years, 273 days | Venezuela | [46] |
| 6 | Noeme da Silveira Freitas | 115 years, 81 days | Brazil | [46] |
| 7 | Jeanne Bot | 115 years, 41 days | France | [46] |
| 8 | João Marinho Neto | 112 years, 142 days | Brazil | [46] |
| 9 | Eusebio Quintero López | 111 years, 355 days | Colombia | [46] |
| 10 | Manuel Benavente Sanhueza | 111 years, 341 days | Chile | [46] |
7.2. Examples of Non-Chronological Decline
- Hutchinson-Gilford Progeria Syndrome (HGPS): HGPS causes children to develop aging-like features (wrinkled skin, cardiovascular disease, and joint stiffness) within years of birth due to LMNA gene mutations disrupting nuclear architecture [48]. This is not accelerated aging but systemic dysregulation from defective DNA repair and cellular maintenance [35]. Klotho’s role in phosphate homeostasis via FGF23 signaling could mitigate vascular calcification in HGPS, as patients exhibit mineral imbalances [48,61]. Its decline may exacerbate DNA damage, given Klotho’s protective effects on genomic stability through oxidative stress reduction [95].
- Werner Syndrome (WS): WS triggers rapid decline in early adulthood (osteoporosis, cardiovascular disease, and metabolic failure) due to WRN gene mutations impairing DNA helicase function [100]. This dysregulation mimics aging phenotypes, not time-driven decay [50]. Klotho’s depletion increases DNA damage post-radiation, suggesting it could worsen WS’s repair deficits [95]. Its regulation of phosphate via FGF23 may address WS’s osteoporosis and calcification [61]. Hypogonadism in 80% of WS patients, linked to gonadal atrophy, aligns with Klotho’s hormonal regulation via insulin signaling, hinting at a fertility-HLFD connection [113].
- Bloom Syndrome (BS): BS, caused by BLM gene mutations, impairs DNA helicase activity, leading to genomic instability [129]. Patients exhibit premature aging traits (skin atrophy, cancer predisposition) by their 20s, with lifespans averaging 30–40 years [130]. This reflects dysregulation, not time, as DNA repair fails early [131]. Klotho’s antioxidant role via Mn-SOD modulation could reduce BS’s oxidative stress, a key driver of chromosomal breaks and cellular damage [135].
- Cockayne Syndrome (CS): CS results from ERCC6/8 mutations, disrupting nucleotide excision repair, causing children to show aged features (neurodegeneration, hearing loss, skeletal defects) by age 5–10, with lifespans rarely exceeding 20 [7,96]. This is repair failure, not chronological aging. Klotho’s regulation of phosphate via FGF23 could mitigate CS’s osteopenia, a bone mineralization defect linked to repair stress [61], while its mitochondrial protection via PGC-1α may reduce neuronal oxidative damage [31,76].
- Klotho Knockout Mice: Mice lacking Klotho exhibit a 10-fold lifespan reduction, developing osteoporosis, arteriosclerosis, and frailty within weeks [75]. This systemic failure, not time-dependent aging, stems from absent phosphate regulation (via FGF23) and mitochondrial collapse [61]. Infertility due to undeveloped reproductive organs further ties HLFD to dysregulation [75]. Klotho supplementation reverses these effects, proving treatability [61].
7.3. Microgravity: Spaceflight as an HLFD Model
7.4. NASA Twins Study: Microgravity’s Dysregulation with Control
8. Why Are We Here? The Purpose of Life
8.1. Reproduction and Systemic Health
- Women who conceive later in life tend to live longer, demonstrating that reproductive function is linked to systemic resilience; studies suggest genetic factors like telomere length may underlie this [103].
- Men with high testosterone and sperm motility show fewer age-related diseases, reinforcing that reproductive function is a marker of biological health; further research could quantify this link [67].
- Cellular Aging: Reproductive cells are sensitive to stressors like oxidative damage or poor nutrition [3]. When these cells falter, it reflects a systemic breakdown, as cellular health underpins both reproduction and survival [2]. Interestingly, these same stressors trigger Klotho upregulation [76]. Research suggests that as long as the system can produce enough Klotho to protect from these disruptions, the system seems to repair itself and continue to function properly [113].
- Life Cycle Patterns: In many species, once reproductive capacity wanes (e.g., post-menopause in humans or senescence and even sudden death in other animals), overall health declines more rapidly [37].
8.2. Queen Bees and Dominant Reproducers: Living Long as Reproductive Systems
- Alpha Wolves: In wolf packs, the alpha pair dominates breeding. Subordinates hunt and guard the pups, supporting the alphas’ reproductive role. Alphas often live longer and healthier due to their status [91].
- Meerkats: The dominant female reproduces while subordinates care for her pups. Her health and longevity trump theirs [26].
8.3. Sex and Gender Differences in Reproduction and Longevity
8.4. Cellular Drive: Reproduction at the Core
8.5. Asexual Organisms: Reproduction Without Mates
8.6. Humans Were Programmed to Reproduce Until Death
9. Species Demonstrating Reproduction Tied to Longevity
9.1. Animals: Longevity and Reproduction Patterns
-
Bowhead Whale (Balaena mysticetus):
- ○
- Lifespan: Over 200 years [45].
- ○
- Reproduction: Do not reach sexual maturity until around 25 years and can reproduce into their later decades, with calving intervals of 3–4 years. Evidence suggests females remain fertile for much of their lives. A 90-year-old female was found pregnant, and males show active spermatogenesis late in life [45].
- ○
-
Galápagos Tortoise (Chelonoidis nigra):
-
Ocean Quahog (Arctica islandica):
- ○
- Lifespan: Over 500 years [20].
- ○
- Reproduction: These clams are gonochoristic (separate sexes) and spawn annually after reaching maturity around 6–10 years. They release millions of gametes into the water, with no evidence of reproductive senescence. Samples from 200-year-olds show viable sperm and eggs [20].
- ○
- Tie to Longevity: Constant reproduction over centuries [20].
-
Naked Mole Rat (Heterocephalus glaber):
- ○
- Lifespan: Up to 37 years [18].
- ○
- Reproduction: Queens in their eusocial colonies breed continuously, producing litters of 10–20 pups every 80–90 days well into their 30s. Subordinates do not reproduce, but queens show no fertility drop-off [18].
- ○
- Tie to Longevity: Cancer resistance (via hyaluronan) and stable proteasomes keep them reproductively active [125].
-
Greenland Shark (Somniosus microcephalus):
- ○
- Lifespan: Estimated 272–512 years, based on radiocarbon dating of eye lenses [98].
- ○
- Reproduction: Sexual maturity hits late, around 150 years, and they are ovoviviparous, birthing live pups (10–20 per litter). Old females (300+ years) show ovarian activity, suggesting reproduction persists [98].
- ○
- Tie to Longevity: No reproductive shutdown [37].
9.2. Plants: Trees and Clonal Colonies: Reproduction Over Millennia
-
Great Basin Bristlecone Pine (Pinus longaeva):
- ○
- Lifespan: Up to 4,856 years (Methuselah) or more, possibly 5,000+ for some [80].
- ○
- Reproduction: These pines produce cones annually after maturity (50–100 years), with viable seeds even in their oldest specimens. Growth slows, but cone production persists; 3,000-year-olds still seed the landscape [80].
- ○
- Tie to Longevity: Constant reproduction over millennia, “programmed to live,” no senescence, just persistence [116].
-
Pando (Populus tremuloides):
- ○
- Lifespan: Estimated 14,000–16,000 years as a clonal colony; individual stems live ~130 years [93].
- ○
- Reproduction: This quaking aspen colony in Utah spreads via root suckers, sprouting new stems constantly. Sexual reproduction (seeds) is rare due to climate shifts, but clonal growth is relentless, with 80,000 years of potential if dated to its genetic origin [93].
- ○
-
Old Tjikko (Picea abies):
- ○
- Lifespan: 9,550 years via clonal roots; above-ground trunks cycle every ~600 years [99].
- ○
- ○
-
Llangernyw Yew (Taxus baccata):
- ○
- Lifespan: 4,000–5,000 years for this Welsh tree [124].
- ○
- Reproduction: Yews are dioecious; females produce berries (arils) with seeds annually into extreme age. Pollen from males remains viable too; 4,000-year-olds still contribute [124].
- ○
- Tie to Longevity: Lifelong seed output; reproduction drives vitality; life never quits [37].
-
General Sherman (Sequoiadendron giganteum):
9.3. Other Organisms: Corals, Sponges, and Beyond
-
Black Coral (Leiopathes spp.):
- ○
- Lifespan: Up to 4,270 years (Hawaii specimen) [109].
- ○
- Reproduction: These deep-sea corals release gametes annually or biennially, with colonies growing and spawning for millennia. No reproductive senescence observed [109].
- ○
- Tie to Longevity: Constant reproduction mirrors life’s persistence [116].
-
Glass Sponge (Hexactinellida):
- ○
- Lifespan: Over 2,300 years (Caribbean barrel sponges); some Pacific species may hit 10,000+ [90].
- ○
- Reproduction: Asexual budding and sexual gamete release persist throughout life. Old specimens remain reproductively active [90].
- ○
- Tie to Longevity: Lifelong reproduction; life keeps making more life [116].
-
Hydra (Hydra spp.):
9.4. Synthesis: Reproduction and Longevity Tied?
10. Klotho: The Master Regulator and Optimal Balance for Longevity
10.1. Klotho’s Role in Metabolism
10.2. Klotho and Autophagy: Facilitating Cellular Clearance
10.3. Klotho and the Immune System
10.4. Klotho as a Key to HLFD Treatment
10.5. Klotho’s Role in Longevity-Focused Research and Pathways
- Telomere Shortening as a Function of Dysregulation: Research suggests telomere shortening is a function of cellular dysregulation, driven by factors like oxidative stress and psychological stress, which exacerbate telomere attrition [34]. For instance, telomeres shorten in response to biochemical stressors (e.g., oxidative stress) and psychological stressors in a dose-response manner, as seen in high-stress caregivers [34]. Reduced Klotho levels contribute to telomere shortening [31]. Klotho plays a significant role in maintaining telomerase activity, the enzyme that extends telomeres [31]. Studies show that lower Klotho levels reduce telomerase activity, leading to shorter telomeres [84]. In cancer cells, Klotho suppresses TERT expression, reducing telomerase activity, as seen in colorectal, ovarian, and gastric cancer cells [9,112,126].
- Mitochondrial Health: Klotho is crucial for mitochondrial health, regulating oxidative stress and mitochondrial function, particularly in kidney disease [31]. Studies show Klotho modulates signaling pathways involving manganese-containing superoxide dismutase (Mn-SOD) and transcription factors FoxO and Nrf2, known antioxidant systems, and other mitochondrial function regulators like mitochondrial uncoupling protein 1 (UCP1), B-cell lymphoma-2 (BCL-2), and peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) [135]. In aged muscle progenitor cells, decreased α-Klotho levels were associated with vacuolated mitochondria and compromised cristae structure, which SS-31 treatment reversed, supporting Klotho’s role in mitochondrial energetics [115]. Klotho’s involvement in mitochondrial biogenesis is also noted in skeletal muscle function, highlighting its broader impact [11].
- Sirtuins: The evidence suggests that Klotho interacts with sirtuins, particularly SIRT1, a NAD+-dependent deacetylase involved in healthy regulation [42]. Studies show that Klotho deficiency downregulates SIRT1 expression and activity in aortic endothelial and smooth muscle cells and activating SIRT1 with SRT1720 abolishes Klotho deficiency-induced arterial stiffness and hypertension in mice [42]. Exercise training has been shown to improve heart function in rats by activating both sirtuins (SIRT1, SIRT3) and Klotho, suggesting a synergistic relationship [4]. Klotho supports SIRT6 indirectly via stress reduction, suggesting it is a vital teammate in DNA repair [94].
- NAD+ Levels: Klotho likely affects NAD+ indirectly through sirtuins, as sirtuins need NAD+ to function [62]. Studies show restoring NAD+ can protect aged cells, and since Klotho influences sirtuins, it may play a role in maintaining NAD+ levels [115]. Klotho may regulate NAD+ metabolism and influence its availability through its effects on oxidative stress, mitochondrial function, and sirtuin activation [63]. This suggests a synergistic relationship where Klotho indirectly enhances NAD+ function, leading to better cellular repair, longevity, and energy production [64]. There is also evidence showing that NAD+ may upregulate Klotho, primarily through pathways involving sirtuins (SIRT1), oxidative stress reduction, and mitochondrial function [42]. NAD+ is essential for SIRT1 activation, and SIRT1 has been linked to increased Klotho expression [23]. Studies suggest that SIRT1 activation can enhance renal and vascular Klotho levels, potentially extending lifespan and improving metabolic health [111]. The implication is that at least some of the benefits from NAD+ may be tied to Klotho upregulation.
- Stem Cells: Klotho’s impact on telomerase is strongest in stem cells, where it helps maintain their ability to divide and regenerate, potentially offering new ways to treat “aging” related diseases [84]. Studies in stem cells, like adipose-derived stem cells (ADSC), show that Klotho deficiency accelerates aging by impairing telomerase activity, leading to shorter telomeres and reduced proliferation [126]. Klotho deficiency diminished telomerase activity by altering TERF1 and TERT expression, causing impaired differentiation and senescence [126].
- Autophagy: Autophagy maintains cellular homeostasis and is linked to aging processes; its regulation supports Klotho’s role in cellular maintenance [36].
10.6. Klotho: Driver of HLFD
11. Klotho and Reproductive Health, Both Biomarkers for HLFD
11.1. Klotho and Reproduction
11.2. Klotho in Pregnancy and Fetal Development
12. Klotho Levels During the Different Stages of Life and Systemic Regulation
- Fetal Development: Klotho expression is highest, ensuring rapid cellular differentiation, cellular genesis, and repair [66].
- Infancy and Childhood (0–12 years): Elevated Klotho levels maintain immune resilience, cognitive growth, and systemic function [66].
- Adolescence (13–18 years): Klotho reaches peak levels, ensuring peak metabolic function, reproductive health, and systemic balance [74].
- Young Adulthood (18–35 years): Klotho levels plateau into a healthy sustainable state that keeps the system functioning properly through reproductive and child-rearing years [74].
- Midlife (35+ years): When systemic dysregulation occurs, Klotho declines, leading to HLFD and progressive functional failure [76].
- Advanced Age: In well-regulated individuals (e.g., centenarians), Klotho remains higher, better combating HLFD and maintaining function despite chronological aging [136].
13. The Stressor Paradox: Klotho’s Role
| Biomarker | HLFD Indicator | Reference |
|---|---|---|
| Klotho Levels | Plasma Klotho levels below 600 pg/mL indicate early HLFD risk; contrast with optimal 1400–2000 pg/mL | [74] |
| Testosterone | Levels below reproductive equilibrium, correlated with systemic failure | [67] |
| Estrogen | Premature ovarian failure or disrupted menstrual cycle | [123] |
| Vitamin D Metabolism | Dysregulated synthesis & utilization, indicating metabolic instability | [60] |
| Glucose-Insulin Regulation | Insulin resistance and increased risk of diabetes | [135] |
| Inflammatory Markers | Chronic elevation of IL-6 and TNF-α, indicative of immune dysfunction | [41] |
| Neurological Function | Cognitive decline, hippocampal shrinkage, and impaired neuroplasticity | [32] |
| Longevity Approach | Flawed Assumption | Why HLFD Is Superior | Reference |
|---|---|---|---|
| Caloric Restriction | Aging is metabolic wear & tear | HLFD shows an active metabolism drives repair, not just energy intake | [86] |
| Senolytics | Aging is "zombie" cells | HLFD demonstrates healthy cellular turnover maintains senescent function and clearance | [70] |
| Rapamycin & mTOR Inhibition | Aging is hyperactive growth | HLFD calls for restoring a healthy balance, not just slowing decline | [65] |
14. Clinical Implications
15. HLFD as a Medical Diagnosis: Biomarkers and Diagnostic Tools
15.1. Potential Diagnostic Tools for HLFD
- Blood Tests for Klotho Levels: Plasma levels below 600 pg/mL correlate with early HLFD symptoms; ELISA protocols established in Cheema et al. (2022) could standardize this threshold [74].
- Comprehensive Hormone Panels: Assess testosterone, estrogen, and progesterone function to detect dysregulation [15].
- Inflammation Markers: Chronic immune activation (e.g., IL-6, TNF-α) suggests systemic dysregulation [41].
- Cognitive Function Tests: MRI scans showing hippocampal shrinkage may indicate HLFD-linked cognitive decline [32].
16. Finding the Optimal Balance for Longevity and Healthspan
16.1. Why Over-Restoration May Be a Mistake
16.2. What Is the Optimal Level of Klotho for Supercharged Health and Lifespan?
17. Why mRNA Klotho Therapy
17.1. mRNA vs. Recombinant Protein Therapy
17.2. mRNA vs. Gene Therapy
17.3. mRNA Therapy Allows Natural Feedback Regulation
18. For Discussion: HLFD as a Treatable Disease
19. Scientific Implications: New Direction, Better Approaches
19.2. Potential Future Research
- The Final Frontier: Explore microgravity and zero gravity’s effects on Klotho. Could Klotho supplementation support space exploration?
19.3. Proposed Studies
- Cohort Study: Measure Klotho via ELISA in 500 adults (35–65), correlating levels (600 vs. 1400–2000 pg/mL) with HLFD biomarkers (e.g., fertility, inflammation) [74].
- Mouse Trial: mRNA Klotho therapy to sustain the mouse correlate of 1400–2000 pg/mL in humans, assessing lifespan, reproduction, and systemic health vs. controls [61].
19.4. Potential Impact
- Lifespan Extension: Sustaining Klotho at 1400–2000 pg/mL could push human lifespan beyond its accepted limit; if repair outpaces entropy, could we optimize lifespan in the global population to mirror and surpass centenarians? [10].
- Societal Shift: A population with optimal Klotho could reduce mortality and healthcare burdens, it is reducing healthcare costs and redefining human potential [74].
19.5. Challenges and Considerations to be Studied
19.6. Broader Questions
- Could Klotho and other therapies that correctly target HLFD mimic Hydra’s immortality in humans, maintaining cellular function and health? [88]
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