The research draws on the Gothenburg H70 Birth Cohort Study, one of the longest-running population studies of ageing in the world. In 2014 to 2016, researchers comprehensively examined 70-year-olds born in 1944 who were living in Gothenburg, achieving a 72 percent response rate. Participants underwent extensive interviews and clinical assessments covering education, income, childhood family economic circumstances, mental health, cardiovascular disease, anthropometry, and laboratory measures, and they provided blood samples for genotyping. A follow-up examination was conducted five to eight years later, with a mean follow-up of roughly six years and a response rate of 77.6 percent among survivors. After excluding participants with missing parental data and those whose parents died before age 41, likely from causes unrelated to biological ageing such as accidents, the final baseline sample comprised 1,126 individuals, 523 men and 603 women.

The researchers classified parental longevity, or PL, into three groups. Participants were considered to have high parental longevity if both parents survived to age 85, which applied to 17.2 percent of the sample; medium parental longevity if one parent reached 85, applying to 43.3 percent; and low parental longevity if neither parent did, applying to 39.4 percent. The age-85 threshold was chosen deliberately: the participants’ parents were born around 1920, when cohort life expectancy was only about 74 years, so reaching 85 represented genuinely exceptional survival for that generation. Alongside this family-history measure, the team constructed two polygenic longevity scores, or PGLSs, using genome-wide association summary statistics from a large international meta-analysis of longevity genes, combined with a Bayesian shrinkage method and a European ancestry reference panel. One score included variants in the APOE locus, a gene region strongly tied to age-related disease and mortality, while the other excluded it.

At baseline, both higher parental longevity and higher polygenic scores were associated with more favourable social circumstances. People with long-lived parents, and people with higher genetic longevity scores, had spent longer in education, reported better childhood family economic conditions, and enjoyed higher current household income. Both measures were also linked to vascular health: high parental longevity and higher scores on the APOE-inclusive polygenic score were associated with less hypertension, and higher polygenic scores were inversely related to myocardial infarction, a finding the authors report as novel. But the two measures diverged sharply beyond that point, and the divergence is where the study becomes genuinely provocative.

Parental longevity, unlike the genetic scores, was associated with a broad constellation of biological advantages. Participants with high parental longevity had better scores on the Mini-Mental State Examination, higher levels of total cholesterol, HDL cholesterol and LDL cholesterol, lower body mass index, lower homocysteine, and lower levels of the inflammatory markers interleukin-6 and C-reactive protein. They were also less likely to be current smokers. Participants with even one long-lived parent showed better cognition, higher cholesterol, lower homocysteine and less smoking than those with two short-lived parents. The polygenic scores, by contrast, captured mainly the socioeconomic and cardiovascular factors and little else. Strikingly, the two measures showed no statistical association with each other at all, whether parental longevity was analysed as groups, as the mean of both parents’ ages, or as mothers’ and fathers’ ages separately.

Some of these findings challenge conventional assumptions. The higher total cholesterol and LDL cholesterol among offspring of long-lived parents may seem paradoxical, but they echo previous research, including studies suggesting that rising cholesterol in late life is associated with reduced dementia risk and lower mortality in older adults. Cholesterol is a precursor to steroid hormones essential for metabolism and immune function, and the authors caution that the so-called cholesterol paradox in late life should be interpreted carefully, noting that lipid-lowering therapy did not appear to explain the association and that frailty was rare in this relatively young-old population. Lower homocysteine among those with long-lived parents is also notable, since elevated homocysteine is linked to folate and vitamin B deficiency, endothelial dysfunction, atherosclerosis, cardiovascular events, and dementia.

Perhaps the most forward-looking result emerged at follow-up. Plasma phosphorylated-tau 217, or pTau217, is one of the most accurate blood biomarkers currently available for Alzheimer’s disease pathology, and its levels are known to rise steeply with age. In the longitudinal analyses, participants with high parental longevity showed significantly less increase in pTau217 over the six years than those whose parents had both died before 85. This suggests that Alzheimer’s pathology may establish itself later, or accumulate more slowly, in people with long-lived parents, potentially delaying the onset of dementia. Consistent with this, the high-parental-longevity group also had higher baseline MMSE scores. No such longitudinal associations were observed for the polygenic scores, and neither measure was associated with plasma neurofilament light, another age-sensitive neurodegeneration marker.

The authors are careful about causality. Lower interleukin-6 and C-reactive protein in offspring of long-lived parents may reflect healthier lifestyles and better overall health rather than a direct determinant of longevity, although low-grade inflammation, sometimes called inflammaging, is considered a central driver of accelerated ageing, dementia, cardiovascular disease and mortality. Sex also mattered: several associations, including those involving C-reactive protein, neurofilament light, creatinine and triglycerides, were significant only in women. The team also acknowledges limitations, including self-reported parental ages, possible selective survival bias, a predominantly white and age-homogeneous sample, and the smaller follow-up cohort, and they report both uncorrected and false-discovery-rate-corrected statistics, noting that some findings, including those on inflammatory markers and pTau217, did not survive multiple-comparison correction.

Nevertheless, the overall pattern is coherent and biologically plausible. Polygenic longevity scores, in their current form, appear to capture only a narrow slice of the biology of ageing, likely because longevity’s genetic architecture is highly heterogeneous and heavily environment-dependent. Parental longevity, by contrast, seems to summarise everything at once: inherited genetics, shared early environment, transgenerational social advantage, and accumulated lifestyle influences. The authors conclude that asking about parental lifespan could serve as a simple, inexpensive proxy for biological ageing, suitable for routine health assessments of older adults to flag individuals who might benefit from preventive screening for hypertension, cognitive decline, inflammation and emerging Alzheimer’s pathology. In an era of billion-dollar biomarker pipelines, the humble family history may still be one of medicine’s most underrated diagnostic instruments.

Subject of Research: Parental longevity and polygenic longevity scores in relation to ageing-related social, cardiovascular, inflammatory and neurodegenerative factors in 70-year-olds

Article Title: Parental longevity and polygenic longevity scores in relation to ageing-related factors in a population of 70-year-olds followed over six years: The Gothenburg H70 Birth Cohort Study

Article References: Seidu, N. M., Rydén, L., Skoog, J., Samuelsson, J., Kern, S., Waern, M., Zetterberg, H., Holstege, H., Erhag, H. F., Westman, E., & Skoog, I. (2026). Parental longevity and polygenic longevity scores in relation to ageing-related factors in a population of 70-year-olds followed over six years: The Gothenburg H70 Birth Cohort Study. GeroScience. https://doi.org/10.1007/s11357-026-02501-7

Image Credits: AI Generated

DOI: 10.1007/s11357-026-02501-7

Keywords: parental longevity, polygenic longevity score, ageing, GeroScience, APOE, pTau217, Alzheimer's disease, inflammation, cholesterol, cardiovascular risk, socioeconomic status, H70 cohort

Epigenetic clocks have revolutionized the study of aging by providing a molecular window into how lifestyle, environmental stressors, and societal conditions condition human health trajectories. The research team highlights the complexity stemming from the existence of multiple generations of epigenetic clocks, each differing in sensitivity and specificity. First-generation clocks primarily estimate chronological age with reasonable accuracy but show limited responsiveness to external influences. In contrast, second- and third-generation clocks, designed respectively to capture health-related aging processes and the dynamic pace at which aging unfolds, demonstrate a stronger, more insightful correlation with social determinants such as poverty, systemic racism, and other dimensions of social disadvantage.

The study’s findings decisively confirm that social adversity accelerates biological aging, with the most sensitive measures being the newer epigenetic clocks. These advanced tools reveal that individuals exposed to lower socioeconomic status not only biologically age faster but also experience more rapid declines in health and longevity. Such insights underscore the biological embedding of social experience — where the inequities encoded in society manifest physically at the cellular and molecular levels. This revelation provides a mechanistic explanation for well-documented disparities in health outcomes between economically privileged populations and their marginalized counterparts.

Importantly, the research uncovers that the effects of social disadvantage on biological aging are detectable early in life. Children raised in socioeconomically deprived environments already exhibit epigenetic signs of accelerated aging compared to their more affluent peers. The implications of this finding are profound, as it suggests that adverse social environments exert a biological imprint from a young age, setting individuals on a trajectory of premature aging that may lead to greater vulnerability to chronic diseases and reduced lifespan.

Further, this scientific endeavor confirms that the biological ramifications of early life socioeconomic adversity endure well into adulthood. Adults who experienced disadvantaged conditions during childhood continue to exhibit exacerbated biological aging decades later, independent of their social environment in adulthood. This finding suggests a long-lasting, possibly irreversible, biological embedding of early social experiences, emphasizing the critical importance of interventions during childhood to mitigate lifelong health disparities.

The analysis also shines a light on racial and ethnic health disparities in the United States. The data confirm that Black participants show significantly accelerated biological aging compared to White participants when assessed by second- and third-generation epigenetic clocks. Latinx participants, similarly, show accelerated aging but to a slightly lesser degree. These results provide molecular evidence for the biological consequences of systemic racism and ethnic marginalization, substantiating that social determinants extend beyond economic factors and permeate racial inequalities in health.

This research holds transformative potential for health science and policy, offering not just diagnostic tools but also avenues to evaluate and guide interventions aimed at reducing social inequities. Epigenetic clocks could become pivotal biomarkers to assess the effectiveness of programs designed to alleviate poverty, improve education, combat discrimination, and enhance overall social welfare. By quantifying the biological benefits of such programs, these clocks can bridge the gap between social policy and biological outcomes, promoting targeted strategies to slow accelerated aging and improve healthspan.

Technically, the meta-analysis employed sophisticated methods to harmonize disparate data sources, encompassing over a thousand quantified effect sizes from studies with participants ranging from newborns to nonagenarians. This methodological rigor enables robust conclusions about the consistency and strength of relationships between social determinants and epigenetic measures of aging, overcoming previous limitations due to heterogeneity in study designs, populations, and epigenetic clock metrics.

Moreover, the elucidation of which epigenetic clocks are most informative for social health research helps resolve confusion plaguing the field. First-generation clocks, although useful for age prediction, are insufficiently sensitive to discern variations in biological aging driven by social stressors. The newer generations that integrate markers related to inflammation, cellular senescence, and metabolic dysfunction correspond more directly to the multifaceted physiological processes involved in aging and disease susceptibility influenced by one’s social environment.

The publication of these findings in the prestigious journal Nature Human Behaviour marks a major milestone, highlighting the integration of social science and molecular biology in unraveling the fabric of human health inequities. The study’s insights propel a compelling narrative that the aging process itself is socially stratified, mediated by both lived experiences and molecular changes, which cumulatively shape health trajectories from cradle to grave.

Ultimately, this research not only advances scientific understanding but also fundamentally challenges us as a society to acknowledge and address the biological toll exacted by social inequality. By scientifically validating the profound imprint of disadvantage on the human epigenome, it urges concerted efforts across disciplines to foster equitable environments that promote both longevity and quality of life.

Subject of Research: People

Article Title: Social determinants of health and epigenetic clocks: a systematic review and meta-analysis of 140 studies

News Publication Date: 12-Jun-2026

Web References: http://dx.doi.org/10.1038/s41562-026-02477-6

Image Credits: MPI for Human Development

Keywords: social inequality, epigenetic clocks, biological aging, socioeconomic status, racial disparities, meta-analysis, health disparities, DNA methylation, aging biomarkers

Neurofilament light chain serves as a critical structural component of neurons, forming part of the cytoskeletal network within axons. Under conditions of neuronal stress, damage, or degeneration—common in various neurological disorders and aging—NfL is released into the extracellular space and eventually enters the bloodstream. The detection of NfL in plasma or serum has emerged as a sensitive technique for evaluating neuronal integrity and neurodegeneration. In the context of human health, elevated NfL levels appear in diseases such as Alzheimer’s disease and amyotrophic lateral sclerosis (ALS), while gradually rising baseline levels correspond to the normal aging process.

Exploring this phenomenon beyond human subjects, Prof. Mathias Jucker, a research group leader at DZNE and HIH, and his team have documented that NfL plasma concentrations exhibit a remarkably similar pattern in various animal species, including commonly domesticated and laboratory animals. By examining aged cohorts of mice, cats, dogs, and horses, they established consistent age-associated increases in blood NfL levels. These findings raise the possibility that NfL functions as a universal biomarker of neurological aging, conserved across mammalian species despite differences in life spans and physiology.

Further deepening the significance of NfL’s utility, the team carried out longitudinal observations in a cohort of 44 elderly mice, monitoring their blood NfL levels systematically over a four-month period. Strikingly, individuals exhibiting a slower rate of increase in NfL concentrations tended to enjoy longer lifespans, whereas those with rapid elevations faced diminished survival. This correlation between NfL dynamics and mortality risk mirrors similar epidemiological data reported in aging human populations, where NfL levels predict all-cause mortality, suggesting that the trajectory of neurofilament accumulation is not merely a biomarker but holds predictive power over biological aging and viability.

The study extended its scale by sampling 53 diverse animal species, ranging from other mammals such as rabbits, lions, and monkeys to reptiles and birds, in collaboration with institutions such as the Stuttgart Zoo and the Vetsuisse Faculty at the University of Zurich. While NfL protein was consistently detectable in the blood of all mammals studied, it appeared less frequently in non-mammalian species. For example, some reptiles and birds like crocodiles and parrots showed detectable NfL, although differences in the protein’s amino acid sequence across taxa may reduce assay sensitivity, necessitating customized detection methods in future research.

These cross-species insights reveal the translational potential of NfL measurement, originally developed in dementia and neurological disease research, into the realm of veterinary diagnostics. Neurologically driven aging and health decline likely share conserved pathological mechanisms reflected by NfL release, making this biomarker an invaluable tool for assessing neurological health status, biological age, and potential lifespan in animals. This could revolutionize animal care, enabling early identification of neurodegenerative conditions and improving life expectancy predictions across a vast taxonomic spectrum.

The technical backbone of this research hinges on the use of highly sensitive immunoassays capable of quantifying minute concentrations of NfL in blood samples. These assays detect epitopes on the protein’s structure, which, given evolutionary variations, may sometimes limit detection in certain species. Overcoming these limitations may involve developing species-specific antibodies or employing mass spectrometry-based methods to broaden the spectrum of identifiable NfL variants. The meticulous analytical rigor in this research ensures reliable quantification, essential for establishing meaningful correlations between NfL levels and physiological aging metrics.

Neurodegenerative diseases like Alzheimer’s and ALS remain global health challenges, their pathological mechanisms intricately tied to neurofilament disruption. Biomedical research into biomarkers such as NfL provides insights not only for human clinical purposes but also offers blueprints for comparative aging studies. The demonstration that similar neurodegenerative biomarkers apply to animals closes gaps between human medicine and veterinary science, fostering integrative approaches to aging and neurological disease management.

Experts underscore that understanding the neurobiological aging process at the molecular and cellular level contributes to broader strategies for healthy aging interventions. Biomarkers like NfL enable objective measurement of neuronal damage over time, a critical step in monitoring disease progression or the effectiveness of therapeutic interventions. The identification of blood-based biomarkers that function consistently across species introduces potent new tools for research and applied veterinary medicine, with implications for enhancing animal welfare and extending healthy life spans.

In addition, the ability to estimate life expectancy noninvasively through blood NfL measurement offers valuable applications in conservation biology and zoological management. For endangered species or animals in captivity, such accurate biomarkers facilitate longitudinal health monitoring, guiding care decisions and breeding programs. This innovation also responds to a pressing need within veterinary diagnostics for objective, easily accessible indicators of aging and neurodegeneration beyond symptomatic observation.

Moving forward, integrating NfL assessments into routine veterinary practice could dramatically alter paradigms of animal healthcare. Regular blood tests measuring NfL could become standard wellness checks, enabling preemptive interventions before the emergence of overt neurological symptoms. Alongside other clinical markers and imaging studies, NfL quantification builds a comprehensive picture of neurological health status, empowering veterinarians and animal caretakers with precise evaluative tools.

This pioneering research heralds a new era of cross-disciplinary collaboration, where methodologies from human dementia research inform and enrich animal health sciences. The DZNE and HIH teams exemplify this translational research ethos, advancing understanding of aging as a shared biological phenomenon. As the scientific community continues to decode the complexities of neurodegeneration and biological timekeeping, biomarkers like neurofilament light chain will likely become cornerstones of both human and veterinary medicine.

Ultimately, the recognition that neurofilament light chain is a conserved, measurable biomarker presenting consistent age-related changes across mammals ushers in transformative prospects. From basic research on neuronal integrity to practical applications in veterinary health and lifespan prediction, NfL holds the promise to bridge species divides, illuminating shared biological aging pathways and fostering innovations that benefit patients and animals alike.

Subject of Research: Animals
Article Title: Neurofilament light chain may serve as a cross-species blood biomarker to assess aging and predict mortality
News Publication Date: 19-Feb-2026
Web References: http://dx.doi.org/10.1371/journal.pbio.3003606
Keywords: Biomarkers, Neuroscience, Neurodegenerative diseases, Life expectancy, Veterinary medicine