New research suggests a blood-based aging marker may not only predict lifespan, but also respond to intervention.
Aging may leave fingerprints in the bloodstream long before it shows up in the mirror. That is the underlying idea behind a new large-scale study examining glycans, tiny sugar molecules attached to antibodies that quietly shape how the immune system behaves over time. While glycans have been studied for years inside scientific circles, new research is pushing them closer to the center of the longevity conversation.
In what researchers describe as the largest analysis of its kind to date, scientists reviewed data from more than 20,000 individuals across 42 independent studies spanning nearly two decades. Their conclusion: patterns in IgG glycans appear to strongly track biological aging, predict mortality risk and, perhaps most intriguingly, respond to interventions designed to improve healthspan.
The paper, titled The Immunoglobulin G Glycome: A Modifiable Biomarker and Functional Effector of Aging, Disease, and Mortality, was led by Professor Gordan Lauc of GlycanAge and the University of Zagreb, alongside collaborators from the Buck Institute for Research on Aging, King’s College London, the University of Freiburg and more than 20 other institutions worldwide [1].
The body keeps score
Most people think of aging as something visible: wrinkles, gray hair, slower recovery, lower energy. However, researchers increasingly see aging as an immune and inflammatory process happening beneath the surface years earlier.
That is where glycans come in. These sugar molecules attach themselves to antibodies called immunoglobulin G, or IgG, which play a central role in immune defense. Over time, glycan patterns appear to shift alongside chronic inflammation – the low-grade immune overactivation often linked to cardiovascular disease, frailty, cognitive decline and other age-related conditions.
In simple terms, glycans may act a bit like biological “mood rings” for the immune system. When the body is functioning well, glycans tend to signal balance and repair. Under chronic stress or aging, those patterns become more inflammatory.
The study found that these glycan signatures were independently predictive of all-cause mortality, meaning they could potentially serve as a meaningful biological aging marker rather than simply reflecting chronological age. Two people can both be 50 years old on paper while their bodies tell very different stories internally.
Can aging markers actually move backwards?
Perhaps the most closely watched finding in the paper is not that glycans track aging, but that they appear to change in response to intervention.
Researchers evaluated three approaches associated with healthier aging: caloric restriction, hormone replacement therapy and therapeutic plasma exchange (TPE). Of the three, TPE showed the strongest monthly reduction in glycan age.
The study reports that monthly plasma exchange reduced glycan age by roughly 0.4 years per month during longitudinal monitoring.
For a longevity field often criticised for overpromising, the wording here is important. Researchers are not claiming people suddenly became chronologically younger. Instead, biological markers associated with immune aging shifted in a more youthful direction.
That nuance may sound subtle, but it is becoming increasingly important as longevity science matures. The field is slowly moving away from anti-aging slogans and toward measurable physiological changes that can be tracked over time.
“What distinguishes this approach is that therapeutic plasma exchange has been studied in a structured setting, with measurable biological effects,” said Professor Gordan Lauc, Chief Scientific Officer at GlycanAge and Professor of Biochemistry at the University of Zagreb.
“By assessing IgG glycosylation, we can quantify its impact on chronic inflammation and immune ageing, providing an objective framework for evaluating and applying this therapy in clinical practice,” he added.
Why plasma exchange is suddenly attracting attention
Therapeutic plasma exchange is not new medicine masquerading as innovation. The procedure has existed for more than 50 years and is already used in hospitals for autoimmune, neurological and blood-related disorders, including Guillain-Barré syndrome and myasthenia gravis.
The process itself is relatively straightforward: plasma is removed from the blood and replaced, helping clear inflammatory or dysfunctional circulating factors from the body. What is new is its growing role inside longevity medicine.
For years, plasma-based rejuvenation sat uncomfortably between serious science and Silicon Valley fascination, partly fuelled by speculative “young blood” narratives and limited human evidence, but that picture may be starting to change as more structured clinical data emerges.
The new glycan findings build on earlier work from Circulate Health and the Buck Institute for Research on Aging. In a previously published randomized placebo-controlled trial, biweekly TPE sessions combined with intravenous immunoglobulin reduced biological age by an average of 2.6 years across a multi-omics panel.
The glycan analysis now adds another layer of evidence from a completely different biological measurement system.
“Longevity science is entering a new phase – one where we can begin connecting mechanistic insights from the laboratory to measurable outcomes in patients,” said Eric Verdin, co-founder of Circulate and CEO of the Buck Institute for Research on Aging. “Research like this helps move the field toward more rigorous, evidence-based approaches to extending healthspan”.
Bigger shift happening in longevity
Beyond the headlines about plasma exchange or biomarkers, the deeper story may be about credibility. Longevity science is rapidly becoming commercialized, but the sector still struggles with a fundamental problem: how do you objectively measure whether an intervention is truly affecting aging itself?
The researchers argue that glycans may help answer that question because they appear to meet several key standards proposed by the Biomarkers of Aging Consortium. In other words, they are tied to known mechanisms of aging, linked to real-world outcomes and responsive to intervention.
That combination is rare. The field still has a long way to go. Glycans are unlikely to become a magical aging crystal ball overnight, and larger peer-reviewed clinical studies will still be needed, but the direction of travel is becoming harder to ignore.
Longevity medicine is slowly evolving from a space driven by aspiration into one increasingly shaped by measurable biology. And if glycans continue proving reliable, they may become one of the tools that finally helps translate the science of aging into something clinicians can actually monitor…and eventually modify.
Inflammaging in Clinical Practice is a one-day intensive designed for clinicians and longevity experts. The event focuses on providing practical frameworks for assessing immune aging and integrating preventive care into standard practice.
- Date: 20 June 2026
- Location: Hotel Dubrovnik Palace, Croatia
- Registration: Join the event here
Photographs courtesy of GlycanAge
[1] https://www.medrxiv.org/content/10.64898/2026.04.21.26351390v1
