Aging Is Now Measurable — But Recovery Is the Bottleneck

As Nature Aging marked its fifth anniversary, the journal asked many of the field’s most influential scientists a deceptively simple question:

what have we learned about aging,

where are we headed, and

what still stands in the way?

Taken together, the answers form something rare in modern biomedicine: a broad, cross-disciplinary convergence. Not on a miracle therapy or a single pathway—but on a shared reframing of what aging is, what medicine can realistically do about it, and why progress has been slower than headlines suggest.

Below, we summarize the key themes that repeatedly emerged, highlight consensus statements worth quoting, and then place them in dialogue with the Exposure-Related Malnutrition (ERM) framework and the idea of mitochondrial constraint.

1. We Finally Know How to Measure Aging — and That Changes Everything

Across the Q&A, there was near-universal agreement that the biggest advance of the past decade has been the ability to quantify aging itself.

Consensus statement:  Aging has become measurable, not just inferable from disease or mortality.

Epigenetic clocks, proteomic clocks, and longitudinal “pace-of-aging” metrics now allow researchers to:

• Study aging before irreversible disease appears

• Test interventions without waiting decades

• Frame aging as a rate or trajectory, not a static label

This alone has transformed geroscience from a philosophical pursuit into a trial-ready discipline.

Yet many contributors offered an immediate caveat:

Consensus statement:  What we can measure reliably is aging-associated change, not necessarily aging causation.

Clocks are powerful—but they often reflect downstream physiology, not the upstream limits that determine whether recovery is possible.

2. Aging Is Plastic, Regulated — and Hard to Shift Durably

Another strong theme was the rejection of aging as purely random wear and tear.

Consensus statement:  Aging is neither fully stochastic nor fully programmable; it reflects regulated biological processes interacting with environment and history.

This explains why:

• Aging shows deep evolutionary conservation

• Interventions can shift biological age

• Yet effects in humans are often modest and transient

Partial reprogramming and rejuvenation strategies generated both excitement and restraint. Many agreed on the principle of reversibility—but warned against equating short-term molecular shifts with durable functional recovery.

This is where the conversation begins to touch the limits that ERM explicitly addresses.

3. Aging Is Systemic and Uneven — Not One Clock, One Body

One of the clearest points of agreement was that aging does not proceed uniformly.

Consensus statement:  An individual can have a “young” brain and an “old” liver — aging is organ-discordant and system-specific.

Multi-omics and single-cell data now show:

• Different tissues age at different rates

• Organs influence each other through systemic signaling

• Loss of coordination matters as much as local damage

This reframes aging less as isolated failure and more as loss of biological orchestration.

4. Translation Is Failing — Not Because Biology Is Wrong, but Because Humans Are Different

Perhaps the most sobering consensus concerned translation.

Consensus statement:  Mechanisms translate from animals to humans far better than effect sizes do.

Repeated concerns included:

• Unrealistic animal environments

• Neglect of sex-specific aging

• Extreme human heterogeneity (genetic, social, behavioral)

• Short-lived model organisms used to study long-lived species

Many contributors converged on a blunt conclusion:

Consensus statement:  We are still at the beginning of true human geroscience.

5. Prevention and Functional Capacity Are the Real Clinical Prize

Despite disagreements about interventions, there was striking agreement on clinical direction.

Consensus statement:  The greatest impact of aging research will come from prevention, not late-stage disease treatment.

The vision repeatedly articulated was:

• Monitoring aging trajectories early

• Identifying accelerated decline before symptoms

• Preserving function, resilience, and independence

Several compared aging to hypertension: an upstream risk factor that medicine learned to manage long before heart attacks occur.

6. Where ERM and Mitochondrial Constraint Complete the Picture

What the Q&A discusses implicitly—but does not fully integrate—is why aging becomes so difficult to reverse, even when signals say “repair.”

This is where Exposure-Related Malnutrition (ERM) provides a missing mechanistic layer.

ERM frames aging not primarily as damage accumulation, but as a chronic mismatch between energetic demand and recovery capacity. Under sustained stress—psychological, inflammatory, metabolic, environmental—organisms adapt by reallocating energy toward immediate survival. Over time:

• Recovery becomes underfunded

• Repair is postponed, not canceled

• Aging accelerates without obvious deficiency

At the center of this process lies mitochondrial constraint.

Even when:

• Nutrients are available

• Hormonal signals remain intact

• “Longevity pathways” are appropriately activated

Recovery fails if mitochondrial throughput, redox flexibility, and NAD⁺ availability are insufficient to execute ATP-dependent repair.

In ERM terms, this explains a key paradox highlighted throughout the Q&A:

Why aging appears modifiable in principle, but stubborn in practice.

Clocks can move. Signals can shift. But recovery is conditional—and mitochondria are the rate-limiting infrastructure.

7. From Measuring Aging to Restoring Recovery

The Nature Aging Q&A makes one thing clear: the field is moving from measuring decline to attempting restoration.

ERM adds a necessary constraint to that ambition:

• Recovery is not a switch

• Rejuvenation is not free

• Plasticity is bounded by bioenergetic capacity

This reframes aging intervention away from “turning pathways on” and toward restoring the energetic conditions under which repair is possible.

A Closing Thought

The most honest message in the Q&A may be this:

Consensus statement:  We know far more about how aging is measured than how recovery is funded.

Bridging that gap—between signaling and execution, between clocks and capacity—may determine whether geroscience becomes a transformative medical discipline or another cycle of overpromised potential.

ERM does not contradict the field’s optimism.

It simply reminds us that biology always balances its books.

And recovery, unlike stress, is never guaranteed.

Aman, Y., Kriebs, A., Ren, Q., Walters, H., & Thuault, S. (2026). Past, present and future perspectives on the science of aging. Nature Aging, 6(1), 6–22. https://doi.org/10.1038/s43587-025-01046-2