Research Uncovers a Surprising Cellular Ageing Paradox That Could Change How We Understand Ageing

Does the body's natural cellular recycling system really slow down with age? A new study challenges this longstanding belief, suggesting that cellular recycling may increase, decrease, or remain unchanged depending on cell type, biological sex, and age.

Published in the journal Aging Cell on September 27, 2026, the study conducted by researchers at Sanford Burnham Prebys Medical Discovery Institute investigated how autophagy, the body's natural process of removing damaged proteins and cellular waste, changes during aging.

Autophagy plays an essential role in maintaining cellular health by breaking down damaged components and recycling them into reusable materials. Disruptions in this process have been associated with several age-related conditions, including cancer, cardiovascular disease, diabetes and neurodegenerative disorders.

Researchers collected blood and skin samples from healthy volunteers aged 23 to 72 years. Some skin cells were converted into induced neurons, allowing the team to examine autophagy across three different cell types.

The findings revealed that cellular recycling did not consistently decline with age. In male skin cells, autophagy activity decreased, while female skin cells maintained relatively stable activity. Interestingly, induced neurons derived from women showed increased autophagy with advancing age.

Among participants aged 70 and older, higher autophagy activity was unexpectedly associated with poorer physical functioning. Increased recycling activity was linked to lower aerobic fitness, higher body mass index, reduced grip strength and changes in metabolic health, depending on cell type.

Researchers also conducted a small pilot study involving five adults aged 77 to 88 years who participated in a 12-week gentle exercise programme.

The preliminary findings suggested that physical activity may help regulate autophagy in blood cells towards levels observed in younger adults, alongside improvements in physical performance.

However, researchers cautioned that the exercise findings were based on a very small sample and require confirmation in larger studies.

REFERENCE: Tatiana M. Moreno, et al.; Autophagy Flux Is Remodeled Sex‐ and Cell Type‐Specifically During Human Aging, and Is Linked to Reduced Physical Function in Older Adults. Aging Cell, 2026; 25 (10) DOI: 10.1111/acel.70734