Photo by Tiago Muraro on Unsplash
Human development throughout life can be seen as a gradual sequence of changes — from an egg cell to the grave. It seems logical to assume that the entire organism matures and ages simultaneously, following a smooth progression. However, scientists have discovered that these processes unfold according to a different, less obvious logic.
AGING FOLLOWS ITS OWN RULES
Aging is a highly complex process — far more intricate than many assume. People tend to associate it primarily with an increasing risk of various diseases. However, research on the biology of aging conducted at Oxford provides deeper insights into how and what kinds of changes actually occur in our bodies. The more we understand, the greater our ability to influence and control this process. With this goal in mind, scientists formed a study group of 108 adults aged 25 to 70.
Every two months, over several years, biological samples were collected from the participants. By analyzing these samples, researchers tracked various types of biomolecules — RNA, proteins, lipids, and taxonomic compositions of the gut, skin, nasal, and oral microbiomes. In total, they examined 135,239 biological characteristics, generating over 246 billion data points.
The collected data was analyzed to identify patterns in these changes. Surprisingly, the risk of Alzheimer’s, cardiovascular, and other diseases does not simply increase «on its own» over time. In other words, aging biomarkers revealed that this process is neither gradual nor uniform.
Instead, risks spike only after a specific age and at distinct stages.
THE MATHEMATICS OF AGING: 44 AND 60 — THE DANGEROUS AGES
Have you ever woken up one morning, looked in the mirror, and suddenly felt like you had aged overnight? If so, don’t think it was just your imagination.
According to geneticist Michael Snyder from Stanford University, we don’t simply change gradually over time — at certain moments, we undergo dramatic shifts. By studying molecular changes associated with aging, scientists have identified two major turning points in human development. One typically occurs around age 44, and the other around age 60. In fact, 81% of study participants experienced significant biological changes at one or both of these stages.
The nature of these changes varied slightly. The first peak, occurring around 44, was associated with shifts in molecules linked to lipid metabolism, caffeine, and alcohol processing, as well as cardiovascular diseases, skin dysfunction, and muscle decline.
The second peak, appearing around 60, was connected to carbohydrate and caffeine metabolism, cardiovascular issues, skin and muscle problems, immune regulation, and kidney function.
DIFFERENT ORGANS AGE DIFFERENTLY
Interestingly, these aging shifts are not unique to humans. Previous studies have identified nonlinear molecular changes in fruit flies, mice, and zebrafish. This suggests that a staged aging process may be a universal phenomenon across living organisms, even though the duration and number of stages may vary between species.
Future research may provide deeper insights into this phenomenon by examining a broader range of subjects. However, it’s not just the human body as a whole that ages unevenly — our individual organs also age at different rates and in various ways.
This idea was first proposed by researchers from the National University of Singapore, who studied protein molecules in the blood of 480 individuals aged 20 to 45. By measuring a total of 403 biological markers in each participant, they classified these biomarkers into nine categories.
This allowed them to determine the biological age of various organs, including the kidneys, liver, gut microbiome, cardiovascular system, immune system, metabolic system, and reproductive hormone system. The next step was to compare biological age with chronological age…
DIFFERENT AGES, DIFFERENT HABITS!
The study found that the strongest correlation with chronological age was observed in the cardiovascular system, whereas the gut microbiome showed the weakest connection. The greatest variations in biological age among individuals were noted in the liver and the reproductive hormone system.
This confirmed that different parts of the body have different biological ages. For example, the lungs and kidneys experience a surge in aging around the age of 20 — decades ahead of other organs, such as the uterus. The rate of aging is influenced by the condition of organ cells, which varies depending on genetic factors and lifestyle.
This means that certain healthy habits become especially important at different stages of life. By understanding this, we gain the ability to adjust our lifestyle and better regulate the aging process.
Monitoring the biological age of specific organs could also help predict the risk of various diseases, such as diabetes or non-alcoholic fatty liver disease.
Original research:
- Your organs may be ageing at different rates
- Most comprehensive picture yet of how organs age at different rates
- Nonlinear dynamics of multi-omics profiles during human aging
- Distinct biological ages of organs and systems identified from a multi-omics study
