A recent study found that 81% of people undergo dramatic changes in the body at the ages of 44 and 60. — MATTHIAS ZOMER/Pexels
We know that the human body can regenerate many of its cells, especially those worn by wear-and-tear, and those damaged by external factors and the environment. Our skin, for example, is continually replenished otherwise every tiny cut or injury will still be visible. Our blood is continuously renewed, to ensure that red blood cells are in the best possible condition for transporting oxygen efficiently to the rest of the body. And so on.
So, why do we age? It is simplistic to suggest that our bodies are somehow getting “old” and less able to renew themselves, although it is certain this is what is happening. However, what triggers the decline from a young body capable of continuous rapid growth and regeneration to an “older” and less efficient body over time is an interesting and very curious subject.
Gerontology
Gerontology is the scientific study of ageing, encompassing social, cultural, psychological, cognitive, and biological aspects of growing older. The term was coined by a Russian-French protozoologist called Ilya Ilyich Mechnikov in 1903 and is simply Greek for “study of old man.” Apart from the evident biological and cognitive aspects, gerontology has many angles and can involve profound studies into psychological, social, cultural, and economic issues.
However, gerontological studies have their limitations, even though they may be very good at diagnosing age-related symptoms and perhaps even the root causes of some of the symptoms. At least, such studies have presented a view into the ageing processes within the human body and as a result, have developed remedies and treatments for a range of ailments of the elderly.
Yet, there is no cure for getting old. At best, one can choose to either grow old gracefully in relatively good health or tolerate the marginal decade of life with the help of medications and constant palliative care. For more about the marginal decade, please refer to this earlier column titled ‘The Marginal Decade’.
This column today will not address the issues of gerontology, but instead, it will explore a new fascinating insight into how humans age biologically. A recent research paper published in August 2024 offers evidence that humans do not grow old at a steady pace. Instead, our bodies deteriorate alarmingly at two uncannily specific age points, thereby increasing susceptibility to more maladies and diseases from these two age points onwards.
It might be a good idea to adopt a healthier diet around the ages of 44 and 60 to hinder the effects of ageing. — JANE TRANGDOAN/Pexels
Knowing about these two age points may be helpful for people to adjust their diets and lifestyles to help mitigate the negative aspects of sudden, accelerated biological ageing. This is also because biological age is strongly correlated with the onset of various diseases – humans simply tend to get sicker quicker and more often with age, and therefore it helps to know more about the human ageing processes.
Multi-omics
To understand how the research paper arrived at such a conclusion, it would be helpful to know a little about multi-omics.
Multi-omics refers to a modern integrated approach in biological research that combines data from multiple omics technologies to offer a more comprehensive understanding of biological processes and systems.
This approach provides a comprehensive view of cellular and organ function by analysing different types of biological markers and molecules to derive the volumes of information needed for correlations and related inferences.
Multi-omics is a highly complex field as it involves studying the detailed and complicated integration of data from various ‘omes’, such as the:
• Genome: The complete set of genes and genetic material of a human
• Transcriptome: All the DNA/RNA genetic transcripts produced by the genome during cell reproduction
• Proteome: The entire set of proteins expressed by the cells of human organs
• Epigenome: Factors affecting DNA and associated proteins during gene expression
• Metabolome: The types and ranges of small molecules in human biological systems; eg, amino acids, vitamins, fatty acids, environmental contaminants, food additives, etc
• Microbiome: The collective genomes of the flora of microorganisms in various human environments, such as the gut and the skin.
The research was a collaboration by university scientists from Singapore and the United States and was based on regularly profiling the above “omes” of 108 Americans living in California between the ages of 25 and 75 over a period of years. The research paper was a complex analysis of the changes in the profiles of the study subjects as they aged.
Biological ageing
The intent was to track the biological ages of people, in particular the changes that occur in the body over a lifetime, affecting cells, proteins, microbiomes, and genetic activity. This is different from the chronological age that people celebrate each year on their birthdays.
After measuring the status of more than 11,000 molecules in the adult body over time, the study found that 81% of them undergo dramatic changes at the ages of around 44 and 60.
In particular, the dysregulation of skin and muscle stability was found to be increased at these two specific ages. Additionally, the sudden wide-ranging changes to human multi-omics profiles may be significant because it is another plausible explanation for the reason why the risk of cardiovascular events in the USA increases to approximately 6.5% for people aged around the mid-40s and more, rising sharply to 19.8% from age 60 onwards.
Blood sugar levels also tend to peak at these two age points, along with changes to the metabolic pathways which produce unsaturated fatty acids (which help to lower cholesterol levels). Therefore, there may be a heightened risk of developing type two diabetes at these age points. The efficiency of the human immune system also begins to decline rapidly at age 60.
The capacity to metabolise caffeine deteriorates at age 40 and again at 60. — KETUT SUBIYANTO/Pexels
There are other mini waves of multi-omics degeneration, around the ages of 45 and 65, mainly reflecting changes to the proteome. Transcriptomic issues appear mostly between the ages of 50 and 56, and DNA repair capabilities decline during that interval, after which it stabilises until the age of 75 (which is the age limit of the study).
Changes to the skin and gut microbiomes begin a little earlier, at age 43, while most changes to the mouth/oral microbiome happen at age 41. The nasal microbiome is more affected at age 46.
Curiously, the capacity to metabolise caffeine and alcohol undergoes a notable deterioration around the age of 40, and again at around 60years of age. This is certainly true for me as I now cannot drink my usual two bottles of claret a day, and often I do not even feel the urge to drink any alcohol at all, sometimes for days.
So, for reasons yet unknown, it appears the human descent into old age is not a smooth linear decline, but a bumpy downward ride with two major descents and several mini jolts along the way.
From a dietary perspective, it may be worth considering the idea of adopting better eating habits, notably around the ages of 44 and 60. The human body appears to be undergoing significant internal structural changes (especially at the genetic, metabolomic, and microbiomics levels) at those ages and it is probably advisable to reduce the intake of foods and cut out other lifestyle activities (such as smoking and excessive alcohol consumption) which may provoke inflammation, cancers, and/or metabolic syndrome.
As mentioned earlier, there is no cure for getting old, and it may be prudent not to exacerbate the process any more than necessary, especially during periods when the body appears to be particularly vulnerable.
Interesting as this multi-omics study is, one also needs to know that it was based on only 108 Americans with a range of various ethnicities. It is far from certain if the same ageing peculiarities apply at the same age points for other countries. There is also zero information about the jobs and lifestyles of the group of people studied. And there were no statistics about the dietary aspects of the subjects, and therefore the ageing impacts for vegans, vegetarians, pescatarians, etc, were not reviewed.
Apart from the study’s limitations, it is still noteworthy to understand that the human body apparently becomes more frail and more susceptible to maladies and diseases rather more suddenly and widely than one would expect. From the multi-omics viewpoint, the deterioration begins rather abruptly at around the age of 44, with another somewhat precipitous decline at age 60.
So at least one now has a better idea why the skin and muscles seem to lose their tones the most at these ages. However, the research indicates there are other invisible but no less dramatic changes within the body which can have profound effects on long term well-being.
The views expressed here are entirely the writer’s own.
