Further research has been done on biological ageing. It shows that different systems in the body age at different rates. This varies by individual and offers treatment ideas.

This is the World Health Organization definition of ageing. The damage to cells and tissues are permanent and thus cumulate. Small deteriorations build up until the system cannot cope anymore.

Biological Age.

There is a growing disconnect between our chronological and our biological age. Our bodies do not count the number of birthdays we have had. Multiple longitudinal studies have demonstrated this. These take measures of the function of the body at regular intervals. Researchers can then see the decline.

One study measured metabolic, cardiovascular, inflammatory, kidney, liver, and lung function over many years. They combined these measures to create an index of biological age. Using the longitudinal sample they could compare different cohorts. They looked at two groups born twenty years apart. They could look at the functioning of the body at different ages in both cohorts or generations. The younger generation performed better at all ages. They comparing the youngest age group (20-39) twenty years apart. They found a 1.27 year improvement. A twenty-year-old would perform at the level of a 18.73 in the earlier generation. The impact grew with age. For the 60-79 age group the younger generation were performing at a level 4.29 years better. A 65 year old would have a biological age closer to a 60-year-old in the previous generation.

Different Ways of Ageing

A recent article in the New Scientist described how this idea had been pushed further. With more data and more sophisticated analysis it became clear that we do not age in the same way as one or another. In fact, they had 18,393 data points on each of their subjects each quarter. They found over six hundred molecules, genes and microbial species that changed as their subjects aged. Many were already known to show ageing. Others were completely new biomarkers. They realized that these biomarkers were associated with one of four distinct organs or systems. These were the kidneys; liver; immune system and general metabolism.

It turned out that these different systems in the body can age at different rates. All systems decline with age it is just that one or two will “lead the way”. What was more interesting was that the “leaders” varied across individuals. The researchers looked at the patterns and found four major groups of people. They called these “ageotypes”. For example, an immune ageotype individual has an immune system with a biological age older than their other three systems. They kidneys of a “kidney ageotype” are ageing faster than the other systems.

From an ageing point of view these systems do not operate independently. A problem with one system can cause problems with another in the future. They can drag each other down. Slowing down the system that is ageing the fastest can benefit all systems. This will slow overall ageing.

Customizing Treatment for Ageing.

The ageotypes mean that different people need different anti-ageing strategies. As a simple example, a liver ageotype has a liver system that is ageing faster than the other systems in their body. A reduction in alcohol intake will improve liver function. An ageotype whose general metabolism is the problem can adopt a different approach. Weight loss and exercise will both benefit the overall metabolism. Kidneys benefit from an increased water intake.

There is a lot of research that needs to be done to determine the best way to tackle individuals with a particular “leading” ageotype. Research also is pressing ahead to refine the ageotypes. Other teams have suggested that there are other types than the basic four. The combination of longitudinal views and sophisticated data collection will push the boundaries. The value of the longitudinal approach is that they can track cause and effect over time. Those leading ageotypes are linked with disease. Individuals with a liver system older that the rest of the body are more likely to then get liver disease.

Those same studies showed those interlinkage between the systems. An ageing cardiovascular system can subsequently drag down brain age. Cardiovascular ageing also drags down general metabolism.

Individual level diagnosis is also some way away. We are not all going to provide over 18,000 data points. Some simple tests are already available. Standard blood tests can be used to diagnose some things. The can measure inflammation and liver and kidney function. Doctors and researchers can only speculate about the causes of the different ageotypes. Why would I have a liver system that is ageing faster than the other systems in my body. There will be a genetic component. The environment in which I live, and my lifestyle are thought to have an impact. So too will illness in my earlier years. There are lots of questions still to be answered.