From time to time we receive the news of the birthday of a centennial person and, at least, we outlined a tender smile when observing the good physical and mental state that usually shows. But, in addition, we start to ponder the possibility of reaching that age.
Of course, we Spaniards are happy to know that life expectancy in our country is 83 years. One of the largest in the world, and only behind Andorra and Japan. Turning a century, and exceeding that age, is something else. But it does happen, and it is mainly due to lifestyle habits, although certain genetic factors are also involved.
There are heritability studies that estimate that reaching beyond 100 years depends on a third of our genes. The remaining two-thirds are due to how we live, which in part also influences the activity of our genome through so-called epigenetic variations.
The key to living 105 years may be in our genes
Science does not stop surprising us, and this time it does so through a recently published work that shows what is different, at the level of the genetic code, in people aged 105 years or older when compared to healthy individuals of 68 year old.
Well, using high-resolution genome sequencing techniques, five genetic mutations have been detected in the DNA of the centennial group. These are mutations that mainly affect two genes (STK17A and COA1) involved in how cells repair damaged DNA and in the processes of oxidation and cellular respiration. It was already known that among the mechanisms associated with longevity are DNA repair capacity and oxidative stress processes. But this study presents which specific mutations are related to longevity.
Biological age and chronological age
We all know people who, at the same age, look older or younger, depending on the case. And it is that biological age is not the same as chronological age.
Biological age could be defined as the best possible estimator that allows predicting the state of health and life expectancy of a person. Chronological age is simply the time that elapses since birth.
Today, there is no single molecule or physiological parameter that, as a biomarker, can unequivocally identify biological age. Aging occurs as a complex cumulative effect in which multiple and different molecular, physiological and cognitive processes are altered. Furthermore, all these processes take place at different levels; In other words, our cells, tissues, organs and systems are altered, and not all in the same way or at the same time.
Thus, getting to estimate biological age requires a complex approach that allows integrating and drawing conclusions from the multitude of data that can be obtained today from the analysis of all the processes that are affected.
Probably the most popular and well-founded procedure to detect biological age is the so-called “DNA methylation aging clock” or “epigenetic clock”, from which there are results that show that the development of diseases related to the disease can be predicted. age such as diabetes, heart disease and some aggressive cancers.
Diet and lifestyle to reduce biological age by three years
It is also well known that lifestyle and exercise habits are related to living longer and better.
A recent study proposes that, by carrying out a treatment program of just eight weeks, biological age can be reduced by about three years . The intervention was carried out in a group of 43 people aged between 50 and 72 years, and focused on diet, sleep, exercise, relaxation and supplements such as probiotics and phytonutrients.
Through the epigenetic clock, eating and lifestyle practices are reflected in the methylation patterns observed in DNA. Which means that these habits influence biological age. However, it would be necessary to carry out studies of greater scale and duration to confirm the indicated results.
Aging with health is possible
Centenarians and supercentenarians can display and maintain extraordinary cognitive and physical abilities. Although it depends on the country, the percentage of centenarians without dementia appears to be between 20% and 55%.
Examples are the 118-year-old woman who, in a neuropsychological test, scored even slightly better throughout the 6 months that the test lasted. Or that of the 113-year-old woman whose score on another type of test was the equivalent to that of healthy adults between 60 and 75 years of age. When the latter died, at the age of 115, no type of cerebrovascular pathology or significant atherosclerosis was detected, and only a slight amount of aggregates that are usually related to dementia, even though she did not suffer from dementia in life.
As indicated, healthy aging without dementia is possible, even with the presence of lesions detected after death. Therefore, it is necessary to establish and implement appropriate measures and interventions for these long-lived people, so that their cognitive, physical, social, cultural and emotional well-being is promoted to the maximum.
Santiago Ramón y Cajal said that “old age is a chronic disease, necessarily fatal, that we should all avoid and that, however, we all want.” At least we grow old healthy.
Francisco José Esteban Ruiz, Associate Professor of Cell Biology, University of Jaén
This article was originally published on The Conversation. Read the original.
