Understanding Epigenetics and Ageing

Ageing is a universal biological process, but it happens at such a tremendously different rate among people. There are those who are physically and mentally active at old age and those who are old before their time. This discrepancy has prompted scientists to consider the role of genetics, but extend it to epigenetics and ageing, which is the study of how genes become active with time, without necessarily changing their sequence.

What is Epigenetics?

Epigenetics is a field of study that describes molecular alterations that regulate the time and manner in which genes are expressed. These epigenetic changes occur in life, and they are influenced by the environment, food, and stress. They have the ability to affect the rate at which we age at the cellular level, either slowing it down or speeding it up.

Learning about the epigenetics of ageing can not only be used to explain why individuals age variably, but it can also help to understand how lifestyle decisions can be used to change the course of the ageing process itself.

The Science Behind Epigenetic Ageing

The alterations in gene regulation patterns with age are predictable and are referred to as epigenetic ageing. The most researched of them is the process of DNA methylation, which is the attachment of small chemical groups to certain regions of the DNA molecule. The latter serves as signals that regulate the activity of some genes or their silence.

Advanced epigenetic clocks such as GrimAge and PhenoAge can predict chronological age with over 90% accuracy and show strong associations with disease risk and mortality.

A systematic change in the pattern of DNA methylation occurs with age, creating what scientists refer to as epigenetic clocks, which, with mathematical models, provide an approximation of the age of an individual on an epigenetic scale, which, in most cases, is not the same as the chronological age. In addition to DNA methylation, histone modifications and non-coding RNAs influence gene expression during ageing by reshaping chromatin structure.

When comparing the two ages, scientists make certain discrepancies: there are people who seem to be younger or older biologically, though they are of a particular age. Such a difference can be health or lifestyle status, or risk of disease. Research findings indicate that accelerated ageing in epigenetics is associated with a high risk of chronic illnesses, including heart and metabolic diseases.

Biological Age vs Chronological Age

Chronological age is straightforward; it is simply the number of years passed since birth. Biological age, on the other hand, is an indicator of the performance of body systems. It is a combination of molecular, cellular, and physiological indicators of health, which can vary substantially between individuals of the same chronological age.

To give an example, a 60-year-old who exercises, eats well, and avoids stress might be biologically at age 45, whilst another individual of the same chronological age who lives an unhealthy lifestyle might be biologically at age 70.

One way to estimate biological age is through epigenetic age, which is based on molecular patterns. Epigenetic age acceleration occurs when it exceeds chronological age, and epigenetic age deceleration occurs when it is less than chronological age. Epigenetic age usually correlates with worse frailty, heart disease, and early mortality when it is higher than chronological age, and with better health when it is slower.

Accelerated epigenetic ageing links to higher disease risk. Factors such as diet, physical activity, stress, and environmental exposures significantly influence this rate. Lifestyle interventions (healthy eating, exercise, stress/sleep management) have shown potential to slow or even modestly reverse epigenetic ageing, suggesting a way to shape one's biological ageing path.

Factors Influencing Epigenetic Ageing

Epigenetic ageing rate has a high range of differentiation in individuals and is influenced by external and internal factors. These factors can hasten or decelerate the rate of accumulation of epigenetic alterations within the lifespan.

• Genetic predisposition
  There are some inherited factors that influence the body's ability to maintain and repair DNA. The genetic background also influences baseline epigenetic stability; however, in most cases, lifestyle is a more important factor in the long-term consequences.

• Environmental exposures
  DNA methylation can change more rapidly due to pollution, smoking, and prolonged psychological stress. Exposure to harmful substances over an extended period of time causes oxidative stress and inflammation, accelerating epigenetic ageing.

• Nutrition and metabolism
  There is a close relationship between the quality of diet and epigenetic processes. Whole foods, fruits, and vegetables are associated with a slower rate of epigenetic ageing, and processed food and excess sugar are associated with an accelerated rate of change.

• Physical activity
  Exercise supports mitochondrial function, helps reduce inflammation, and is consistently linked to slower epigenetic ageing.

• Psychosocial and socioeconomic factors
  Epigenetic changes and ageing are associated with low socioeconomic status and persistent stress, indicating that the social environment can directly influence biological processes.

In general, epigenetic ageing is a dynamic interplay between genes and lifestyle. Through the determination of the risk factors that can be changed, one can potentially shape their biological ageing path.

Lifestyle interventions to modulate epigenetic ageing

Epigenetics is linked to ageing, and therefore, research has shifted in the direction of finding lifestyle interventions that would slow or even reverse epigenetic changes. Despite the fact that the field is still in development, a number of strategies have been proven to be promising in the initial tests.

• Dietary patterns
  A healthy diet rich in fruits, vegetables, whole grains, and healthy fats helps in maintaining healthy methylation. Nutrition literature indicates that diets rich in nutrients and based on vegetarian foods can lower the indicators of epigenetic ageing, making them some of the key foods that help you age well.

• Physical activity
  Exercise also enhances cellular metabolism, improves blood flow, and reduces inflammation. Both human and animal studies have repeatedly demonstrated that physically active people age with slower rates of epigenetic ageing.

• Sleep and stress management
  Persistent stress increases the level of cortisol, which interferes with DNA methylation. Meditation, mindfulness, and breathing exercises are capable of stabilising epigenetic stress response marks. The proper sleep normalises hormonal balance and helps cells to repair.

• Integrated lifestyle interventions
  A pioneering controlled trial has shown that an integrative programme, which includes diet, exercise routine, sleep management, and stress management, reversed the epigenetic age of participants by nearly two years in only eight weeks. More research is needed, but the results show the effectiveness of the holistic lifestyle.

Through healthy living, people are able to maintain genetic stability, decrease the risk of diseases and probably increase their health span.

The future of epigenetic research and healthy ageing

The correlation between epigenetics and ageing suggests that ageing is not just about time running out, but about alterations in biological processes. The changes in epigenetics happen throughout life and affect the functioning, repairing, and stress response of the cells. The study on biological age and chronological age provides valuable insights into health and longevity.

Even though not all determinants of ageing are modifiable (i.e. genetics or early-life environment), there is currently an increasing body of literature that lifestyle aspects (nutrition, exercise, stress management, and sleep) can be used to control epigenetic ageing. The solution is to embrace healthier lifestyles that preserve a younger biological profile and slow age-related deterioration.

Frequently Asked Questions

1. What is the distinction between biological age and epigenetic age?

Epigenetic age is a measure of molecular alterations in gene regulation, and biological age is a measure of general health in terms of the body and cells. They are not identical but only related.

2. Are lifestyle interventions the answer to epigenetic ageing?

Investigations into this preliminary suggest that lifestyle interventions, including balanced nutrition, exercise, and stress reduction, have the potential to delay or slightly reverse the process of epigenetic ageing, although evidence on this remains developing over time.

3. Is biological age the only age that can be measured by epigenetic ageing?

No. Biological ageing is also evident in other biomarkers such as telomere length, protein composition, and metabolic markers. When these are combined, it makes a fuller picture.