The Fluctuating Nature of Epigenetic Clocks Throughout the Day

The human body is a complex system, with cells that contain a genetic code determining how proteins are made for survival. However, researchers in Lithuania have discovered that small modifications called epigenetic changes act as ‘genetic switches’, impacting the interpretation of instructions within our cells. These changes accumulate over time and are often used to estimate the biological age of cells and tissues.

In a study conducted by scientists in Lithuania, multiple blood samples from a 52-year-old man were taken every three hours over a 72-hour period. The researchers analyzed 17 different epigenetic clocks within each collection of white blood cells and found surprising results. Thirteen out of the 17 epigenetic clocks showed significant differences throughout the day, suggesting that our cells might appear ‘younger’ in the early morning and ‘older’ around midday. The relative differences observed were equivalent to approximately 5.5 years’ worth of changes.

The findings from this study have important implications for the accuracy of epigenetic age estimations. The researchers pointed out that relying on a single tissue sample might not provide a comprehensive picture of an individual’s biological age. This is because white blood cell subtype counts and proportions fluctuate throughout the day, affecting the interpretation of epigenetic clocks.

It is clear from the research that conducting epigenetic tests at different times of the day could yield varying results. A single measurement at a specific time might not capture the full scope of age-related changes in cells. Therefore, to obtain the most accurate assessment of cellular age, scientists might need to collect multiple samples at different times of the day.

The fluctuating nature of epigenetic clocks throughout the day opens up new avenues for research in understanding age-related changes in cells. By taking into account the variations that occur over a 24-hour period, researchers could enhance the precision of age predictions and potentially improve risk assessments for age-related diseases in populations.

The study conducted by researchers in Lithuania highlights the importance of considering the fluctuations in epigenetic clocks throughout the day. By recognizing the dynamic nature of cellular aging, scientists can further refine their understanding of biological age and its implications for health and disease.