While the harmful effects of sleep deprivation have been known for years, a new study suggests that excessive sleep may also be detrimental. Researchers found that people who sleep less than six hours or more than eight hours a day show signs of faster biological aging compared to those who sleep more.
The results showed that the optimal sleep duration ranges between 6.4 and 7.8 hours per night, as those who sleep within this range exhibited fewer signs of aging.
Junhao Wen, the study's lead author, said the findings do not mean that sleep alone controls the rate of aging, but they do suggest that too little or too much sleep may be a sign of declining overall health.
The study, conducted by researchers from Columbia University's Irving Medical Center, relied on data from nearly half a million participants in the UK's biobank.
The researchers used artificial intelligence techniques to analyze what are known as "biological clocks," which are tools that measure the functional age of organs and tissues, not the chronological age of a person.
Biological aging refers to the gradual decline in the efficiency of bodily functions, including the ability of cells to repair themselves, which increases the risk of disease and death.
The researchers based their measurements on a variety of data, including medical images, proteins, and metabolic indicators, to analyze the condition of 17 organ systems in the body across 23 different biological clocks.
The team was able to build multiple models to measure organ aging, such as the liver, based on different biomarkers, which allowed for a deeper understanding of the impact of sleep on the body’s health.
The study showed that lack of sleep was associated with higher rates of depression and anxiety, as well as obesity, type 2 diabetes, high blood pressure, heart disease and heart rhythm disorders.
Too little or too much sleep has also been linked to respiratory diseases, such as asthma and chronic obstructive pulmonary disease, as well as digestive disorders, such as gastritis and acid reflux.
Researchers believe that prolonged sleep may affect mental health through changes that occur in the brain and body fat percentage, especially in older adults.
Wen emphasized that the importance of the study lies in demonstrating the deep relationship between sleep and the functions of different body organs, noting that good sleep is essential for maintaining metabolic balance and the health of the immune system.
Health experts advise maintaining regular sleep schedules, reducing screen use before bed, and avoiding caffeine in the evening to improve sleep quality.
The study was published in the journal Nature.
