FOCUS – Sleeping late may not be the best choice for your heart

Being a “night owl” — a person who prefers to stay awake and be active late into the night — may be linked to less favorable heart health, according to a study reported by AP.

Researchers analyzed data from more than 300,000 middle-aged and elderly adults in the “UK Biobank,” a large health database.

About 8% of participants described themselves as more physically and mentally active in the late afternoon and evening hours.

According to the researchers, the problem is not necessarily the fact that a person sleeps late.

An important factor may be the mismatch between the body’s internal biological clock and typical schedules of work, food, activity and sleep.

This is linked to the circadian rhythm, the roughly 24-hour biological clock that coordinates many processes in the organism.

This rhythm affects when we feel sleepy or awake, but it is also linked to heart rate, blood pressure, stress hormones and metabolism.

Researcher Sina Kianersi, of Brigham and Women’s Hospital and Harvard Medical School, stressed that people who prefer late hours are not destined to have heart problems.

According to him, the main challenge is adapting the biological clock to the structure of daily life.

The study comes at a time when experts are giving more and more importance to sleep as part of cardiovascular health.

Besides sufficient sleep, important factors are physical activity, healthy nutrition and control of blood pressure, cholesterol, blood sugar and body weight.

Previous data had also suggested that people who stay awake late may more often have several factors linked to cardiovascular risk, including less physical activity and some unhealthy habits.

However, these links do not automatically imply that late sleep is the direct cause of health problems.

In the study, about a quarter of participants were classified as “early birds” — people who preferred morning hours and slept earlier — while the rest fell between the two profiles.

The researchers’ key message is that a regular sleep–wake rhythm and a lifestyle that respects the biological clock may be important for health.

For people who work or live on late schedules, the aim is not necessarily to sleep very early, but to ensure sufficient sleep and as stable a routine as possible.