Night Owls Beware: Teens That Sleep Late are More at Risk with Other Conditions

Teens who sleep later in the day are reportedly proven by studies to be less active, causing them to be more at risk for other health conditions.

Penn State researchers studied the sleep patterns of 377 teenagers and discovered that individuals with a later sleep schedule ate more carbs and were more likely to be inactive, even if they got the necessary amount of sleep.

They claim that sleeping late can interrupt a child's circadian rhythm, or regular day-night cycle, interfere with their social calendars and other duties, and lead to an insufficient diet and decreased physical activity, placing them in danger of obesity and poor cardiometabolic health.

According to the American Academy of Sleep Medicine, sleep is crucial to health. Healthy sleep involves enough length, acceptable quality, proper scheduling and regularity, and a lack of sleep disturbances or disorders.

A delayed sleep pattern, defined as sleep timing that is later than traditional or acceptable in society, is more frequent among teenagers and young adults. Fernandez-Mendoza stated that teenagers' health depends on good circadian alignment.

Factors Working Against Sleep Cycles

While the study focuses on sleep schedules, previous research has shown that stress activates specific neurons in the brain, disrupting the vital phases of sleep, revealing an exciting finding for people who suffer from sleep disorders.

The human sleep cycle is divided into four phases, each with its own set of features and functions. A normal 90-minute cycle has three non-rapid eye movement (NREM) periods and one rapid eye movement (REM) stage.

During these stages, the brain and body experience a symphony of changes, ranging from slower brain waves and lower temperature levels in NREM sleep to memory consolidation and emotional processing in REM sleep.

Enter the preoptic hypothalamus, the orchestrator of this complex sleep symphony. Researchers zoomed in on neurons in this brain area, determining that certain neurons, notably the glutamatergic ones known as VGLUT2, influenced sleep patterns.

The study found that VGLUT2 neurons engage regularly during NREM sleep, regulating important sleep activities. However, stress disrupts this cycle, firing these neurons out of turn.

This uneven activation causes ' microarousals,' interrupting the continuity of sleep cycles and limiting sleep duration.

Less Stress Better Sleep

Researchers have long been interested in the influence of stress on sleep quality, and this work provides solid evidence of a direct effect on neuronal function during sleep.

When participants were stressed, these VGLUT2 neurons increased activity during NREM sleep, fragmenting the sleep cycle and shortening overall sleep length.

Through thorough trials, the researchers demonstrated a direct causal relationship. Stimulating these neurons when asleep immediately promotes microarousals and alertness.

In contrast, blocking VGLUT2 neurons decreased microarousals during NREM sleep, resulting in longer sleep episodes and higher sleep quality.