he Moon’s Influence on Mood, Sleep, and Behavior: What Does Science Say?
By Dr. Yasser Al-Daghistani

The moon has long held symbolic and scientific significance in human cultures, often linked to emotional and psychological states. But is there a real scientific and biological impact of the moon on our behavior, sleep, mood, and physical health? Recent studies offer intriguing insights.

1. The Moon's Effect on Sleep

A study published in Current Biology (2013) revealed that sleep is influenced by lunar phases. On average, people sleep 20 minutes less during the full moon, take longer to fall asleep, and experience reduced REM sleep.

✦ Melatonin:
During full moons, melatonin production — the hormone that regulates sleep and circadian rhythms — tends to decrease due to increased nighttime light. Even in dark environments, variations in melatonin secretion were noted, suggesting that the human body subconsciously responds to lunar cycles, affecting the biological clock.

2. The Moon's Impact on Mood and Behavior

Other studies link full moon phases with increased emotional disturbances such as anxiety, irritability, and even aggression, especially in individuals with pre-existing psychological conditions.

✦ Serotonin and Dopamine:
Light changes and hormonal fluctuations during lunar cycles also affect key “happiness hormones” — serotonin and dopamine — which play a vital role in mood regulation and emotional stability. A drop in melatonin may disrupt these neurotransmitters, leading to tension, anxiety, depressive episodes, or even heightened energy in certain lunar phases.

3. The Moon, Menstrual Cycle, and Uterine Cramps

There has long been a connection — now supported by science — between the lunar cycle and women’s menstrual cycles, both averaging around 28 days. Some women’s periods naturally sync with moon phases, often starting during the new moon or full moon.

✦ Uterine Cramps:
During full moons, researchers have observed an increase in uterine cramps, particularly in women sensitive to hormonal or lunar changes. It's hypothesized that lunar gravitational forces — much like their effect on tides — may cause subtle shifts in body fluids, including the uterine lining, leading to stronger cramps or fluid retention.

Additionally, melatonin drops during full moons may influence estrogen and progesterone levels, contributing to varying symptoms such as pain, irritability, and fatigue during menstruation.

4. The Moon’s Broader Impact on Human Behavior

While some studies have dismissed a strong link, data from hospitals and emergency centers show spikes in agitation, accidents, and panic attacks during bright lunar nights. Psychiatrists also report increased insomnia and mood instability during these periods.

🔹 Conclusion

Although scientific debate continues, accumulating evidence suggests a genuine connection between the lunar cycle and human sleep, mood, behavior, and hormonal activity. Key effects include:

• Decreased melatonin and disrupted sleep patterns

• Fluctuations in serotonin and dopamine affecting mood

• Increased menstrual cramps and hormonal sensitivity

• Observable behavioral and emotional changes

Understanding this relationship deepens our awareness of how cosmic rhythms influence our bodies and minds, and helps us better align our biological rhythms with nature.