Does melatonin cause fatigue the next day?
Melatonin is often used as an effective remedy to help regulate sleep, especially for those suffering from sleep disorders, jet lag, or insomnia. However, some users sometimes report a persistent feeling of fatigue or drowsiness upon waking, as if the effect of melatonin lingered too long after sleep. Is this a common side effect of this hormone? Or does it reflect improper use?
1. Incorrect melatonin dosage
One of the main factors that can explain a persistent feeling of fatigue the next day is an excessively high dose of melatonin. When you take an excessive dose of this hormone, it's possible that it will affect your sleep cycle for a longer period, leading to quick sleep onset, but also difficult waking and prolonged drowsiness in the morning. Indeed, although melatonin is generally considered safe, it must be taken in the correct amount to avoid side effects.
Recommended doses vary, but for most adults, a dose of 1 to 3 mg is often sufficient to induce restorative sleep. Taking higher doses (above 5 mg) can lead to an excess of the hormone in the system, which disrupts the natural balance of sleep and wakefulness. If your body receives too much melatonin, you may experience residual drowsiness or a "mental fog" sensation upon waking. It is therefore essential to start with a small dose and adjust it if necessary, while monitoring the effects.
2. Timing of melatonin intake
Another factor that can explain next-day fatigue is the timing of melatonin intake. Melatonin works best when taken in conjunction with your natural circadian rhythm, meaning at a time that aligns with your "internal clock." If you take melatonin too late at night, you risk disrupting your sleep cycle and affecting the time you wake up in the morning.
Melatonin should generally be taken about 30 to 60 minutes before bedtime, as it acts to signal to your body that it's time to rest. If you take it too close to bedtime, or even after, it could prolong sleep and interfere with the activation of your waking system in the morning. This disrupts the natural waking process, which can lead to a feeling of fatigue or lethargy upon waking, especially if your body hasn't had enough time to readjust to wakefulness. Therefore, it's recommended to stick to fixed times for taking melatonin, ensuring it coincides with your own circadian rhythm, to avoid disrupting your biological clock.
3. Individual sensitivity to melatonin
Everyone reacts differently to supplements, and this is also true for melatonin. Some individuals metabolize melatonin more slowly than others, which can prolong its effects beyond the desired duration. If your body has difficulty eliminating melatonin quickly, you may experience residual effects, such as drowsiness or fatigue, several hours after waking. This can particularly occur in people with a slower metabolism or those who take melatonin over a prolonged period.
This can also depend on the formulation of melatonin you are using. For example, sustained-release tablets or delayed-release versions of melatonin are designed to release the hormone gradually throughout the night. If you have an increased sensitivity to this form of release, it could contribute to slower awakenings and a persistent feeling of fatigue in the morning.
Furthermore, certain external factors such as age, diet, or even other medications you are taking can interfere with how your body metabolizes melatonin. As you age, for example, melatonin production naturally decreases, which can affect how your body responds to a supplement. If you are a "slow metabolizer" of melatonin, this could explain why you experience persistent drowsiness upon waking, even after a full night's sleep.
4. Other factors contributing to fatigue
It is also important to note that melatonin is not the only factor influencing sleep quality and the feeling of fatigue the next day. Elements such as stress, anxiety, sleep hygiene, or the quality of the sleep environment can also play a key role in how you feel in the morning. For example, if you are stressed or have concerns before going to bed, this can interfere with sleep quality, making waking up more difficult, regardless of melatonin intake.
Similarly, the quality of your room (temperature, light, noise) and your habits before sleeping (screen use, diet) can influence the feeling of fatigue in the morning. Therefore, make sure you have a healthy sleep routine and consider all these factors to optimize your chances of waking up fresh and rested, even after taking melatonin.
Melatonin is an effective solution for many people suffering from sleep disorders, but it is not without risks if misused. If you feel tired or drowsy upon waking after taking melatonin, it is likely due to an excessively high dosage, incorrect timing of intake, or a particular individual sensitivity. By adjusting the dose, taking melatonin at the appropriate time, and considering your own metabolism, you can minimize these side effects and optimize the effectiveness of melatonin for restorative sleep and a fatigue-free awakening.
Also explore:
To avoid drowsiness: What time to take melatonin?
To understand the effects on memory: Does melatonin cause memory loss?
References:
- Mayo Clinic - Melatonin side effects: mayoclinic .org
- Journal of Clinical Sleep Medicine: Studies on residual effects of melatonin.