melatonin

Sources:

Melatonin is a hormone primarily known for its role in regulating the body's sleep-wake cycle. Here are some key points discussed by and other experts in various episodes of the podcast:

Function and Efficacy:

  • Melatonin's Role: Melatonin signals the brain that it is time to transition to sleep, but it is not responsible for maintaining sleep throughout the night. It serves more as a "starting official" for the sleep process rather than a conductor 1.
  • Supplementation Benefits: While melatonin can be helpful for older adults due to reduced natural production, studies show it only increases total sleep by an average of 3.9 minutes and sleep efficiency by 2.2% in healthy adults 1.

Cautions on Supplementation:

  • Hormonal Effects: Melatonin supplements often contain concentrations far exceeding natural physiological levels, which can disrupt other hormone systems, particularly those related to reproductive health 2. Prolonged use or high doses can affect bone mass, gonads, and may alter the timing of puberty 3.

    Melatonin and Sleep

    Matt and Andrew discuss the role of melatonin in regulating sleep and whether or not melatonin supplements are effective for improving sleep. While melatonin helps with the timing of sleep, it doesn't necessarily aid in the generation of sleep itself. Studies suggest that melatonin supplementation is not particularly helpful for healthy adults and only increases total sleep time by an average of 3.9 minutes and sleep efficiency by 2.2%.
    Huberman Lab
    Dr. Matthew Walker: The Science & Practice of Perfecting Your Sleep | Huberman Lab Podcast #31
    1
    2
    3
    4
    5
    6
  • Quality and Consistency: Supplements can vary significantly in their actual melatonin content compared to what is listed on the bottle, raising concerns over dosage accuracy 2.

Light and Melatonin:

  • Impact of Light: Exposure to light, especially blue light, can inhibit melatonin production, disrupting sleep. Using minimal light or red light at night can help maintain melatonin levels 4. Consistent exposure to natural light during the day helps regulate melatonin production according to the season 5.

Applications:

  • Jet Lag and Occasional Use: Melatonin can be useful for adjusting to new time zones (jet lag) when used occasionally under guidance, but it is generally advised to favor behavioral approaches like light exposure and temperature regulation 6.

In summary, while melatonin plays a crucial role in signaling sleep onset and has various physiological effects, its supplementation should be approached with caution due to potential hormonal disruptions and dosage inconsistencies. Always consider natural light exposure and consult with healthcare providers before using melatonin supplements.

RELATED QUESTIONS