L-theanine partially counteracts effects of caffeine on sleep

L-theanine partially counteracts effects of caffeine on sleep

SummaryCaffeine is known to inhibit short-wave deep sleep. Rats given L-theanine and caffeine showed a measurable increase in short-wave sleep, counteracting the negative effects of caffeine. 

Citation: L-theanine partially counteracts caffeine-induced sleep disturbances in rats, Jang HS, Jung JY, Jang IS, Jang KH, Kim SH, Ha JH, Suk K, Lee MG, Pharmacology Biochemistry and Behavior, 2012. (Abstract)


Melatonin decreases time to sleep without changing wake-up time

Melatonin decreases time to sleep without changing wake-up time

Summary: Melatonin decreased clock hour of sleep onset by 0.67 hours in adults and children with no change in wake-up time.

Citation: The use of exogenous melatonin in delayed sleep phase disorder: a meta-analysis, van Geijlswijk, Korzilius, Smits, Sleep, 2010. (Abstract)


Magnesium deficiency linked to poor sleep quality

Magnesium deficiency linked to poor sleep quality

Summary: A study of magnesium levels in mice demonstrated that sub-optimal magnesium levels decrease sleep quality as measured by EEG brain activity. 

Citation: Magnesium involvement in sleep: genetic and nutritional models. Chollet D, Franken P, Raffin Y, Henrotte JG, Widmer J, Malafosse A, Tafti M., Behavior Genetics, 2001. (Abstract)


L-theanine increases alpha brain activity and induces relaxation

L-theanine increases alpha brain activity and induces relaxation

Summary: In a study of young adults, supplementation of L-theanine improved relaxation as measured by alpha brain activity. 

Citation: L-theanine, a natural constituent in tea, and its effect on mental state, Nobre AC, Rao A, Owen GN, Asia Pacific Journal of Clinical Nutrition, 2008. (Abstract)


Melatonin shown to improve sleep quality and improve morning alertness

Melatonin shown to improve sleep quality and improve morning alertness

Summary: A study of 170 insomnia patients age 55 years and older showed a marked improvement in symptoms and increase in morning alertness after taking melatonin, indicating it also improves sleep quality.

CitationProlonged-release melatonin improves sleep quality and morning alertness in insomnia patients aged 55 years and older and has no withdrawal effects
Lemoine, Nir, Laudon, and Zisapel, Journal of Sleep Research, 2007. (Abstract)

Magnesium increases slow-wave deep sleep

Magnesium increases slow-wave deep sleep

Summary: Oral administration of magnesium resulted in a decrease of EEG brain wave activity in a study of 12 elderly adults. 

Citation: Oral Mg(2+) supplementation reverses age-related neuroendocrine and sleep EEG changes in humans. Held K1, Antonijevic IA, Künzel H, Uhr M, Wetter TC, Golly IC, Steiger A, Murck H., Pharmacopsychiatry, 2002. (Abstract)



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