A novel nutritional blend of tryptophan, glycine, magnesium, tart cherry powder, and l-theanine reduces sleep onset latency and increases total sleep time and efficiency in healthy adults.
In a randomized, double-blind crossover study with 16 healthy adults, a nutritional blend reduced sleep onset latency by 24 ± 25 minutes (P=0.002), increased total sleep time by 22 ± 32 minutes (P=0.01), and improved sleep efficiency by 2.4% ± 3.9% (P=0.03), while also reducing morning sleepiness (P=0.02). The effects may be mediated by upregulation of key metabolites like 6-sulfatoxymelatonin, D-serine, and L-glutamic acid.
Evidence Score
Study Evidence
Study 1. Nutritional Modulation of Sleep Latency, Duration, and Efficiency: A Randomized, Repeated-Measures, Double-Blind Deception Study.
observationalLangan-Evans C, Hearris MA, Gallagher C, Long S, Thomas C, Moss AD, Cheung W, Howatson G, Morton JP · Medicine and science in sports and exercise (2023)
Result:
Mechanism Graph
Limitations
- ⚠Small sample size (n=16) limits generalizability
- ⚠Short intervention period (3 days) may not reflect long-term effects
- ⚠Dosage of individual components in the blend not specified in abstract
- ⚠Free living conditions may introduce uncontrolled confounding variables despite standardization efforts
Frequently Asked Questions
What ingredients were in the sleep blend tested in this study?▼
The blend contained tryptophan, glycine, magnesium, tart cherry powder, and l-theanine, but the exact dosages of each component were not provided in the abstract.
How much did sleep onset latency improve with the nutritional blend?▼
Sleep onset latency was reduced by an average of 24 minutes (from baseline) compared to placebo, with a standard deviation of 25 minutes and a statistically significant P-value of 0.002.
Was this study blinded and controlled?▼
Yes, it was a randomized, repeated-measures crossover, double-blind deception study, meaning participants were blinded to the study's primary outcome (sleep assessment). 75% of participants remained blinded to sleep as the primary outcome.
What objective measures were used to assess sleep?▼
Objective sleep measures were obtained using actigraphy, which tracked sleep onset latency, total sleep time, and sleep efficiency. Subjective measures included the Pittsburgh Sleep Quality Index, Core Consensus Sleep Diary, and Karolinska Sleepiness Scale.
Products
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References
- 1.Langan-Evans C, Hearris MA, Gallagher C, Long S, Thomas C, Moss AD, Cheung W, Howatson G, Morton JP. "Nutritional Modulation of Sleep Latency, Duration, and Efficiency: A Randomized, Repeated-Measures, Double-Blind Deception Study.." Medicine and science in sports and exercise, 2023. PMID: 36094342 DOI: 10.1249/MSS.0000000000003040