Objective: In the present work, we evaluated the effect of the intake of a Jerte Valley cherry-based product (JVCP), compared to a placebo product, on sleep quality, urinary 6-sulfatoxymelatonin (aMT6-s) levels and the serum concentration of interleukin-1β (IL-1β), tumor necrosis factor α (TNF-α) and interleukin-8 (IL-8).
Design: This was a blind, placebo-controlled, randomized, crossover study.
Setting: University of Extremadura (Spain).
Participants: Ten young (20-30 years old), ten middle-aged (35-55 years old), and ten elderly (65-85 years old) participants.
Intervention: A placebo (Kool-Aid®) or JVCP (patent no. ES 2342141 B1) were consumed twice a day, as lunch and dinner desserts.
Measurements: Actigraphic monitoring was used to record and display the temporal patterns of the individuals' activity and rest. Urinary aMT6-s and serum cytokines (IL-1β, TNF-α and IL-8) were also determined.
Results: The consumption of the JVCP improved the nocturnal rest, measured by sleep efficiency, number of awakenings, total nocturnal activity, sleep latency, assumed sleep, actual sleep time and immobility. Moreover, it was detected an increase in both the levels of aMT6-s found in first-void morning urine and the concentrations of serum pro-somnogenic cytokines obtained from samples collected at the acrophase of the melatonin rhythm (1.00 am) in all experimental age groups after the JVCP consumption. Generally, better results were obtained with advancing age.
Conclusion: The ingestion of the JVCP may contribute to establish a high-quality sleep and be used as a potential nutraceutical tool to prevent sleep disorders with the advance of age.