Mechanisms Underlying the Sleep Promoting Effect of Cherry Juice Standardized to Its Proanthocyanidin Content

This study will consist of 4 visits - 1 screening visit and 3 treatment visits. Screening visit will consist of a fasting chemistry panel, a health questionnaire, an Insomnia Severity Index, the Epworth Sleepiness Scale, the Pittsburgh Sleep Quality Index, the Beck Depression Inventory, the State-Trait Anxiety Inventory, and the Fatigue Severity Scale.

Ten subjects passing screening will take for 2 weeks between dinner and bedtime in a blinded and balanced order: 1. Eight ounces of cherry juice standardized to its proanthocyanidin content in the morning and 8 ounces of cherry juice standardized to its procyanidin content 1-2 hours before bedtime for 14 days; 2. A similar amount of placebo juice with the same timing for the cross-over. There will be a 2-week washout between each of the treatment periods. Subjects will be scheduled for two overnight PSGs, one at the end of each two-week treatment period. On the morning following each test the insomnia severity index and other questionnaires will be repeated. The order of the placebo juice and cherry juice will be random and balanced.

Inclusion criteria

• Healthy male or female with a usual bedtime between 9 pm and midnight.
• 65 years of age or older.
• Sleep problem >3 nights per week, meeting the International Classification of Sleep Disorders (ICSD-2*) diagnostic criteria of insomnia for at least 6 months.
• An insomnia severity index ≥ 10 and a minimum of 30 minutes of either sleep-onset latency (SL) or wake after sleep onset (WASO).

*ICSD-2 general criteria for insomnia:

• A complaint of difficulty initiating sleep, difficulty maintaining sleep, or waking up too early, or sleep that is chronically non-restorative or poor in quality.
• The above sleep difficulty occurs despite adequate opportunity and circumstances for sleep.
• At least one of the following forms of daytime impairment related to the nighttime sleep difficulty is reported by the patient:
• Fatigue or malaise.
• Attention, concentration, or memory impairment.
• Social or vocational dysfunction or poor school performance.
• Mood disturbance or irritability.
• Daytime sleepiness.
• Motivation, energy, or initiative reduction.
• Proneness for errors or accidents at work or while driving.
• Tension, headaches, or gastrointestinal symptoms in response to sleep loss.
• Concerns or worries about sleep.

Exclusion criteria

• Diabetes.
• Sedating or hypnotic medications.
• Any chronic medication that has not had a stable dose for 1 month or longer.