Dietary Influence on Serotonin in Cognitive and Emotional Functioning in Women

Dietary Influence on Serotonin in Cognitive and Emotional Functioning in Women Using a Tryptophan-rich Protein Over 19 Days

The purpose of this study is to determine whether a chronic dose of a tryptophan-rich protein drink (lumiVida™) can improve cognitive function, emotional processing and sleep in middle-aged women. In addition, also genetic predictors of susceptibility to an increase of Trp levels will be investigated.

lumiVida™ is considered a dietary supplement, and therefore it is not an approved drug by the Food and Drug Administration (FDA). It is regulated like a food. The U.S. Food and Drug Administration does not strictly regulate herbs and dietary supplements. The investigators do not claim that this supplement is meant to treat any ailment

The treatment conditions are either placebo or lumiVida™ (N=30 per group) 0.5 g twice a day (total 1 g/ day). The first testing took place on the screening day (baseline). Subsequently, participants were supplied with supplements for 19 days intervention (sachets which had to be dissolved in 200-ml water). After 19 days, participants were tested again (same tests as on the baseline day). An additional facet was the completion of a 'sleep diary', which asks questions about sleep quality and latency, and bed-time mood, as well as allowing recording of timing of supplement taking.

Inclusion Criteria:

• Physically and mentally healthy (defined by not concurrently receiving medical/pharmacological treatment (except mild painkillers), free of gastrointestinal complaints, not in pain, not diagnosed with a psychiatric disorder
• Female
• Aged: 45 - 65 years

Exclusion Criteria:

• Having received treatment in the last 12 months for: depression, anxiety, neurological disease including migraine, dementia, epilepsy, Parkinson's.
• History of any psychiatric or neurological illness in the last 2 years.
• Current medication targeting the brain (except mild painkillers, e.g. pure paracetamol, ibuprofen), including steroids, e.g. for contraception, Hormone Replacement Therapy (HRT), drugs for weight control, stimulants (e.g. phenylephrine, ephedrine), antihistamines, and some herbal or nutritional remedies including St. John's Wort, 5-hydroxy-tryptophan, or melatonin (which can affect the serotonin system).
• Pregnancy
• Current gastrointestinal complaints
• Diabetes (Type 1 or 2)
• Body mass index < 18 or > 35