Effects of Lemon Verbena Extract Supplementation in Sub-ADHD Children

Effects of Lemon Verbena Extract Supplementation on Behaviour Mood and Cognitive Function in Sub-ADHD Children

The aim of this study is to investigate the effects of 15 mg/kg lemon verbena, in comparison to placebo, on the attention deficit hyperactivity disorder (ADHD) type behaviour and cognitive function of children who do not have a diagnosis of ADHD, but who exhibit high scores (highest tertile) on ADHD behaviour parameters. Multiple aspects of mood will also be assessed.

The proposed randomised, double-blind, placebo-controlled, parallel groups design methodology will assess the psychological effects of 15 mg/kg lemon verbena extract and a matched placebo prior to and after 4 and 8 weeks of supplementation. The trial will utilise the COMPASS cognitive assessment system (Northumbria University) and a range of mood measures during laboratory testing visits.

Parents and children will also take part in a concomitant smartphone study, comprising the collection of the parent's assessment of the child's behaviour/cognitive function and the child's self-report of the same, plus their mood. These assessments will take place on Days -1, 14, 28, 42 and 56.

Inclusion Criteria:

• Are in good health as reported by themselves and their parent/guardian
• Are aged 8 to 17 years at the time of giving assent and parents giving consent
• Have a sex and age-related BMI less than the 98th centile according to the local NHS guidelines
• Are rated by their parents as having a high score (T score of ≥60) on both the Connors 3 subscales of Inattention and Hyperactivity/Impulsivity.
• Have no current diagnosis of ADHD
• Have no relevant food intolerances/ sensitivities/ allergies
• Are not currently using any illicit, herbal or recreational drugs including alcohol and nicotine products
• Are not currently taking prescription medications
• Have not taken dietary supplements e.g. Vitamins, omega 3 fish oils etc. in the last 4 weeks
• Do not have a diagnosed neurological condition, or learning/behavioural or neurodevelopmental differences (e.g. dyslexia, autism)
• Do not suffer from visual (including colour blindness) impairment that cannot be corrected with glasses or lenses (that may impact task performance in the opinion of the PI).
• Do not have any pre-existing diagnosed medical condition/illness which will impact taking part in the study
• Consume less than 250 mg/day of caffeine.
• Can complete all of the study assessments at the training visit
• Are not currently participating in other clinical or nutrition intervention studies, or have in the past 4 weeks
• Are compliant with regards to treatment consumption
• Have not taken antibiotics within the past 4 weeks
• Do not have any health condition that would prevent fulfilment of the study requirements (this includes non-diagnosed conditions for which no medication may be taken)