Influenza Infection
Conditions
Keywords
tea catechin extracts, influenza infection, prophylaxis, supplements, adults over 20 years old, both men and women
Brief summary
The Purpose of this study is to evaluate the effects of 5 months catechin consumption on the prevention of influenza infection.
Detailed description
Catechins are the major components of tea flavonoids and are reported to possess physiological activities such as antiviral effects. Recent experimental studies have revealed that tea catechin extracts prevent influenza infection, but few studies have been conducted on the clinical effects of tea catechin consumption on the prophylaxis of influenza infection. Based on these backgrounds, we designed a prospective randomized controlled study to evaluate the effects of 5 months tea catechin consumption on the prophylaxis of influenza infection.
Interventions
DIETARY_SUPPLEMENTtea catechin extracts
Tea catechin extracts 540 mg/day, are consumed for 5 months.
Sponsors
White Cross Nursing Home
Masahiro Morikawa
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
20 Years to 90 Years
Healthy volunteers
Yes
Inclusion criteria
* aged over 20 years * possible to maintain without drinking tea more than 250 ml per day during the study * possible to maintain without taking supplements or herbal products including catechin extracts during the study * possible to fill out a questionnaire personally * Obtained written informed consent before participation
Exclusion criteria
* Possessing some chronic infectious diseases in need of therapy * Possessing tea or catechin allergy * Possessing a history of influenza infection before six months prior to the study * diagnosed as inadequate for other reasons to participate the study by principal investigator
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| the incidence rates of influenza infection | Until 5 months consumption of the study capsules |
Secondary
| Measure | Time frame |
|---|---|
| the incidence rates of upper respiratory tract infections | Until 5 months consumption of the study capsules |
| the severity of the symptoms and the duration of the cold among incident cases | Until 5 months consumption of the study capsules |
| occurrence of the adverse events | Until 5 months consumption of the study capsules |
Countries
Japan
Outcome results
None listed