Safety test of the aromatherapy using the essential oil which was extracted from Abies sachalinensis

INTERVENTION: In before and after that subjects perform aromatherapy using aroma pendant in the morning, we carry out tests of blood, blood pressure, cognitive function and questionnaires. Subjects carry out the aromatherapy for two hours a day and continue for four weeks. In before and after that subjects perform aromatherapy using diffuser in the morning, we carry out tests of blood, blood pressure, cognitive function and questionnaires. Subjects carry out the aromatherapy for two hours a day and continue for four weeks. In before and after that subjects perform aromatherapy using diffuser after 20:00 p.m., we carry out tests of blood, blood pressure, cognitive function and questionnaires. Subjects carry out the aromatherapy for two hours a day and continue for four weeks. CONDITION: Healthy adults (In the future Alzheimer's disease) PRIMARY OUTCOME: The results of blood tests and blood pressure test after four weeks SECONDARY OUTCOME: The results of Touch Panel‐type Dementia Assessment Scale (TDAS) and questionnaire after four weeks INCLUSION CRITERIA: 1) Subjects who are 20‐89 years old at the time of registration 2) Subjects who are not dementia