The effects of the seaweed extract were evaluated on the animal model equivalent of depression compared with a control group treated with the carrier (spring water) and a reference group treated with Imipramine and showed significative effect. This clinical trial was intended to confirm in humans the potential efficacy identified in animals. The primary objective was to compare against a placebo the effect of Ulva L.L extract in healthy volunteers whose anhedonia was characterized by a component of depression.

The trial comprised three visits: a medical enrollment visit on D0, an intermediate visit on D28 and a final visit on D84. A psychologist made a telephone call after 7 days to check there was no sudden change in the subject's depressive state. During the visits, the subject was examined by a doctor and the psychometric tests were administered by a psychologist. Outside the visits, the subject was monitored by a self-reporting questionnaire in the manner described below.

After obtaining informed written consent and validating the inclusion and exclusion criteria, notably the absence of MDE as per DSM V, the investigator enrolled the subject in the trial. The physician described the subject's demographic and general clinical characteristics, the main medical and surgical history and any current treatment if those pathologies were still present, and any previous antidepressant, anxiolytic or neuroleptic treatments. The doctor asked the subject to complete the SHAPS and QIDS -SR questionnaires and item 7 of the HAM-D. The doctor then handed the subject self-evaluation questionnaires explaining how to complete them and the dates at which they were to be completed. The physician gave the patient a batch of the placebo or a batch of Ulva lactuca as per the randomization. The doctor told the subject a psychologist would be in touch after one week by telephone to check no DSM V severity criterion had arisen.

The investigating doctor saw the subject again at the four-week intermediate visit and at the final visit at the end of the 12th week of follow-up. The doctor collected the self-questionnaires at these visits and the same items as at the enrollment visit were recorded by the physician for describing how the items had evolved and notably the SHAP scale score, the QIDS-SR and item 7 of the HAM-D. In addition, the physician recorded the subject's satisfaction with the treatment evaluated on the PGII (Patient Global Improvement Impression), reported any undesirable affects and gave his/her own opinion on the efficacy of treatment using the Clinical Global Improvement Impression (CGII).

Inclusion Criteria:

• Men or women aged between 18 and 65 years
• Presenting a anhedonia with a score ≥5 on the SHAPS Scale
• Declaring feeling low for at least 4 weeks characterised by a component of depression evaluated on the QIDS-SR
• Being able to apprehend and fill in the evaluation scales

Exclusion Criteria:

• Subject with a major depressive episode as per the DSM V scale, with a HAM D > 8, already on anxiolytic, antidepressor, neuroleptic or any other medicinal treatment liable to influence mood (e.g. benzodiazepines) in the last 30 days or using illegal psychotropic substances, or a with daily alcohol intake of more than three glasses of wine
• Presenting a psychiatric disorder or in state of post-traumatic stress or having had an electroconvulsive therapy in the last 6 months
• Female subject pregnant or breast-feeding or of childbearing age and not using effective means of contraception
• subject suffering from an allergy or intolerance to seafood products (fish, shellfish and seaweed)