A growing body of studies shows that omega-3s act directly in molecular signaling pathways that reduce inflammation and are thought to have a positive effect on cognitive health. Brain fog is a term that has been popularized in the medical world in the wake of the COVID-19 pandemic. A significant proportion of patients with long COVID reported having cognitive sequelae that were like fogginess. It is defined as a cognitive impairment with characteristic symptoms including problems with concentration, attention and memory, confusion, difficulty understanding what others are saying, reduced mental acuity and mental fatigue. These are episodes of reduced cognitive capacity that are not representative of the person's normal state. This condition can be caused by various factors such as stress, lack of sleep, overwork, depression, hormonal changes due to pregnancy or menopause in women, head injuries, migraine, certain diseases or viral infections, certain medications as well as substance abuse (alcohol and/or street drugs). In this study, we want to test whether omega-3 monoglycerides (MAG-EPA) can modulate the cognitive health of people with brain fog.

The study is divided into two phases. The first will include eight (8) subjects and all will receive the study treatment (MAG-EPA). This is a single arm phase. If signs of improvement in cognitive health are perceived in Phase 1, the study may continue with Phase 2.

Phase two will include forty (40) participants divided into two treatment groups. Assignment to any of the treatment groups will be done by randomization. This phase will be double-blind and controlled by placebo.

Participants will be asked to complete a Brain Fog Scale (BFS) questionnaire at Visit 0, immediately after signing the informed consent form. This questionnaire covers the 14 days preceding Visit 0. The subject will be asked to complete the BFS again at Visit 1, which should take place 14 days after Visit 0. These two questionnaires will provide a self-declared state of the participant's cognitive health in the 28 days preceding the start of treatment. The results of the first two questionnaires (BFS1 and BFS2) will determine whether the participant's cognitive state is severe enough to be eligible for participation in the study. Indeed, an exclusion criterion was written in the protocol to avoid including participants with normal cognitive health. Once enrolled in the study, subjects will be required to complete a BFS every 14 days until day 140, that is to say at each visit as well as at each telephone follow-up in between visits (V1, day 0; T1, day 14; V2, day 28; T2, day 42; V3, day 56; T3, day 70; V4, day 84; T4, day98; V5, day 112; T5, day 126 and V6, day 140).

Treatment will be given to each subject, MAG-EPA in phase 1 or either MAG-EPA or placebo (sunflower oil) in phase 2, to be taken daily from day 0 to day 112 (112 consecutive days in total, also corresponding to 16 weeks of treatment). Every subject will take 3 gelcaps daily for a total dose of 1.5g/day of MAG-EPA or 2.0g/day of sunflower oil. A wash-out period of 28 days, form day 112 to day 140, will follow treatment.

For research purposes, the Omega-3 Index will be measured from blood samples collected at Visit 1, 3, 5 and 6. The Omega-3 Index is a quantitative analysis that measures the blood level of Omega-3. This test is used both to confirm the adherence of subjects to treatment (for all subjects in Phase 1 as well as for the test group in Phase 2) and to control the restriction of Omega-3 in subjects in the control group (the placebo treatment in Phase 2). The Omega-3 Index results are indicative of the treatment received for each subject, therefore, the analysis reports will not be given to research staff who are blinded.

Demographic information will also be noted for every subject to better characterise the study population in each group.

Any adverse change to subject's health will be noted and followed until resolution or other final outcome.

Inclusion Criteria:

1. Participant between 19 and 55 years of age.
2. Participant who reports having mental fatigue and/or frequent memory loss and/or difficulty concentrating and/or inattention, confusion and/or a feeling of decreased cognitive acuity for at least 28 days at the time of selection.
3. Participant who obtains a mean score on the BFS screening questionnaires (BFS1 and BFS2) total of at least 30 and/OR who obtains the following minimum score on at least one of the three factors: Factor 1 of at least 15 and/or Factor 2 of at least 15 and/or Factor 3 of at least 12.
4. Available for the entire duration of the study and willing to participate based on the information provided in the ICF duly read and signed by the latter.
5. Absence of intellectual problems likely to limit the validity of consent to participate in the study or the compliance with protocol requirements, ability to cooperate adequately, ability to understand and observe the instructions of the research staff.
6. Participant having no difficulty in swallowing tablets, capsules or gelcaps.

Exclusion Criteria:

1. Known allergy or intolerance to fish or history of allergic reactions attributable to fish, or to a compound similar to fish oil.
2. Participant who has used omega-3 supplements in the 30 days preceding day 1 of the study.
3. Pregnant or breastfeeding woman as declared by the latter.
4. Presence of dependence on drugs of abuse or alcohol (˃ 3 units of alcohol per day, acute or chronic excessive consumption).
5. Participant included in another clinical study and who is receiving an investigational product or other research treatment.

Sharing participant data require subject consent for sharing. We do not plan to recontact study subjects for data sharing consent.