Oleuropein is patented in the US for antiviral activity against various viral diseases, such as herpes, hepatitis, rotavirus, and the rhinovirus. It has also shown efficacy against respiratory viruses like the flu.
For example, in athletes, taking just 100 mg/d of oleuropein cut the duration of sick days by 28%, although it didn’t affect the risk of becoming sick.
Research behind olive leaf’s antiviral effects is still underway, but what data is available suggests olive leaf bolsters our defenses against viruses by:
Interfering with the ability of viruses to dock to cells.
Neutralizing enzymes that viruses need to replicate.
Acting directly on the viral envelope to kill it.
All of these are effects directly relevant to viruses. Additionally, olive leaf affects our immune cell functionality by increasing:
NK cell concentrations (security force)
Helper T-cell concentrations (field generals)
Cytotoxic T-cell concentrations (special forces)
The olive leaf that I like to use and dosages are linked here.
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