I'm not going to claim that correlation equals causation, but I will say that on Monday, my coworker and I had the same horrible throat pain.
On Monday night, I started taking elderberry syrup.
By Tuesday, he went home sick.
Wednesday, he stayed home sick.
Me? I kept taking elderberry syrup, and but for the spring allergies, I feel pretty good.
Like I said, I make no claims of causation here. I'm just pointing out a correlation.