You can prove it to yourself easily with this simple scientific experiment.
1. Go to a local subway station.
2. Proceed to lick every handle/seat/floor possible.
3. The next day when you are violently ill, on an empty stomach drink an 8 oz glass of Colloidal Silver 15 ppm.
4. When you feel better within hours of drinking it, write down how long it took to feel better.
Now for the double blind part, repeat the steps above.
This time DO NOT drink Colloidal Silver . Write down your recovery time.
Repeat this until you are convinced, or otherwise of it efficacy.
This works with food poisoning too, so instead of a subway post, go raid a dumpster for rotten food.