Many resources site "possible" benefits of garlic.
I have personal, anecdotal evidence.
Anytime I get a "common cold," garlic does a number on it for me - and fast.
However, I'm not sure it has the same effect on everyone.
One of my best friends is Indian and uses lots of garlic in her cooking.
She & her son still get sick a lot in the winter, but they also have asthma and a slew of different allergies.
Plus, I "mega-dose" raw garlic when I get sick.
Not everyone can or wants to eat that much for various reasons.