Garlic boosts the health of your immune system, and a number of studies have found that animals given regular doses of garlic are better able to ward off viruses like the flu and various strains of rhinovirus, the kind responsible for the common cold. In one study from 2001, volunteers who took a daily garlic supplement were less likely to get colds than volunteers taking a placebo, and even when the garlic takers did get sick, they recovered more quickly. The Journal Of The National Medical Association also recommends using garlic in cold and flu seasons.
For the sake of people who have to talk to you, garlic supplements are probably the kindest way to go. But you can also get the same benefits by chewing on a clove of garlic once a day for prevention, or twice a day to get over a cold or flu. Mince a clove of garlic into some honey if the flavor is too overpowering. (Here's how you can get the best health benefits out of honey.) It’s not clear whether adding more garlic to your cooking affords the same protection, but why not? It'll only taste great.
Related: How To Grow Garlic In 3 Simple Steps