The nice thing about modern medicine is that we have an arsenal of antibiotics that's able to wipe out bacteria with a wallop. Pop this pill, banish this bacterium. And that's a good thing. But it doesn't mean you should rely on medicine to address your chronic immunity issues, especially because there are plenty of foreign invaders (some we know and some we have no way of predicting) that won't respond to medicinal attacks. That's why we recommend you add other weapons to your security team.

YOU Tip: Get More 3s. Since we're eating more grains and foods with omega-6 fatty acids, you likely need more sources of omega-3 in your diet to strike the best nutritional ratio—not only to boost your immunity but for all other health benefits associated with omega-3s. Plus, the right ratio reduces the inflammatory stimulus in the liver, so the appropriate inflammation caused when our immune system defends us against an invader does not age us as much. Some fats, like flaxseed oil, have a good balance between 3s and 6s, but you should also add more 3s in the form of purselain and fish such as cod, halibut, and trout. Other ideas: Buy omega-3-enriched eggs, or eat walnuts or the pure DHA form of omega-3 from the same place that the fish get it — plankton.