When I feel a cold coming on, I reach for the varieties I know will build up my immune system to fight off illness completely or at least reduce my symptoms. Here are the top 10 I like to curl up with during cold and flu season: In addition to being steeped in tea, elderberry can be found as a syrup and is a common ingredient in cold and flu medicines. I prefer to take echinacea in tea form, so I can sip it throughout the day. Pro tip: Increasing the steep time will increase its dosage and potency. Slippery elm contains bioflavonoids, tannins, calcium, and vitamin E, all of which provide their own unique health-boosting properties. Pu-erh is classically known to come from the Yunnan province in China. Studies have pointed to Pu-erh having antibacterial properties, which means it can help fight off harmful bacteria. So next time you are feeling under the weather, grab your largest mug, your coziest blanket, and curl up with one of these cold- and flu-fighting teas! A cutting-edge nutrition deep dive taught by 20+ top health & wellness experts