I have been passionate about this on Twitter and I hope it is helping people. This will keep you from getting sick, or if you are sick it will help you recover faster. It comes in two forms: capsules and tablets. The capsules are easier to take, the tablets are horse pills that taste absolutely awful, but they work better. My hardcore regime is 6 tablets 3x a day if I am trying to prevent being sick or if I am sick. For more casual maintenance you can take ~3 to 6 per day. I always bring them on international trips to help with jetlag and protect my immune system. My other travel secret is nuun caffeinated electrolyte tablets - the product is called sport+ caffeine. It's for athletes but I find it so helpful for travel and being in a hotel, it's so convenient to just drop a tab into a glass of water. The hydration from the electrolytes is really helpful for jet lag and I like easy access to caffeine. One of my pet peeves is being away from home and having to get dressed to go out for a cup of coffee or tea, I like to enjoy these things in bed in private - I don't want to see anyone. The nuun tablets are a way to deal with that if there is no coffee maker in the room, although almost all hotels will have a hot water kettle and even if it's not in the room you can usually request it. I travel with my own tea for this reason. I switch between Harney & Sons Paris tea and Mariage Frères Marco Polo because you can get both sachets - and you don’t need a mug to brew tea, you can pour hot water into a glass from the bathroom and it's better anyway because you can see the color of the tea and get the strength just right. One more thought on the nuun tablets - they are amazing for a hangover but i don’t drink anymore so thankfully I no longer have to worry about that. If want to feel “festive” my favorite n/a beer is the pale partake its only 10 calories and not sweet, I just wish they would change the name because it’s really embarrassing and dumb.