. . . is why astronauts like horseradish and tabasco sause. Other hot foods, too. Turns out that without gravity, there can be no post nasal drip. Which sounds like a good thing, but it really isn't. If your sinuses don't drain, then you are constantly stuffed up. And hot foods like shrimp cocktail with lots of horseradish work zero-G medicinal wonders. Even if the shrimp do taste like card board.