I frequently hear that beverages with caffeine or alcohol are not good for replenishing fluids and preventing dehydration. But in reality aren't they just a bit less effective at hydrating your body than other beverages? In other words, if you were stuck in the desert with nothing to drink but beer, coffee and cola, would you actually be worse off and die of thirst sooner if you drank these beverages versus not drinking anything at all?

I know that it is extremely dangerous to mix viagra (or other ED drugs) and poppers (amyl nitrate), and that one should wait for 24 hours after using viagra (to let it get out of your system) before using poppers. My question is what is the waiting period after using poppers before it is safe to use viagra? In other words, how long before the physiological effects of poppers wear off?

Why is beta-carotene dangerous for smokers?

Do any alcohols have any specific benefits? As in, is tequila better than vodka? And is red wine the best choice because of its antioxidants?

1) I have had acid coming up my throat from my stomach for the last 3 weeks. It comes up and just burns my throat. What is it? Do I have an ulcer? By the way, I get 3 hours of sleep a night, and my roommate doesn't help the situation.

2) I have recently asked you about my would be ulcer. I shall pose the question again. Lately I have this damn acid coming up my throat. I've been under a lot of stress and have strange sleeping habits. I am also drinking a lot of coffee. I drink about 5 cups of coffee a day and my roommate isn't exactly stress relieving. I go to bed about 3:30am and wake up about 5:45am for crew. Am I dying? Do I have an ulcer? What's wrong with me?

A couple of questions for you: what are the long-term side effects of one abusing prescription painkillers, such as Vicodin? What advice can you give to someone who has gotten off of them to help them stay off???

My friends take Pepcid AC when they drink to reduce the redness on their faces. Is this safe? I'm worried that it will hurt their stomach linings. Please help.

What is "gaming addiction"? Is it a real thing? I can play some games, like World of Warcraft or League of Legends, for a whole day, and I've sunk 150+ hours into RPGs. How many hours in front of a screen are too many?