What's the deal with caffeine?

Can someone please explain to me what is the deal with caffeine?  I have seem many references to avoiding it, but am not sure if there is a link between it and weight loss or what????  I don't drink a lot of it, maybe a cup of coffee in the mornings (not every morning)...usually a diet coke during the day at school......I do drink tons of water, but haven't cut out caffeine completely....do I need to?

i drink 2 to 3 large coffees every day... i also drink a lot of water... i think the issue with caffeine is that it dehydrates you if you don't replenish with water and that a lot of people do the cappucinos or put a bunch of sugar and milk or cream in their coffees, making them high calorie...

i dreink my coffee black and i make sure to replenish with water.. i also hav ethe occasional diet coke and it hasn't affected me negatively in the weight department.

Some studies say that a small amount of caffiene everyday boosts your metabolism slightly. 

Some people claim that a lot of caffiene hinders their weight loss, forget the exact science they reference though.

I know that a lot of people on here, myself included, didn't cut caffiene out completely, but limits the intake to 1-2 servings a day.  Drinks with caffiene "tend" to be high in calories, so it's definately good to avoid them.

Ok I have NOTHING to back this up with, but I did read it some time ago and it scares me to this day since I have a pretty substantial Diet Coke habit.

It was said that caffeine inhibits the trigger your body sends out that tells insulin "ok, we're done. stop storing up calories". That would make your body store more fat than you normally would if you drink a lot of caffeine. My fear of no caffeine is much higher than my fear of fat apparently since I still drink a ton of it a day.

Another forum  I go to had a heated debate on this subject. One very knowledgable guy posted study after study showing NO correlation between weight gain and caffeine, so I was relieved.

I never quit my morning coffee I believe in moderation of anything if you constanstly sit down and swig any kind of artificially flavored or caffienated drink all day long im sure its not good for you. The way I see it im changing so much of myself that i deserve that much needed am coffee sit and enjoy it with my hubby before he goes to work. Im not giving that up hehe

I drink 1-2 cups of coffee in the morning, then usually a diet coke in the afternoon and sometimes another coffee in the early evening (esp. if I have plans for that night). I've lost 17 lbs, so I am thinking that there really isnt a correlation with weight gain. If anything I feel that coffee helps me because it gives me a boost of energy that without, I'd be sluggish and unmotivated to move.

New studies show that caffiene does not dehydrate you and you can count your cup of coffee the same as any other liquid you intake.

More info: http://www.medicinenet.com/script/main/art.as p?articlekey=50654

As for the other questions about caffiene and weight loss...  You can find studies that say it helps, and other studies that say it hurts.  (Google "caffiene weight loss" -without the quotes, and you'll see arguments on both sides.) 

I personally don't worry about it day-to-day although if I'm going to work out I do try to get some caffiene in a bit before due to many studies that show that caffiene helps your body start burning fat quicker than it would otherwise do.  Does it actually help?  Who knows?  -I certainly don't go out of my way to alter my diet in regards to caffiene.  The only thing that's proven enough for me to focus on is calories, so that's what I focus on.  The rest is just unproven, so I give it no more attention than is deserved.

One last note -too much caffiene and/or not enough sleep can lead to high stress levels.  There's also some new research about the stress/cortisol connection to retaining weight (triggering the body's resistance to weight loss just like going into "starvation mode").

The above makes me pay attention to my stress levels a lot more these days.  If I'm stressed, relaxing helps me out mentally and reduces my over-eating due to stress -and if the cortisol stuff turns out to be correct too, well, then it helps that much more.  So, if you find yourself so over-caffinated that you're jittery and getting stressed, yeah, I'd say you should cut back to a more comfortable level.  Me; I only have a cup a day 'cause Starbucks is expensive and I haven't acquired a taste for drip coffee just yet ;-)

I don't know about weightloss factors, but caffeine is a legal addictive drug.

Also, caffeine dialates blood vessels, including the blood vessels in your head.

http://en.wikipedia.org/wiki/Caffeine#Overuse