A few studies indicate that caffeine may slightly enhance weight
loss in people who exercise and maintain a low-fat diet. But
there's no evidence that increased caffeine intake results in
significant or permanent weight loss.
Marketers of fad diets and weight-loss supplements often
exaggerate the benefits of caffeine, claiming that caffeine will
significantly curb your appetite and help you drop pounds quickly.
However, clinical studies on the relationship between caffeine and
weight loss don't support these claims.
Here's what researchers have found:
It's important to keep in mind that caffeine is a stimulant that
can increase your heart rate and blood pressure, interrupt your
sleep, and cause nervousness and irritability. Also, many
caffeinated beverages are high in calories, which can contribute to
unwanted weight gain.
Don't listen to me lor. 
but then, just 1 cup of coffee a day, it should be okay la ..
right?
