It would be almost too good to be true that the world's most popular mood-altering substance would also help with weight loss.
But is there actual truth to this? Let’s find out.
While many popular, non-medical websites report caffeine does help with weight loss, Mayo Clinic says that the effects are probably minor and short-term. The esteemed medical institution reports that there may be minor weight loss associated with caffeine consumption, and perhaps some aid in keeping the weight off. 
If there is a causal connection, however minor, there are a couple of theories as to how it may work:
Registered dietitian Katherine Zeratsky writes for Mayo: 
Some studies looking at caffeine and weight were poor quality or done on animals, making the results questionable or hard to generalize to humans. In addition, some studies found that even decaffeinated coffee may contribute to modest weight loss, suggesting that substances or factors besides caffeine may play a role in weight loss.
Dr. Bob Arnot told People magazine that caffeine consumption can increase human metabolism to the point where the body burns 100 extra calories per day. Sounds modest given Americans' calorie-rich, fatty diets. But in a year that's 36,500 calories! That equates to a weight loss of about 10.4 pounds a year because to lose 1 pound the body must burn about 3,500 calories. To extrapolate, in four years you could lose 41.6 pounds just from caffeine consumption. Though I hesitate to say a person could actually lose that much weight just from drinking coffee without proper exercise and diet. 
Ms Zeratsky points out that if there is any connection between weight loss and caffeine consumption, it may be entirely canceled out if you drink beverages with a lot calories.
Starbucks, for example, is notorious for its high-calorie drinks. The 10 highest-calorie, 20-ounce drinks at the popular chain range from more than 500 to more than 600 calories, which would certainly negate any modest weight-loss or calorie-reduction benefit you might get from the caffeine they contain.
To know more about how much calorie there is on Starbucks drinks, watch this video:
The bottom line: Be cautious about using caffeine products to help with weight loss. When used in moderation (400 milligrams or less) by healthy adults, caffeine is generally safe. But too much caffeine might cause nervousness, insomnia, nausea, increased blood pressure and other problems.
While the jury of medical experts appears to still be deliberating about any purported weight-loss associated with caffeine, studies have shown it has a number of very beneficial effects on people. A New York Times article covered these studies, as follows: 
If you want to learn more, here are 7 surprising benefits of coffee.
Let's allow the Obesity Action Coalition to have the last word on whether caffeine boosts weight loss: 
Some research has suggested that caffeine may stimulate thermogenesis - a scientific name for the way your body generates heat and energy from the calories in your food; but nutrition experts say that this effect probably isn't enough to produce significant weight-loss. Caffeine may also reduce your desire to eat for a brief time, but again, there's no good evidence over the long-term that this effect leads to weight-loss. To date, no conclusive clinical studies have been done to determine the long-term effect of caffeine on weight loss, and the smaller studies that have been done show a lot of variability in the outcomes.
In fact, the coalition gives a warning:
At present, even though caffeine may have a small effect on energy and appetite that could lead to some positive short-term effects on your energy balance, there's no evidence that it can actually cause you to lose weight. On the other side of the equation, excessive caffeine consumption clearly can be harmful.
So, while caffeine may or may not help with weight loss, as long as you don't consume too much it won't harm you and may actually provide a plethora of health benefits.
Unless you work outdoors or indoors in a job where you are physically active all day, it can be difficult for some people who have desk jobs to stay awake at work without caffeine.
Maybe the most important thing you can do to make sure you don’t nod off at work is to get a good night of sleep, at least 7 to 8 hours, at a regular time every night. Boredom can also cause you to nod off. Other than getting a good night’s sleep and having a fascinating job, there are things you can do to stay awake.
How do investment bankers stay awake on their 18-hour shifts?
Investment bankers work such long hours that many resort to chemical stimuli. There have been rumors of methamphetamine and cocaine use among investment bankers to burn the midnight oil. Other investment bankers take Ritalin or Adderall, which are given to children with ADHD but which are stimulants for adults. But the mainstay is probably coffee, energy drinks, and other concoctions containing caffeine.
Some law students spend 60 hours a week studying. Those who’ve been through law school advise prospective students to leave the Xbox at home so they’re not tempted with potentially ruinous distraction. How do law students get energy to study so much?
One thing many law school students do not do is party and socialize a lot. This has a doubly salutary effect because the time spent not partying is time they can spend studying. And then they are not out of sorts, hung over or over-tired the next day from partying.