Ever wondered how to get the best bang for the cup? Of coffee at least.
What if I tell you that the best way you can stay awake after drinking coffee is to get some shut-eye?
Ironically as it sounds, it's how you can recharge and make the most out of your tall cup of cappuccino, or a shot of espresso.
In fact, coffee naps are a thing. If you take caffeine before you snooze in the afternoon or whenever, when you wake up you'll feel less groggy, experts say.
The effect comes by getting the benefit of the sleep, add to that the stimulating benefits of caffeine when you wake up. Both caffeine and sleep alleviate tiredness, so the double whammy works well together.
How coffee naps work
Studies have shown that coffee naps are more effective than coffee or naps alone - but we'll get to that later.
For now, here's how coffee naps work.  First, we'll have to thank the two processes for why coffee naps work: how your body tells you it's tired and how it responds to caffeine.
As you go about your day, your body breaks down molecules called adenosine triphosphate or ATP. They're the body's biochemical energy supply and when they get broken down, they leave behind adenosine. As it accumulates, your body gets the signal that it's "getting tired."
Some enzymes in your body are more able to break down adenosine when you're sleeping, than when you're awake.
When you're awake, adenosine builds up. But when you sleep, you're allowing the enzymes to catch up and clear out the adenosine.
The reason why caffeine works in keeping you awake is that it's shaped as an adenosine. When it binds into adenosine receptors, it blocks the actual adenosine molecules. So you feel less tired.
Here's the clincher:
When you bring a nap and caffeine together, you get your ultimate efficient and ultra powerful sleep!
Because it usually takes 20 minutes for caffeine molecules to travel through your body to your brain, you can allow your body to clear out the adenosine in the brain through a 20-minute snooze!
By the time caffeine rushes in within this period, there's much less adenosine to compete with and the caffeine molecules are more likely to bind into receptors instead of adenosine ones that tell your body you're tired.
Be careful not to overdo your snooze time though! Napping that goes beyond 20 minutes makes it harder to wake up. Before you know it, you're waking up from a 2-hour nap. YIKES.
It's one thing to get drowsy at your desk if you're working a 9-5. It's another story altogether if you're driving somewhere and you get drowsy. Loughborough University in Britain did a study and found caffeine naps are great for people who are on the road and have trouble staying awake. 
Falling asleep is always preceded by a period of increasing sleepiness, which drivers are quite aware of, to the extent that will do things to keep themselves awake (opening window, turning up the radio, stretching etc.), but continue to drive rather than 'take a break'. Why do they fail to heed these warnings, believing they won't actually fall asleep and are 'safe' to drive? Young men are the most likely persons to do this, even when they are struggling to stay awake.
The researchers at Longborough University found that no other common measures to combat drowsiness while driving, such as cold air, napping without caffeine, caffeine without napping or a break without a nap, worked as well as caffeine naps in helping combat drowsiness.
In the 1990s, the Loughborough researchers measured brain waves of subjects in driving simulators. The caffeine nap worked better than anything at eliminating mid-afternoon drowsiness and preventing driving errors than in all of the other controlled groups they studied.
They found sleep apnea and even low levels of alcohol in the bloodstream greatly increase the chance of people falling asleep at the wheel.
Sleepy drivers should stop driving and take a 30 minute break at a safe place. We have shown (now recommended in the Highway Code) that a caffeinated drink immediately followed by a short nap before the caffeine kicks in, make an ideal combination for combating moderate sleepiness. Despite advertising claims, some caffeine products are much better and others in this respect, and drinks with a very high sugar content can worsen sleepiness. We are assessing these products and claims.
Another study from Japan found that people who took caffeine naps performed significantly better than those who had not had one.  That study also found that the caffeine nap worked better than a nap alone, a nap and washing of the face or having bright lights shone into the eyes. They were asked if they felt less tired, and they said yes, though this was a subjective measure.
Interestingly, there's even some evidence that caffeine naps can help people go for relatively long periods without proper sleep. As part of one study, 24 young men went without proper sleep for a 24-hour period, taking only short naps. Twelve of them, who were given just a placebo, performed markedly worse on a series of cognition tests, compared with their baseline scores. Twelve others, who had caffeine before their naps, managed scores roughly the same as their baselines for the entire day.
How you should do a coffee nap
Jeff Mann, the founder and editor of SleepJunkies.com, explains the best way to take a coffee nap.  He says there are four main steps. If you don't like coffee, take a caffeine supplement.
The steps are:
Find a good place to nap. If you're at work, go in a room that is little used, where you can turn the lights down, one away from the noise and bustle of your co-workers. He says you could use an eye mask and earplugs, too.
Mann says coffee is ideal, but caffeine supplements are good. Sodas and tea may not be as effective because they don't have enough caffeine and the sugar may give you a sugar and carbohydrate rush. Scientists recommend a dose of 200 mg of caffeine.
Set your alarm to awaken you around 15 to 20 minutes after falling asleep. It's important to wake up before entering a deep sleep. Slow-wave sleep patterns of deeper sleep can make a person groggy after they wake up. Another point is that you want to awaken before the caffeine takes effect.
Now take your nap, without delay.
So if you can find a place to take a quiet nap, try it out. There's very little to lose (just 20 minutes of waking hours) and a whole lot to gain!
To learn more about coffee naps, here's a video from Vox:
Erectile dysfunction. In combination, those are two of the ugliest words known to man. But can caffeine help you get it up?
Science hasn't found the definitive answer to this question, but one study concluded that fewer men who consume caffeine have problems performing. The study said:
Caffeine intake reduced the odds of prevalent ED, especially an intake equivalent to approximately 2-3 daily cups of coffee (170-375 mg/day). This reduction was also observed among overweight/obese and hypertensive, but not among diabetic men. Yet, these associations are warranted to be investigated in prospective studies