Still feeling guilty about that second cup of coffee?
Chances are, you shouldn’t be.
Whether you start each day with a latte or rely on a shot of espresso to get over the mid-afternoon hump, a healthy, moderate caffeine habit can provide many health benefits.
This doesn’t mean you should go guzzling energy drinks or pounding espresso shots, of course. Using too much caffeine, or any other stimulant, can be dangerous.
In moderation, though, a caffeine habit could be good for you.
It's natural to grow increasingly tired throughout the day -- our brains naturally produce more and more of a molecule called adenosine from the time we wake up until the time we go to sleep. Scientists think this helps us get to bed at night.
Caffeine hijacks this natural process by mimicking adenosine in the brain. It latches onto the receptors designed for adenosine, pushing them out of the way. As a result, we're left feeling more alert and awake.
One of the common reasons people use caffeine is to help them focus on a task, and no wonder: one of the more clear mental effects of caffeine is a boost in the ability to focus, especially for someone who is fatigued.
Research shows that commercial drivers who cover long distances are significantly less likely to crash if they have consumed caffeine in any form -- coffee, tea, pills, or energy drinks.
However, most people are familiar with caffeine jitters too -- if you consume too much of it, it's hard to focus on anything.
If you've ever had a killer migraine, you've likely tried Excedrin, an over-the-counter medication marketed specifically for these types of rare, severe headaches. What you might not know is that in addition to traditional pain relieving ingredients like ibuprofen and acetaminophen, Excedrin contains caffeine.
There's some evidence that caffeine, when combined with certain pain-relieving medications like acetaminophen (the main active ingredient in Tylenol) and aspirin, helps those medications take effect quicker, last longer, and increases their effects.
For example, a 2007 study of 24 people who took either caffeine and the painkiller acetaminophen, either drug alone, or a placebo found that those who'd taken the combination of (as opposed to either one alone) saw a stronger decrease in pain symptoms that also tended to last longer.
Men who drink the equivalent of at least two cups of coffee a day are about 40% less likely to have erectile disfunction, according to some recent research from The University of Texas Health Science Center at Houston.
David Lopez, an assistant professor at UTHealth and the lead author of the study, thinks this may be because caffeine can help relax certain essential arteries and muscles and improves blood flow, though more research would be needed to say that for sure.
The study included people who got their caffeine from a variety of sources, including coffee, tea, soda, and energy drinks, so the source of the caffeine seems to be irrelevant. And though the findings applied equally to healthy and obese men, diabetic men unfortunately did not experience this same reduction in risk for ED.
One of the things that's most rarely discussed with regard to caffeine is that it is, in fact, a drug. It has psychoactive effects, changing the way we feel and interact with the world around us.
It's the most commonly used psychoactive drug in the entire world, which is probably why we don't think about it as a drug. Yet think of how many of us can't -- or won't -- get through a day without it (this writer included).
Harvard neuroscientist Charles Czeisler thinks that caffeine, combined with electricity, allowed humans to escape natural patterns of sleep and wakefulness, breaking them free from the cycle of the sun, essentially enabling the 'great transformation of human economic endeavour from the farm to the factory,' according to a look at this miracle drug in National Geographic. It enables the modern world.
Research from multiple studies done over the past few years suggests that drinking coffee regularly and in moderate amounts, such as two to three cups per day, may help protect against certain diseases, including type 2 diabetes, liver cancer, and Parkinson's disease.
In several large, international studies, researchers found that people who drank moderate-to-high amounts of coffee each day (between 3 and 4 cups) had an even lower risk of developing diabetes type 2 than people who drank a small-to-moderate amount of coffee, although there appeared to be benefits to drinking any amount.
These studies don't confirm that drinking coffee reduces peoples' risk of disease, of course, but merely show a relationship between the two.
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