Caffeine may help men wake up in more ways than one (wink, wink)

The latest study on the magic, wake-up juice found that men who drink two to three cups of coffee a day may be able to reduce their risk of erectile dysfunction by 42 percent.

Danny Gallagher
CNET freelancer Danny Gallagher has contributed to Cracked.com, Mental Floss, Maxim, Break.com, Mandatory, Jackbox Games, Geeks Who Drink and many, many other publications in his never-ending quest to bring the world's productivity to a screeching halt. He lives and works in Dallas. Email Danny.
Danny Gallagher
3 min read

Refill please. Colin McDonald/CNET

Science can't seem to make its mind up whether caffeine is good or bad for us.

One week, we might get a study saying caffeine is more likely to cause aliens to plant their spawn in our chest cavities, and the next, we might get another saying the stuff can give us the ability to fly and walk through walls.

Recently, caffeine got another line of chalk in the win column, thanks to a study from the University of Texas Health Science Center at Houston. Researchers there found that men who drink approximately two to three cups of coffee a day may have a lower risk of erectile dysfunction.

The study, filed in April in the open-access journal PLOS ONE and publicized by the university on Wednesday, looked at data from a National Health and Nutrition Examination Survey of over 3,700 men 20 years old and above. The data showed that men who drank between 85 and 170 milligrams of caffeine a day were 42 percent less likely to suffer from ED, and men who drank between 171 and 303 milligrams per day had a 39 percent lower chance, according to the journal's abstract.

What's the correlation? The research suggests that caffeine leads to the relaxation of arteries in the penis, as well as the muscle that lines its cavernous body, thus increasing blood flow.

The data even showed that men who were obese or suffered from hypertension -- two factors that can lead to ED -- could still experience a drop in their chances of suffering from the condition if they fell into the same caffeine intake range. The only exception was with men who suffered from diabetes because "diabetes is one of the strongest risk factors for ED," according to David S. Lopez, lead author of the study and an assistant professor at UTHealth's Epidemiology, Human Genetics & Environmental Services Department.

Coffee fans will be pleased to know that this isn't the only health benefit that caffeine can give you, according to some other recent scientific research. Studies suggest it can also lower your risk of being diagnosed with type-2 diabetes and even protect against different types of cancer such as liver cancer.

On the other hand, coffee may have its drawbacks. The Mayo Clinic says drinking too much of the stuff can cause conditions like insomnia, headaches and muscle tremors. It can also cause problems for children if their mothers drink it during pregnancy, and a recent study published in the International Journal of Obesity found it could lead to childhood obesity. It can also increase the risk of heart disease for some people with a certain genetic mutation in their DNA.

So, depending on the state of your health, the truth probably lies somewhere in the middle. However, can someone just tell us if coffee is mostly good or bad already? If I wanted a bigger headache in the morning, I'd just smack myself in the face with a shovel first thing out of bed and move on to my next daily task.