I have to admit, bearded guys make me weak in the knees. There's just something about that sexy rough look that gets me every time. A beard that's not too patchy but that heavy stubble or even full beard.

And it's not just me, a recent study conducted by researchers from the University of New South Wales in Australia found that women found men with beards, specifically 10-day-old beards, more attractive. Not just that but guys with full-beards were perceived as better and more protective fathers.

Both men and women had to rate the faces with varying levels of facial hair growth - clean-shaven, five-day stubble, 10-day stubble and full beards. While guys thought clean shaven looked better than a short, five-day beard (because men, judging other men, might be sensitive to the overall level of masculine threat and aggression signaled through full beards), women actually rated smooth faces as the least attractive.

Past studies have found that men with beards look tougher, more aggressive and masculine and would make better romantic partners.

Women participating in a British study in 2008 rated men with full beards as the most masculine, aggressive and socially mature. They were also thought to look five years older, the least attractive and the worst choice for a short-term relationship.

Men with light beards were considered the most dominant, the most attractive and as the ideal romantic partner for the short or long term. This indicates that females are not selecting faces displaying relatively high or low masculinity, but are rather preferring males who are clearly mature but not too masculinised.

Clean-shaven men finished bottom for masculinity, dominance, aggression, and social maturity, and they were the least favoured choice as a long-term partner. They came second-to-last for attractiveness.

Researchers of the study concluded that beardedness affects judgments of male socio-sexual attributes and that an intermediate level of beardedness is most attractive, while full-bearded men may be perceived as better fathers who could protect and invest in offspring.

But beards go way back as having prestige and power. From the dawn of time, a man's beard was a symbol of his honor, sexual virility and social status as a man.

It is even suggested that a beard is a sign of a strong immune system. The theory goes that disease-carrying parasites thrive in body hair and so if a man can sport a beard without getting ill, he must be extra healthy.

According to recent research from the University of Southern Queensland, Australia, a man's beard blocks up to 95 percent of the sun's UV rays and we all know that over-exposure to the sun means a higher risk of melanoma. Actually, four out of five cases in men appear on the face, head or neck and the sun causes up to 90 percent of the visible signs of aging.

There's a reason why bearded men are born warriors. A study published last year in Behavioral Ecology found that bearded men appear more intimidating to other men. The researchers think a beard makes a man's jawline look bigger, which can make him seem more aggressive when he's angry. You know he's a big softie on the inside, so you know there's no reason to fear the beard. You can walk down the street holding his hand on a dark night in confidence.

Maybe it's because of bushy-faced hunks like Ben Affleck and George Clooney, maybe because of the growing popularity of No Shave November or maybe because that scruffy hipster look is so "in" right now. Either way, bearded guys are on the rise. More and more men are checking in with their doctors to grow thicker beards, taking multivitamins and even prescribed medication that stimulates the male hormone dihydrotestosterone. Amazon.co.uk found that sales of beard trimmers have grown by 47 percent this year, too.

So if you're into the burly, testosterone-driven type - like I am -, your man should skip the razor for at least 10 days or more. Or maybe not, if you're one of the women that don’t find beards attractive since there are large cultural differences in perceptions of facial hair as studies have also shown.