When you catch a man checking you out and giving you that subtle once-over, do you know what physical traits he’s looking at and finding attractive, specifically? It turns out there’s a scientific formula to their once-over, and they’re looking for specific features in a woman that, if recognized, will instantly deem them more attractive. Men are designed by evolution to look for certain features in women that are associated with fertility, youth, and good health. This subconscious reproductive fitness assessment is done by a man without him even knowing. Subconsciously, any man will be more attractive to woman who has physical traits that deem her reproductively fit. The male brain is subconsciously seeking women to make babies with and start a family with. These fertility features include healthy-looking skin, bigger hips, larger breasts and buttocks, fat deposition in the cheeks, and larger eyes.

In addition to these baby-making features, men are also attracted to other things such as a beautiful, welcoming smile, whiter teeth and less makeup.

Today’s females often don’t understand that these features are what males find attractive. The media has created unrealistic standards of beauty, where intelligent women with full-time careers feel pressure to look like a photoshopped celebrity. They feel they must spend their hard-earned income on personal trainers, lip injections and hair extensions. Forget about all of that, ladies, because what the male brain is designed to find attractive might be different features than you think. Below are the physical traits that research has proven are most attractive to men:

Large Eyes (And Eye Contact)

Research shows that men find larger eyes to be more appealing and more attractive. Men equate bigger eyes with femininity, health, youth and fertility. Larger eyes are a sign that the woman has higher levels of estrogen, which would make them more reproductively fit. This is because the female sex hormone (estrogen) prevents facial bone growth which causes eyes to be larger and more prominent in the female’s face.

Eye contact is also an extremely powerful component of human attraction. The gaze of a potential sexual partner causes arousal and sexual invigoration. Also, our pupils will dilate when we’re interested in someone, and dilated pupils are therefore found attractive by the opposite sex, since we’re generally more attracted to those who are mutually attracted to us. A lot can be said with the eyes, and a certain look in someone’s eyes can set off a man’s endorphins.

White Teeth (And a Big Smile)

Your beautiful white teeth are a sign of health and good genetics. Some people even associate white teeth with being of a higher status, which is deemed more attractive. Poverty, illness and disease can all cause yellow teeth, and none of those qualities are attractive.

Luckily, those of us with yellow teeth can easily whiten them by booking an appointment for professional teeth whitening with a reputable company such as Stanton Smiles. Whitening your teeth will lead to you smiling more, and a smile is another incredibly attractive quality. A woman’s smile sends a man cues that she is agreeable in nature, positive and approachable. However, a beautiful smile without the matching beautiful teeth won’t have the same effect.

A study done by Match.com showed that the most important trait people look for on a first date is teeth. Out of the 5,500 single adults over 21, 60% of men and 71% of women claimed they care most about teeth for a potential date. Other studies have even suggested a nice smile can lead to success in other areas, like your career.

The  Curvature of Your Spine (In Other Words, a Booty)

Your spinal curve contributes to your big, round bottom. Men find big butts attractive – but it’s the curvature of your spine that really makes your butt ‘pop’ in that sexy, obvious way.

Researchers at Turkey’s Bilkent University showed 300 men photos of female silhouettes with different degrees of spine curvature and asked the men to select the women they found most attractive. The majority of the men were most attracted to the women with a curvature of 45.5 degrees, because it accentuated their butts and made their butts appear bigger.

Your Waist-to-Hips Ratio

One of the more well-known physical attributes men prefer in females is wide hips, but it’s not quite that simple. According to scientists, men specifically prefer a waist to hip ratio of 7:10. Such a ratio is believed to be the perfect one for childbearing. Less than that may signal that the women are not suited for childbirth, while bigger than that could suggest fertility issues relating to being overweight.

Glowing Skin

Smooth, glowing skin is a sign of youth, health, and good life choices. A woman with good skin generally maintains a healthy diet and is generally not a substance abuser. A woman who abuses alcohol or does drugs won’t have the beautiful skin that a woman who makes healthier choices will have. In fact, good skin is one of the few instant indicators of good health that a man will notice when he’s giving you a once-over. That in itself is an attractive quality, but there’s also the added attraction that radiant skin is a sign of fertility.

Thick and Healthy Hair

Thick hair is associated with health, youth and vitality. Hair will thin out when you age or when you lack nutritional health. Long, thick and healthy hair is also a sexual stimulator for men. They associate your lucious locks with sex appeal, beauty and feminity.