It's the one thing hotter than the weather these days – sultry summer sex. You can all but fan yourself (among other things) thinking about it.

But what is it about the summer season that makes us so much more aroused?

There are a number of reasons summertime awakens one's libido. Males, in particular, respond greatly to external, visual triggers, like the sudden influx of women in bikinis, sundresses, mini-skirts and halter-tops. But it's not just this full moon effect of the scantily-clad that has us all howling with desire:

— Sunlight warms the libido.

You're likelier to feel more consumed with lust when it's sunny. It's hypothesized that sunlight helps to produce a hormone, MSH, which is linked to sexual desire. Also, sunlight stimulates the pineal gland, which reduces the amount of the body's hormone melatonin, elevating our mood and awakening our sex drive.

— Everyone looks sexier.

Men are hotter than ever; their summer clothes are showing off those toned arms and firm buttocks. Women have a sun-kissed, blushed appearance – the same appearance we have right after sex. This is the time for women to strip down and flaunt their assets, like our cleavage. Finally, a tan makes our curves and muscles seem more prominent, so we sport fewer clothes. No matter what your gender, feeling better about your healthy summer self helps you to exude confidence and project energy that is infectious – and sexy!

— There’s nothing like sweaty sex.

Salty kisses, the slick sliding of body parts, and wet hair spraying droplets of water onto your lover are among the many sensations that make sweaty sex raw and uninhibited.

On a summer’s evening, in a sweltering bedroom . . . the wetter, the better!

Couples hit every inch of their bed. No position goes untried. No sheet goes unsoaked. In creating sweaty, summer sex sessions, couples forgo air conditioning and make their own rainforest in no time.

— People quit hibernating.

Many lovers hole up in winter, eating more, exercising less, and are pathetically lazier. This sluggish state can affect one's sex life, making for less action. The “let there be light” of summer takes on whole new meaning in shaking off the winter blues. As lovers soak up the sun, their spirits are lifted and their energy levels swell. They are moving more, eating lighter meals – and feeling better about their physiques. Lovers find themselves in a completely different state of mind, with sex on the brain.

— Rest and relaxation.

Couples tend to go on vacation during the summer, reaping the benefits of a romantic destination. Submerged in a new environment, they thrive off a sense of adventure that emboldens their sexual ventures. With vacation lending itself to better moods, lovers find themselves experiencing increased sexual desire and response.

Being away from their laptops and cell phones further boosts a couple's summer "sexperiences." Far from office and home demands, couples feel more relaxed. The effects of simply loosening up make for more amazing intimacy, and many couples experience a boost in the quality and quantity of sex. They also appreciate the fact that they're focusing on nothing more than their relationship and each other.

— Becoming one with nature.

Summer means hiking for a lot of couples, which invites plenty of opportunities for outdoor sex. Deep in the woods and feeling one with the Earth, lovers can shed their inhibitions and go for an animalistic shag.

— Bare, smooth skin.

With bikini season comes increased nether region maintenance. Lovers step up their grooming, shaving, plucking and waxing on a more regular basis. This invites more sensations, which can have people bearing even less.

— Skinny dipping.

Summer's red hot couple can't resist an inviting body of water. A cool dip doesn't snuff out the action, however. Between weightlessness, new maneuvers, and getting wet, couples adore water sex. Just don't forget to come up for air!

— Sex on the beach.

Whether on a private beach or tucked under a big beach towel, couples like to get fresh on the seashore. Those with exhibitionistic tendencies seem to enjoy such sex even more. The risk and danger of getting caught produces dopamine, which stimulates sexual excitement. No matter what, it doesn't hurt to have a beach umbrella handy.

Just remember, no matter what the time of year, sex, like any other exercise, can result in overheating if you exert yourself for a long period of time in a hot, humid space. If you long to make love in such an environment, avoid dehydration, by drinking plenty of fluids. Taking out-of-control action to a cool shower can help keep your motor running at a comfortable temperature as well.

In the Know Sex News . . .

— New York City to Buy Female Condoms. In an effort to curb HIV/AIDS, New York City’s Department of Health and Mental Hygiene has allotted $2 million to make female condoms available in health clinics and organizations citywide. Health officials said they need to increase the supply due to the condoms’ popularity. These condoms cost about $3 a piece, versus the male condom, which sells for $1.

— Safe Sex Programs Really Do Benefit Teens. A study from the University of Kentucky found that safer sex programming appears to nurture positive attitudes toward practices that help to avoid the acquisition of sexually transmitted diseases. Approximately 48 percent of the nearly 19 million cases of STDs that occur in the U.S. every year are among those between the ages of 14- and 24-years-old.

— Pregnancy Intention Impacts Timing of Birth. According to an article in Perspectives on Sexual and Reproductive Health, women who do not intend to get pregnant have a greater likelihood of having a preterm birth.

Dr. Yvonne Kristín Fulbright is a sex educator, relationship expert, columnist and founder of Sexuality Source Inc. She is the author of several books including, "Touch Me There! A Hands-On Guide to Your Orgasmic Hot Spots."

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