Update: A previous version of this article contained quotes from an expert whose credentials are now in question. We have reached out to him for confirmation of those credentials and have not heard back. You can read Gizmodo’s investigation here, and his response here. INSIDER has updated this article as of 3/1/19.

Though an orgasm isn’t necessary for sex and masturbation to feel pleasurable, few will deny that reaching the big “O” is a great added bonus.

But beyond just feeling great, an orgasm also brings with it a host of unexpected health benefits, many of which you likely had no idea about.

Whether you’re climaxing with a partner or during a solo session, orgasms help with all kinds of things, from lowering stress levels and heart attack risk to giving your skin a natural glow.

INSIDER spoke with Dr. Felice Gersh, M.D., an OB-GYN and founder/director of the Integrative Medical Group of Irvine in Irvine, CA and author of the upcoming "PCOS SOS: A Gynecologist's Lifeline To Naturally Restore Your Rhythms, Hormones and Happiness," to learn the mental and physical health benefits of orgasms.

You'll feel closer not only to your partner, but with others in your social orbit as well.

Foto: You can thank oxytocin for that feeling of closeness.sourceFlickr/John Jones

If you've ever felt that telltale desire to snuggle up next to your partner after reaching orgasm, you can also thank oxytocin for those loved-up feelings. But it turns out that this powerful hormone can help you feel closer with others in your social circle too, not just your sexual partners.

According to a 2012 study by evolutionary psychologists at the University of Michigan and Albright College in Pennsylvania, "the more one's partner was likely to fall asleep after sex, the stronger the desire for bonding," said Daniel Kruger, research fellow at the University of Michigan, and lead author of the study.

"Oxytocin plays several roles involving mood. Since successful reproduction requires peaceful cooperation among family members, touching and hugging increases oxytocin, as does breastfeeding and having orgasms," explained Dr. Gersh, adding that "whichever way it is stimulated and produced, it increases the feeling of love and bonding."

In 2013, researchers Mark Ellenbogen and Christopher Cardoso looked at the effects of oxytocin on your social orbit outside the bedroom and found that "instead of the traditional 'fight or flight' response to social conflict where people get revved up to respond to a challenge or run away from it, oxytocin may promote the 'tend and befriend' response where people reach out to others for support after a stressful event. That can, in turn, strengthen social bonds and may be a healthier way to cope."

Orgasms can help lower the risk of prostate cancer in older men.

Foto: Ward off prostate cancer by having sex.sourceHalfpoint/Shutterstock

Regular and frequent ejaculation can help ward off prostate cancer, per a decade-long study published in the British Journal of Urology International, which determined that ejaculating at least four times per week can lower a man's risk for prostate cancer by up to 30% in men over 50.

Dr. Gersh explained this link, telling INSIDER, "We know that having sex and orgasms is beneficial for every aspect of male health. The male reproductive system fares best with regular use, and the prostate belongs to that system. The more ejaculations, the better off he'll be."

They can help regulate your menstrual cycle.

Foto: Regular orgasms might foster regular cycles.sourceSarah Schmalbruch/INSIDER

According to a 1978 study published in the peer-reviewed scientific journal Psychoneuroendocrinology and carried out by researchers at the University of Pennsylvania, regular orgasms can also help regulate your menstrual cycle, even when you're not on your period.

"The exact mechanism is unknown but may link to the circadian rhythm. [Regular orgasms] improve immune health, mental health, and likely circadian health," explained Dr. Gersh. "We know that the ovaries are very circadian and have melatonin receptors and respond negatively to inflammation. Regular orgasms will work on all these levels to maintain our innate rhythms and lower inflammation, fostering regular cycles."

They can also help boost fertility.

Foto: "The impact of orgasms on fertility, by supporting a healthy immune system, is truly amazing."sourceRawpixel.com / Shutterstock

Regular orgasm can help with fertility, as shown by a 2015 study from researchers at the Indiana University. They found that "sexual activity triggers physiological changes in the body that increase a woman's chances of getting pregnant, even outside the window of ovulation," which means that orgasms bring benefits at any point in your fertility cycle.

According to a 2015 article in Berkeley Wellness, a publication by the School of Public Health at the University of California, Berkeley, "Orgasm's health benefits may also include improving the odds of conception. One idea is that vaginal and cervical contraction during orgasm draws in sperm. Women who have an orgasm have been found to have more sperm in their cervical mucus."

As Dr. Gersh told INSIDER, "The impact of orgasms on fertility, by supporting a healthy immune system, is truly amazing. Regular orgasms keep the immune system functioning with the right organization during the different phases of the menstrual cycle to optimize successful fertilization and implantation of the embryo. And this process is facilitated by frequent sex, at times when ovulation isn't even happening."

Orgasms can help during the dreaded cold and flu season, too.

Foto: Orgasms are killer for your immune system, and they are a lot more enjoyable than cough syrup.sourceFlickr/Laura Taylor

The quickest way to warding off that cold can be found in the bedroom as well as on the shelves at your local drugstore.

A 2004 German study found that immediately after sexual arousal and subsequent masturbation to climax, 11 men showed increased levels of leukocytes, white blood cells that help protect your body from illness and infectious disease.

But the benefits aren't just for men - that same 2015 study from Indiana University showed that sexually active women had "greater changes in helper T cells," which help activate the cells your body needs to fight off foreign invaders that cause disease and illness.

They can also increase your threshold for pain and help alleviate pain.

Foto: Having sex can help alleviate pain largely due to the release of feel-good hormones called endorphins during climax.sourceCW

Whether you're battling menstrual cramps or a headache that won't quit, an orgasm can help set you on the track to feeling better. A 2013 study from the University of Munster in Germany, showed a link between sexual activity and headaches and migraines, with 60% of participants reporting an improvement of their migraine attack, and 70% of them reported moderate to complete relief, largely due to the release of feel-good hormones called endorphins during climax.

Those benefits are closely linked to the aforementioned immune benefits, with Dr. Gersh telling us, "Orgasms lower stress [and improve sleep]. Together this can impact perceived pain [through] down-regulation of pain sensitization pathways and by modulating the immune system to lower levels of inflammation, [thus] reducing pain levels."

Orgasms can help keep your brain sharp.

Foto: You might find yourself excelling at the office.sourceAndrey Noskov / Strelka Institute

The flood of hormones released in an orgasm sends a ton of messages throughout your body, increasing brain activity, particularly in women. A 2013 study by Rutgers University researchers showed that orgasm in women during masturbation caused the brain to light up in the cortical, subcortical, and brainstem regions.

As Dr. Gersh added, "By improving sleep, lowering stress, and improving sociability," the brain will see benefits from orgasm ... and "these benefits are more powerful than doing challenging crossword puzzles," she noted.

Your stress levels will be reduced.

Foto: Our experts agree that the post-coital payoff is major, and it's all thanks to that oxytocin.sourceShutterstock

Though an orgasm initially brings a flood of stress hormones through your body, studies have shown that the resulting effect is reduced stress levels.

Regular orgasm can benefit your heart as well.

Foto: Also, since any sort of physical activity helps your heart pump more efficiently, it's no surprise why sex can, too.sourceFOX

Your heart keeps you going, but you likely never linked a solid heartbeat to the big 'O,' right? But regular sexual activity can seriously benefit your heart's health, helping to lower cardiovascular risk in older men and women.

A 2016 study published in the Journal of Health and Social Behavior showed that sexual quality and sexual frequency lowered chances of hypertension and rapid heart rate among those over 65.

Similarly, in 2010, a study published in the American Journal of Cardiology showed that men who engage in regular sexual activity had a lower risk of developing cardiovascular disease than those who don't.

That post-coital glow is real, too.

Foto: The post-sex flushed look is a real thing.sourceFlickr/george.schon

If you've ever noticed that your skin is more glowy and radiant post-sex, you can thank the increased blood flow from your orgasm.

Your skin is your body's biggest organ after all, and if you're under stress, it can show by way of a sallow, stressed out complexion. But when you climax, blood vessels throughout the body open up, helping to stimulate collagen production and give you that flushed look, according to Healthline.

Collagen is what keeps skin looking plumped and youthful, which is why orgasms can help skin look its best. As Dr. Gersh pointed out, "Anything and everything which improves mood and sleep and reduces stress, is a benefit to skin," making orgasms the quickest - and cheapest - way to gorgeous skin.

Orgasms can help boost your self esteem.

Foto: "There is a powerful interplay between one's self-esteem and one's sexual health."sourcepixabay

When you feel in tune with your sexual needs and desires, it makes sense why your self-esteem might be higher, but it turns out there's a proven link between sexual health and self-esteem.

In 2011, researchers at the Johns Hopkins Bloomberg School of Public Health found that "sexual pleasure among young adults (ages 18-26) is linked to healthy psychological and social development," with measures of "self-esteem, autonomy, and empathy" highest among young women particularly. Young men showed higher levels of empathy, with Adena Galinsky, Ph.D., co-author of the study noting that "Our hypothesis is that empathetic individuals are more responsive to a partner's needs, and thus initiate a positive feedback cycle."

Dr. Gersh agreed, telling INSIDER, "There is a powerful interplay between one's self-esteem and one's sexual health. Of course, [the effect is] circular, so the ability to easily achieve orgasms grows self-esteem, which, in turn, better facilitates achieving orgasm."

They can even help you live longer.

Foto: Want to live longer? Have more sex.sourceFlickr/wackelijmrooster

Both experts agreed that the benefits of orgasm extend throughout a person's life, and can possibly even extend your life as well.

A four-year Welsh study studied 918 men between the ages of 45 and 59, and found that those with "high orgasmic frequency" lowered their mortality risk by as much as 50%. The men that had two or more orgasms a week died at a rate half of the men who had orgasms less than once a month, proving that "sexual activity seems to have a protective effect on men's health."

As for women: over the course of an eight-decade study on married heterosexual couples initially conducted by Stanford psychologist Lewis Terman in 1921 and carried out through 2011 by Howard S. Friedman Ph.D. as part of The Longevity Project, researchers found a link between orgasms, health, and longevity, particularly in women who orgasmed frequently, who lived longer than their female counterparts who didn't.

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