It's that time of year again: time to make all those New Year's resolutions you don't even plan on keeping. You know the ones: losing weight, de-stressing, making your health a priority.

We adopt these classic resolutions year after year in an attempt to lead a happier and healthier life — but rarely keep 'em because the work involved definitely makes us less than happy.

Until now.

We found the one thing that will help you meet all of your resolutions — all while bringing you lots of pleasure. We're talking, of course, about sex. Getting it on will help you tackle pretty much every resolution on your list — from losing weight to battling stress. No early morning gym class or meditation session required.

Here, seven reasons sex is the only resolution you need in 2016.

Image via AzmanJaka/Getty

Between staying up all night scrolling through endless social media feeds and indulging in just one more episode of our current Netflix obsession, many of us don't get anywhere near the seven to eight hours of sleep the Mayo Clinic says the average adult needs. And since sleep deprivation puts individuals at risk for everything from mental fog to heart disease, it makes sense that many of us want to catch more Zs in the New Year.

Though turning off our devices in an attempt to get more sleep can be a total bummer, turning on our bedside partners for the same purpose definitely is not. "Endorphins released during orgasm can help induce sleep by relaxing the mind and the body," according to "Why Women Have Sex" co-authors Cindy M. Meston and David M. Buss. "But probably more important, during orgasm the hormone prolactin is released -- and there is a strong link between that hormone and sleep."

Just make sure the sex itself isn't snooze-worthy since you need to reach orgasm in order to reap prolactin's sleep-inducing benefits. On the flip side, your lovemaking shouldn't be so exciting that you're getting your heart rate up, which will actually energize you.

Many New Year's resolutions center on looking and feeling better, which can be quite pricey to execute. (Facials and detoxes are anything but cheap.)

Instead of stocking up on anti-aging products, try turning back the clock by getting busy. In a study conducted at the Royal Edinburgh Hospital in Scotland, participants who had sex an average of three times a week were perceived to be seven to 12 years younger than their actual age. (And here we thought the only beauty benefit was tousled hair.) Regular sex leads to the release of hormones like estrogen, which helps promote things like healthy hair and nails and human growth hormone, which helps with skin elasticity.

All that, and it's free? So long, fancy facialist. We'll stick with sex from now on, thanks.

Want to slim down in the New Year? Why hit the gym when you can hit the sheets instead? Research shows sex counts as a "significant exercise" and, according to Web MD, doing the dirty deed for 30 minutes can burn 85 or more calories, depending on the, ahem, intensity with which you get it on.

Try getting on top for a more heart-pumping session that will also help engage and tone your thighs, glutes and ab muscles.

If you often find yourself so sick you can't get out of bed, you may benefit from spending more time in bed -- with someone else, of course. Sure, you could commit to an insanely restrictive diet or suffer through the latest immunity-boosting cleanse to get healthier in 2016, but wouldn't you rather shag your way to fewer sick days?

Research shows that individuals who get some on the regular -- we're talking a mere one to two times a week -- rarely need to reach for that bottle of NyQuil. That's because serial shaggers have a higher level of immunoglobulin A, an antibody that protects the body from cold viruses. Moreover, according to WebMD, getting it on helps lower your risk of heart disease and balances hormone production.