Brand new research reveals that your testosterone is directly affected by how much sleep you get.

It confirms several recent studies that show that poor sleep can slash the chemical that makes you a man. “We used a method never before used in sleep medicine,” says study author Dr. Christopher Miller, a sleep researcher for the National Institutes of Health.

His method also reveals, for the first time, why sleep and testosterone are so related.

Dr. Miller says his findings unlock the “mechanistic link connecting declining testosterone levels to sleep in men.”

Classic Cycle of Destruction

More and more research links testosterone to sleep…but none of it explains why.

Dr. Miller’s mission was to find that link so he looked at all the research ever published on the two.

“This approach hasn’t yet been used in sleep medicine as it is so new,” he says.

He dug through all the research, looking for one common link.

And he found that “the relationship between testosterone and sleep” was always linked to the “interactions of testosterone and cortisol.”

Cortisol is a hormone produced by your adrenal glands in response to stress.

Every study showed that cortisol is the problem for two different reasons.

• Firstly, it “impairs sleep and promotes wakefulness.” That’s a problem because research shows that diminished sleep slashes testosterone. (More about this in a moment.)
• Secondly, “considerable research indicates that testosterone and cortisol are in inverse proportion.” In other words, when cortisol levels increase, testosterone levels decrease.

Dr. Miller says his findings reveal a classic cycle of destruction. If you don’t get enough sleep, you don’t produce enough testosterone. If you don’t produce enough testosterone, you’ll produce more cortisol. And cortisol stops you from getting enough sleep. That means the problem just gets worse and worse over time.

He thinks it’s why older men have poorer sleep than younger ones…and a lot less testosterone.

“Testosterone levels decline in aging men,” he says. “Cortisol levels increase and sleep quality is diminished.”

His new findings haven’t been printed yet, but an online version is available through the peer-reviewed journal Sleep.

Sleep Slashes Testosterone by 15 Percent

This latest research comes hot on the heels of a study published last year from Dr. Eve Van Cauter from the University of Chicago.

That study showed that just two hours less sleep each night can cut your testosterone levels by 15 percent.

The study was done on 10 men under lab conditions to accurately monitor how much sleep they got and how it affected them.

They spent three nights under lab supervision and got about 10 hours of sleep each night. On the third day, they had their blood sampled every 15 to 30 minutes for 24 hours.

Then they spent the next eight days getting just five hours of sleep each night.

After the eight days, they had their blood sampled again. The blood tests results clear. All the men’s blood testosterone levels dropped by 10-15 percent when they got less sleep.

More research supports these findings. Another study from the University of Chicago got similar results. In this one, Dr. Plamen Penev looked at how sleep affected men between the ages of 50 and 65. He found that less sleep always lowered testosterone levels.

Get More Sleep by Turning Your Body into a Testosterone-Boosting Machine

The good news is that you can reverse the cycle. Cortisol disturbs your sleep and that cuts your testosterone.

But Dr. Miller says you can “counteract the wakefulness of cortisol,” because “testosterone (also) inhibits cortisol.”

In other words, if you boost your testosterone you can reduce cortisol. That will help you sleep better and still stay manly as you age.

There are two things you can do right now to do this.

The first thing is turn your diet into a testosterone-boosting machine. That means eating plenty of healthy protein, because it’s been shown again and again to produce testosterone.

You can give your body all the protein it needs just by eating the best kinds of the right foods.

Start by eating wild-caught fish and avoiding farm-raised seafood.

Be sure to pick only grass-fed beef and free-range poultry. You can also drink organic milk from grass-fed cows. Finally, you should start eating more nuts. Almonds, macadamia nuts and walnuts are all loaded with protein.

You can also boost testosterone through regular exercise. Resistance training has been shown to be really good for this. Most men want to work out their arms or show off doing the bench press. But your quickest way to produce lots of testosterone is to work your legs. That’s because they’re really big muscle groups and produce lots more testosterone.

Some easy exercises to begin with are leg presses, squats or lunges. All of these will kick up your testosterone and help you to get a better night’s sleep.

[Ed Note: Fatigue and lack of energy are not the only ways that low testosterone levels can affect you. But if you’ve noticed that your sex drive is dragging… your pecs have turns into flaccid breasts… or your hair is thinning, low testosterone and lack of sleep may not be the only things to blame. These symptoms could indicate a deeper problem. One that your doctor may write off as a “natural” part of the aging process. Fortunately, you can pinpoint this problem… and fight back. If you want to quickly and easily restore your energy, amp up your libido, and get back to your “fighting weight,” click here now to learn all the details.]