When you're stressed out you may feel like "pulling your hair out," but did you ever realize that it can actually cause your hair to fall out?

It's true. "Stress can lead to extra hair [falling out] but it can take a while to manifest," says Kingsley. In fact, "telogen effluvium" is a common hair loss problem that can occur up to three months after a stressful event.

The tricky part is that little can be done to help the situation. "[The hair loss] cannot be curtailed but needs to run its course," says Kingsley who's the first to note that it's a vicious cycle of sorts.

"It's easy to say 'don't be stressed' but this is more difficult than it sounds and the more you worry about [losing your hair], the more stressed you get and the more [that] falls out." The good news is that after the initial loss, hair usually grows back in six to nine months.

But is there NOTHING we can do in the meantime?

Next: What you can do to help keep hair on your head.

Kingsley advises getting more sleep and taking vitamin B supplements -- both are indicated to help keep hair follicles from "releasing the hairs prematurely." He also recommends the "use of a scalp mask that's massaged into the scalp every two to three days before shampooing." Try Philip Kingsley Scalp Mask, $6.82.

Next: Can stress really make your hair gray?

OK, it causes acne and wrinkles and makes your hair fall out, but stress can't really cause gray hair too, can it?

One word. Kinda.

According to Kingsley, "It does appear that stress can cause hair to turn gray faster, although it hasn't been definitively proven. Stress can cause the B vitamins to become depleted, which is associated with being gray," he says.

Next: Is there any way to stave off the graying process?

There is no evidence that we can do anything to reverse the graying process either -- just that we can attempt to slow it slightly by increasing our intake of vitamin B-rich foods like leafy green veggies. (Or you can simply embrace the gray the way these celebs do.)

Next: The toll stress is taking on your nails.

Our nails tell a lot about our health. If they're too soft it can be an indication of malnutrition or chronic arthritis, while longitudinal ridges can point to thyroid disease. And, what about stress? How is it manifested in our nails?

Our nails take the hit both internally and externally. We may bite them or even rub our fingers over our thumbnails in a nervous fidgeting motion, which, according to dermatologist Flor A. Mayoral, MD, causes a distortion of the nail plate and results in ridges. "Sometimes patients with nail problems are not aware that their habits or tics from being stressed out or nervous are at the root of their problem," Mayoral told colleagues at a 2007 conference at the American Academy of Dermatology.

Looking at what happens from the inside, Dr. Murad says, "nails are made of keratin protein. If we damage the cells in the nails by stress, then the nails become weaker." Weaker, more brittle, more prone to splitting.

What, besides general de-stressing and eating well, can be done to offset stress-induced nail nightmares?

Next: Check out reader-approved nail hardening solutions.