As baby boomers march toward retirement at the rate of 10,000 a day, they are encountering unexpected ailments along the way. These are not diseases that will kill them but nuisances that remind them that they are aging.

Although doctors struggle to explain why the immune system takes a dip between ages 40 and 50, they suggest that the best way to avoid these irritants is to practice a healthful lifestyle. "The key to middle age is to stay active, eat healthy and don't give up," said Dr. Seth Johnson, a family practitioner in Altamonte Springs, Fla.

Here are some ways to slow down and combat five common ailments.

Shingles

This painful skin rash occurs when the virus that caused chickenpox during childhood returns for round two.

Before age 50, the chance of developing shingles is just 1 to 2 percent. But after 50, that chance increases to 2 to 3 percent.

A vaccine can decrease the likelihood of contracting shingles, but Johnson doesn't recommend it for patients younger than 50. The vaccine cuts the risk in half, but it costs $200 to $300.

"If you have a pain you can't explain for a day or two and then see a rash, contact your physician," Johnson said. If untreated, the virus can cause tender water blisters and worse — such as nerve damage.

The most effective treatment is anti-viral medication used within 72 hours of an outbreak, he said.

Vertigo

A sensation of dizziness, benign vertigo is most likely caused by natural aging or a head trauma that lodges tiny crystals into the wrong area of the ear. This sends bad information to the brain and knocks off the sense of balance.

"Every time they lie down or roll over, the whole room starts spinning for 10 to 30 seconds," said ear, nose and throat (ENT) specialist Dr. Jeffrey Baylor.

If you suspect you have vertigo, Baylor recommends being tested by an ENT specialist to rule out more extreme causes such as a tumor or stroke.

If correctly diagnosed by a doctor, benign positional vertigo is treatable through the Epley maneuver, said Dr. Clifford Dubbin, an Orlando ENT specialist. It involves sequential movements of the head, staying in each of the four positions for 30 seconds. "If you know you have it, you can save a week or two of misery and do the maneuver," he said.

He also said benign vertigo can slowly disappear on its own over time.

Weakened depth perception

Reading glasses often become a necessity for aging eyes, but many Americans don't realize that depth perception also can become an issue, even creating a driving hazard.

As vision deteriorates over time, Johnson said, eyes can become less symmetrical. For instance, one eye might see things near while the other sees far. This difference affects depth perception.

Research shows that as depth perception begins to deteriorate, one of the most dangerous driving maneuvers is a left turn in traffic, said AARP spokesman Dave Bruns. The advocacy group has created a defensive-driving program that includes strategies for dealing with loss of depth perception.

Along with dulled depth perception, baby boomers might find that they can't see as well in dim light, which also affects their driving abilities.

Tinnitus

That ringing, buzzing, hissing, sizzling sound in your ears has a name: tinnitus. And it's fairly common among baby boomers. The condition can last for a week to several years.

Tinnitus is related to high-frequency hearing loss, Baylor said, and is cumulative.

Even when you're not at the point of hearing loss, one thing you'll start noticing is a high-pitched ring, experts say. Ringing of the ears makes up for the absence of sound, and once you hear a ring, it's likely to recur.

There isn't a tried-and-true solution for tinnitus, but Baylor said that for patients who have hearing loss and wear hearing aids, there's a 50 to 70 percent chance of recovering.

To prevent the condition, wear earplugs to loud concerts and ear protection at a shooting range, he said.

Menopausal acne

It's like being a teenager again: Oily skin and red bumps can reappear around the time women enter menopause.

For teenagers, acne develops because of a surge in hormones, Knight said. During menopause, estrogen levels drop and testosterone-like compounds form, causing acne. Menopausal acne might not be as severe as a teenager's, but it could last as long as one to two years.

"You do see people who spent their whole adult life without acne" only to develop it at the onset of menopause, Knight said. "And it's frustrating" for them.

Retinoids, more commonly known as Retin-A, help prevent and deal with acne, Knight said. In addition to reducing puffy oil glands, the topical medicine also combats fine lines, wrinkles and skin cancers.