When it comes to your health, protecting against osteoporosis and heart disease shouldn’t be your only concerns. STDs are a real risk for sexually active adults over 50.

More than 16 percent of all new HIV/AIDS diagnoses are in adults 50 or older, according to the Centers for Disease Control (CDC). The CDC now encourages those between the ages of 13 and 64 to be tested for HIV/AIDS as part of their regular health screenings.

See also: Discreet ways to get condoms and STD tests.

Between 2005 and 2009, the rates of syphilis increased 67 percent and diagnoses of chlamydia jumped 40.5 percent among those 55 and older; the rates of gonorrhea declined in the over 55 age group but still represented more than 2,200 new cases nationwide.

Laura Berman, Ph.D., assistant clinical professor at the Feinberg School of Medicine at Northwestern University and author of Real Sex for Real Women: Intimacy, Pleasure and Sexual Wellbeing, believes that boomers are at increased risk for STDs in part because they are more sexually active than previous generations, thanks to performance-enhancing drugs such as Viagra.

While boomers may have better sex lives than their parents, they’re less likely to be educated about the risks than their children or grandchildren. "[The over-50 population] is a group that feels like it’s not at risk for STDs,” says Berman. "Some Baby Boomers still believe in the adage, ‘Nice girls don’t carry condoms.'"

There is also a belief, according to Berman, that since the possibility of pregnancy has passed, so has the need for condoms. But that’s not so. As you get older, condoms become even more important for protecting your sexual health.

After menopause, the vaginal walls are thinner and more susceptible to tears, which can increase the risk of contracting or transmitting STDs. A lack of natural lubrication can also increase the likelihood of vaginal tearing and create more entry points for infection, notes Berman.

"After you’ve gone through menopause, it’s even harder to recognize the symptoms of STDs," says Vanessa Cullins, M.D., vice president of medical affairs at Planned Parenthood Federation of America. For example, changes in vaginal discharge that are often associated with certain STDs may be passed off as symptoms of menopause and go unchecked.

The little blue pill has also been linked to higher STD rates: A study published in the Annals of Internal Medicine found that men who take drugs for erectile dysfunction are more likely to have an STD infection than their non-medicated peers.

"You can have an active, healthy sex life long after you turn 50, but you need to protect yourself," says Berman. To help you, we’ve compiled information on the most common STDs.

Next: HIV/AIDS. >>