Colon screening starts at 45.

Ask your doctor where you stand.

You're in your 50s. It's the prime of your life -- or it should be. Don't let illness rob you of your health.

When you go for your annual physical, make sure your doctor performs or recommends these simple tests that may save your health -- and your life -- later. (Note that your doctor may recommend other tests based on your personal health profile.)

Colon cancer screening is recommended for everyone at age 45. Colon cancer is the second-leading cause of cancer deaths in the U.S. When you turn 45, your chance of getting it goes up. Colonoscopy is the test most frequently recommended, though there are other options. Ask your doctor which screening test is best for you.

Stepping on the scales. This is the age when most people start gaining weight. Watch this weight gain carefully, and fight back with healthier eating and exercise. Being overweight puts you at high risk for getting a number of diseases -- and studies show that weight loss can improve your odds.

Blood pressure. Untreated high blood pressure is an equal opportunity killer: It kills your heart, your brain, your eyes, and your kidneys. Don't let hypertension sneak up on you. Get your blood pressure checked. It's simple, it's cheap, and it's quick.

Cholesterol profile. Do you have high cholesterol? Find out -- at least once every 4-6 years (or more frequently if you have high cholesterol and you're at risk for a heart attack). Controlling your cholesterol can add years to your life.

Blood sugar. Untreated diabetes can destroy your health, causing heart disease, kidney failure, and blindness. Don't let it. Get a fasting blood sugar test or other screening test for diabetes or prediabetes at least once every 3 years, and take control of diabetes early.

For women only: Pelvic exam and Pap smear. Combining a Pap test with a human papillomavirus (HPV) test can safely extend the interval between cervical cancer screenings from 3 years to 5 years in many women between the ages of 30 and 65. Women over age 65 can stop getting screened if they’ve had at least three consecutive negative Pap tests or at least two negative HPV tests within the previous 10 years, according to the guidelines. But women who have risk factors for cervical cancer such as smoking, a history of HPV, or a more advanced precancer diagnosis should continue to be screened.

For women only: Mammogram. By their 50s, all women should have started routine mammograms to help detect any early signs of breast cancer. Your doctor can tell you how often you should repeat the test. Early detection of breast cancer can save your breast and your life.

For men only: Prostate cancer screening. At age 50, men should discuss with their doctor whether they should be screened for prostate cancer and when that screening should happen. African-American men, and those with a close relative who had early-onset prostate cancer, should talk to their doctor at an earlier age.

Looking for moles: Love your skin. Check your skin for any unusual spots or moles. Check with your doctor if you notice anything new or unusual. Have them check your skin regularly if you have had skin cancer.

Protecting your eyes.Vision-robbing diseases become more common as you age. Be sure to get your eyes examined regularly -- every 1 to 3 years until age 60, and then every year thereafter. Go more often if you have vision problems or risk factors for eye problems.

Screening for Hepatitis C. The CDC recommends that anyone over the age of 18 get tested for hepatitis C. If you haven't been screened, you should consider having the test.

Depression screening: Depression is a common cause of disability in adults, although it’s often overlooked. It can show up with chronic illness and aging. It’s not a normal part of aging, and you can get treatment. If you're feeling sad, hopeless, or not interested in things you used to enjoy, talk with your doctor. They can see if you're depressed by having you fill out a questionnaire or by asking you a few simple questions.

Immunizations: As you age, you need a few extra vaccines to help you stay healthy, including:

Flu shot: Folks 6 months of age and older should get one every year.

Shingles vaccine: This is recommended if you're 50 or older.

Remember, there's a lot you can do on your own to stay healthy as you age: