3. BLOOD SUGAR Why it’s important: If your blood sugar levels are too high, that means your body doesn’t make enough insulin or can’t use it as well as it should. Over time, if diabetes is

not treated, the extra glucose in your blood can cause serious health problems like heart disease, stroke, kidney failure, vision loss and nerve damage, which can lead to amputations.  If

your blood sugar drops too low, that can also be dangerous, says Ardeshir Hashmi, M.D., section chief of Cleveland Clinic’s Center for Geriatric Medicine. Adults in their late 70s and 80s

tend to be at higher risk because they may not be eating and drinking as much. A drop in blood sugar can cause confusion, dizziness and falls. GOAL: Fasting plasma glucose level of 70-99

with a glucose meter or a continuous glucose monitor. SMART STRATEGIES: Making healthy lifestyle changes is once again your best bet. Research shows a low-carb diet is especially effective

at lowering glucose levels, Hashmi says. Aerobic exercise is also important, he says. Studies show exercise lowers blood sugar levels over time, reduces insulin sensitivity and contributes

to weight loss. Hashmi says exercising regularly is more important than how hard you exercise in each session. If you’ve been diagnosed with diabetes, your doctor will work with you to

create a personalized plan that includes monitoring your blood sugar levels, making dietary changes and possibly taking medication. (For more, see 7 Simple Ways to Lower Your Blood Sugar.)

4. HEARING NUMBER WHY IT’S IMPORTANT: This newly named metric, technically called a four-frequency pure tone average (PTA), measures how loud speech must be for you to hear it. The number

can range from zero to 100 decibels (dB) and can help you better understand your hearing, says Frank Lin, M.D., director of the Cochlear Center for Hearing and Public Health at Johns Hopkins

University and coauthor of AARP’s Hearing Loss for Dummies. The higher the number, the louder sounds need to be for you to hear them. Lin and his colleagues at Johns Hopkins are encouraging

greater use of the number because it offers data on how your hearing changes over time. Traditionally, audiologists diagnose you within more general categories of mild, moderate or severe

hearing loss. “Hearing, for a lot of people, is still this black box,” Lin says. “This is one number that can summarize your audiogram.... You can track your hearing across your lifetime

and act on it.” Hearing loss isn’t just about being able to hear your loved ones or your favorite show on TV. The latest research shows it’s closely linked to other aspects of health,

including cognitive decline, social isolation, depression and lower quality of life. GOAL: Under 20 decibels HOW TO TEST IT: If you’ve had a hearing test from an audiologist, you should have

a hearing number, or PTA, Lin says. And two iPhone apps — offered by Mimi Technologies and Jacoti Hearing Center — provide a free test that will give you your number, Lin says. (Both

companies sell products, but the test and apps are free.) Johns Hopkins researchers are developing a similar app for Android smartphones. AARP members can also take a free at-home hearing

test using their phones; the results of the 10-minute test are reported as being in the normal range, slightly below or substantially below normal. Here are the ranges for different levels

of hearing loss defined by the National Institutes of Health: * Mild: 20-40 * Moderate: 41-60 * Severe: 61-80 * Profound: 81+ SMART STRATEGIES: If your hearing loss is mild or moderate, you

may want to consider one of the over-the-counter hearing aids now available, Lin suggests. Research shows they can be as effective as one you would get from an audiologist, and they tend to

be significantly more affordable. For more severe hearing loss, a prescription device may be needed, or even a cochlear implant. (For more on this, read: How to Shop for an Over-the-Counter

Hearing Aid.) 5. WAIST CIRCUMFERENCE Why it’s important: Belly fat is linked to a higher risk of other serious conditions, including stroke and type 2 diabetes. Measuring your waist is an

easy way to get an idea of how much body fat you have, and that’s a key factor in assessing your health and your risk of chronic illness. Both the World Health Association and the American

Heart Association recommend using waist circumference to screen for risks like heart disease and diabetes. Plus, research shows that belly fat — also called visceral fat — is more harmful

for your health than fat that accumulates in other parts of the body. “There’s a very direct correlation," Hashmi says. "The more fat there is in that area — the [higher] your

waist circumference — the more likelihood there is of you getting a heart attack.” GOAL: Under 35 inches for women, and under 40 inches for men HOW TO TEST IT: To measure your waist

circumference, place a tape measure around your middle, just above your hip bones. Make sure it’s snug but not compressing your skin. Take the measurement just after you breathe out.  SMART

STRATEGIES: Your best bet to shrink your waist is to switch to a healthier diet and consume fewer calories while also moving more. Hashmi says cutting down on carbs can be particularly

helpful. “Carbohydrates in the diet are the ones that go and sort of settle around our tummies,” he says.  When it comes to exercise, abdominal exercises can help strengthen your core, but

they won’t make that belly fat disappear. Instead, experts recommend upping your overall physical activity. Research shows that both aerobic activity and strength training are key to burning

abdominal fat. Aim for 30 to 60 minutes of moderate exercise a day. Even if the scale doesn’t budge, getting more active will still help reduce the amount of dangerous visceral fat in your

gut, studies show. (See: How to Lose Belly Fat After Age 50.)