What do your favorite wool sweater, your retirement savings account and your brain have in common? They're all better off if they don't shrink! But the brains of millions of Americans with slightly elevated blood sugar levels are at risk for just that.

One study making headlines found that even a little extra blood glucose shrivels gray matter. Seems the hippocampus (memories) and amygdala (thinking) areas of the brain grew smaller in women and men whose blood sugar was in the prediabetes range, about 110 mg/dL on a fasting blood sugar test. (And if you progress from prediabetes to diabetes, as most people eventually do, you'll accelerate shrinkage even more.)

But there's a lot you can do to reverse prediabetes and keep your brain cells healthy and your neurons firing.

1. Break out your walking shoes. Exercise stimulates the growth of new neurons and new neuron connections by boosting levels of a protein called BDNF. Even a few 30-minute walks a week protect against cognitive decline, and they're more effective than brain games or spending time with your BFFs. We recommend that you aim for 10,000 steps a day - that'll definitely give prediabetes the heave-ho.

2. Break out your sweats and heart-rate monitor. More-vigorous physical activity (especially using leg and core muscles) increases neural connections and the size of your brain's memory-processing hippocampus. Get your heart rate up to 85 percent of your age-adjusted maximum for 20 minutes, three times a week for top benefits. (A woman's max age-adjusted heart rate is 226 minus her age; and man's is 220 minus his age.)

3. De-stress daily. Chronic worry and anxiety switch on a gene that blocks the creation of new nerve connections. Meditation and exercise are great de-stressers.

4. Get B's, C, D, E - and omega-3s. Loading up on these nutrients found in produce, whole grains, fortified breakfast cereal, low-fat milk and omega-3-rich fish like salmon and trout reduces your risk for brain shrinkage substantially. People who didn't get enough omega-3 had 37 percent more brain loss, in one eye-opening report. You can also take 900 milligrams of omega-3 DHA daily and half a multivitamin twice a day.

5. Skip trans fats. Trans fats reduce brain size. Check all food labels. If you see "partially hydrogenated" fats, especially in baked goods and ready-to-eat frozen and canned meals, put the package back on the shelf.

6. Lower high blood pressure. Anything higher than 117/76 can damage blood vessels that supply brain cells with oxygen and fuel.

7. Stop smoking; avoid secondhand smoke; get your flu shot. Puffing on tobacco chokes the blood supply to your brain. (Visit www.sharecare.com for great tips and support for kicking butts.) Avoiding inflammation in your brain makes you much smarter.

8. Find relief for chronic pain. Inflammation associated with ongoing back pain could thin your gray matter by a whopping 11 percent. Research has shown that chronic back pain can erode a cubic half-inch of brain matter in a single year.

9. Consider supplements that decrease insulin resistance. Cinnamon (2 teaspoons daily), turmeric (17 milligrams as a spice in food), purified omega-7's (210 milligrams daily) and coffee (more than two cups a day if your doc says it's OK for you) all decrease insulin resistance and may improve long-term brain function.

10. Get some sleep. Insomnia is another brain drain. Nix afternoon caffeine, de-stress before turning in, make sure your room is cool and dark. In the morning, snap up the shades and get some early light.

Reversing the  signs of heart disease

Telltale signs of hard living are unmistakable: Think of 26-year-old Lindsay Lohan's once-unlined face. But those of you with less raucous lives also can display physical signs that you're older than your chronological age - and are at risk for heart disease.

A new study identifies a receding hairline at the temples, baldness on the top of the head, horizontal earlobe creases and yellow, fatty deposits around the eyes as markers of aging associated with heart disease. Got any three? Your chance of a heart attack goes up 57 percent.

But you can slash your risk by up to 60 percent and look younger, too, if you adopt some heart-smart habits:

 Eliminate the five food felons: trans fats, most saturated fats, added sugars, sugar syrups and all grains that are not 100 percent whole. Add heart-friendly food (salmon and trout), or take up to 900 milligrams a day of omega-3 DHA.

Exercise and sleep more: Your goal: 10,000 steps a day; strength training two to three times a week; seven to eight hours of nightly shuteye. (Thirty minutes of exercise a day boosts restorative REM sleep by 65 percent.)

 Go by the numbers: Blood pressure (115/75); triglycerides (100 or less); HDL (60 or above); LDL (under 100); blood glucose (85 upon waking up); and BMI (18.5 to 24.9).

Ask your doc about taking two baby aspirins a day: Take with warm water before and after.

After all that, have more fun. People who are more satisfied with their life produce fewer stress hormones, which protects your heart, big-time.

Contact the You Docs at www.realage.com